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    • By elect
      ok, so, we are having problems with our current mirror reflection implementation.
      At the moment we are doing it very simple, so for the i-th frame, we calculate the reflection vectors given the viewPoint and some predefined points on the mirror surface (position and normal).
      Then, using the least squared algorithm, we find the point that has the minimum distance from all these reflections vectors. This is going to be our virtual viewPoint (with the right orientation).
      After that, we render offscreen to a texture by setting the OpenGL camera on the virtual viewPoint.
      And finally we use the rendered texture on the mirror surface.
      So far this has always been fine, but now we are having some more strong constraints on accuracy.
      What are our best options given that:
      - we have a dynamic scene, the mirror and parts of the scene can change continuously from frame to frame
      - we have about 3k points (with normals) per mirror, calculated offline using some cad program (such as Catia)
      - all the mirror are always perfectly spherical (with different radius vertically and horizontally) and they are always convex
      - a scene can have up to 10 mirror
      - it should be fast enough also for vr (Htc Vive) on fastest gpus (only desktops)

      Looking around, some papers talk about calculating some caustic surface derivation offline, but I don't know if this suits my case
      Also, another paper, used some acceleration structures to detect the intersection between the reflection vectors and the scene, and then adjust the corresponding texture coordinate. This looks the most accurate but also very heavy from a computational point of view.

      Other than that, I couldn't find anything updated/exhaustive around, can you help me?
      Thanks in advance
    • By kanageddaamen
      Hello all,
      I am currently working on a game engine for use with my game development that I would like to be as flexible as possible.  As such the exact requirements for how things should work can't be nailed down to a specific implementation and I am looking for, at least now, a default good average case scenario design.
      Here is what I have implemented:
      Deferred rendering using OpenGL Arbitrary number of lights and shadow mapping Each rendered object, as defined by a set of geometry, textures, animation data, and a model matrix is rendered with its own draw call Skeletal animations implemented on the GPU.   Model matrix transformation implemented on the GPU Frustum and octree culling for optimization Here are my questions and concerns:
      Doing the skeletal animation on the GPU, currently, requires doing the skinning for each object multiple times per frame: once for the initial geometry rendering and once for the shadow map rendering for each light for which it is not culled.  This seems very inefficient.  Is there a way to do skeletal animation on the GPU only once across these render calls? Without doing the model matrix transformation on the CPU, I fail to see how I can easily batch objects with the same textures and shaders in a single draw call without passing a ton of matrix data to the GPU (an array of model matrices then an index for each vertex into that array for transformation purposes?) If I do the matrix transformations on the CPU, It seems I can't really do the skinning on the GPU as the pre-transformed vertexes will wreck havoc with the calculations, so this seems not viable unless I am missing something Overall it seems like simplest solution is to just do all of the vertex manipulation on the CPU and pass the pre-transformed data to the GPU, using vertex shaders that do basically nothing.  This doesn't seem the most efficient use of the graphics hardware, but could potentially reduce the number of draw calls needed.

      Really, I am looking for some advice on how to proceed with this, how something like this is typically handled.  Are the multiple draw calls and skinning calculations not a huge deal?  I would LIKE to save as much of the CPU's time per frame so it can be tasked with other things, as to keep CPU resources open to the implementation of the engine.  However, that becomes a moot point if the GPU becomes a bottleneck.
    • By DiligentDev
      I would like to introduce Diligent Engine, a project that I've been recently working on. Diligent Engine is a light-weight cross-platform abstraction layer between the application and the platform-specific graphics API. Its main goal is to take advantages of the next-generation APIs such as Direct3D12 and Vulkan, but at the same time provide support for older platforms via Direct3D11, OpenGL and OpenGLES. Diligent Engine exposes common front-end for all supported platforms and provides interoperability with underlying native API. Shader source code converter allows shaders authored in HLSL to be translated to GLSL and used on all platforms. Diligent Engine supports integration with Unity and is designed to be used as a graphics subsystem in a standalone game engine, Unity native plugin or any other 3D application. It is distributed under Apache 2.0 license and is free to use. Full source code is available for download on GitHub.
      True cross-platform Exact same client code for all supported platforms and rendering backends No #if defined(_WIN32) ... #elif defined(LINUX) ... #elif defined(ANDROID) ... No #if defined(D3D11) ... #elif defined(D3D12) ... #elif defined(OPENGL) ... Exact same HLSL shaders run on all platforms and all backends Modular design Components are clearly separated logically and physically and can be used as needed Only take what you need for your project (do not want to keep samples and tutorials in your codebase? Simply remove Samples submodule. Only need core functionality? Use only Core submodule) No 15000 lines-of-code files Clear object-based interface No global states Key graphics features: Automatic shader resource binding designed to leverage the next-generation rendering APIs Multithreaded command buffer generation 50,000 draw calls at 300 fps with D3D12 backend Descriptor, memory and resource state management Modern c++ features to make code fast and reliable The following platforms and low-level APIs are currently supported:
      Windows Desktop: Direct3D11, Direct3D12, OpenGL Universal Windows: Direct3D11, Direct3D12 Linux: OpenGL Android: OpenGLES MacOS: OpenGL iOS: OpenGLES API Basics
      The engine can perform initialization of the API or attach to already existing D3D11/D3D12 device or OpenGL/GLES context. For instance, the following code shows how the engine can be initialized in D3D12 mode:
      #include "RenderDeviceFactoryD3D12.h" using namespace Diligent; // ...  GetEngineFactoryD3D12Type GetEngineFactoryD3D12 = nullptr; // Load the dll and import GetEngineFactoryD3D12() function LoadGraphicsEngineD3D12(GetEngineFactoryD3D12); auto *pFactoryD3D11 = GetEngineFactoryD3D12(); EngineD3D12Attribs EngD3D12Attribs; EngD3D12Attribs.CPUDescriptorHeapAllocationSize[0] = 1024; EngD3D12Attribs.CPUDescriptorHeapAllocationSize[1] = 32; EngD3D12Attribs.CPUDescriptorHeapAllocationSize[2] = 16; EngD3D12Attribs.CPUDescriptorHeapAllocationSize[3] = 16; EngD3D12Attribs.NumCommandsToFlushCmdList = 64; RefCntAutoPtr<IRenderDevice> pRenderDevice; RefCntAutoPtr<IDeviceContext> pImmediateContext; SwapChainDesc SwapChainDesc; RefCntAutoPtr<ISwapChain> pSwapChain; pFactoryD3D11->CreateDeviceAndContextsD3D12( EngD3D12Attribs, &pRenderDevice, &pImmediateContext, 0 ); pFactoryD3D11->CreateSwapChainD3D12( pRenderDevice, pImmediateContext, SwapChainDesc, hWnd, &pSwapChain ); Creating Resources
      Device resources are created by the render device. The two main resource types are buffers, which represent linear memory, and textures, which use memory layouts optimized for fast filtering. To create a buffer, you need to populate BufferDesc structure and call IRenderDevice::CreateBuffer(). The following code creates a uniform (constant) buffer:
      BufferDesc BuffDesc; BufferDesc.Name = "Uniform buffer"; BuffDesc.BindFlags = BIND_UNIFORM_BUFFER; BuffDesc.Usage = USAGE_DYNAMIC; BuffDesc.uiSizeInBytes = sizeof(ShaderConstants); BuffDesc.CPUAccessFlags = CPU_ACCESS_WRITE; m_pDevice->CreateBuffer( BuffDesc, BufferData(), &m_pConstantBuffer ); Similar, to create a texture, populate TextureDesc structure and call IRenderDevice::CreateTexture() as in the following example:
      TextureDesc TexDesc; TexDesc.Name = "My texture 2D"; TexDesc.Type = TEXTURE_TYPE_2D; TexDesc.Width = 1024; TexDesc.Height = 1024; TexDesc.Format = TEX_FORMAT_RGBA8_UNORM; TexDesc.Usage = USAGE_DEFAULT; TexDesc.BindFlags = BIND_SHADER_RESOURCE | BIND_RENDER_TARGET | BIND_UNORDERED_ACCESS; TexDesc.Name = "Sample 2D Texture"; m_pRenderDevice->CreateTexture( TexDesc, TextureData(), &m_pTestTex ); Initializing Pipeline State
      Diligent Engine follows Direct3D12 style to configure the graphics/compute pipeline. One big Pipelines State Object (PSO) encompasses all required states (all shader stages, input layout description, depth stencil, rasterizer and blend state descriptions etc.)
      Creating Shaders
      To create a shader, populate ShaderCreationAttribs structure. An important member is ShaderCreationAttribs::SourceLanguage. The following are valid values for this member:
      SHADER_SOURCE_LANGUAGE_DEFAULT  - The shader source format matches the underlying graphics API: HLSL for D3D11 or D3D12 mode, and GLSL for OpenGL and OpenGLES modes. SHADER_SOURCE_LANGUAGE_HLSL  - The shader source is in HLSL. For OpenGL and OpenGLES modes, the source code will be converted to GLSL. See shader converter for details. SHADER_SOURCE_LANGUAGE_GLSL  - The shader source is in GLSL. There is currently no GLSL to HLSL converter. To allow grouping of resources based on the frequency of expected change, Diligent Engine introduces classification of shader variables:
      Static variables (SHADER_VARIABLE_TYPE_STATIC) are variables that are expected to be set only once. They may not be changed once a resource is bound to the variable. Such variables are intended to hold global constants such as camera attributes or global light attributes constant buffers. Mutable variables (SHADER_VARIABLE_TYPE_MUTABLE) define resources that are expected to change on a per-material frequency. Examples may include diffuse textures, normal maps etc. Dynamic variables (SHADER_VARIABLE_TYPE_DYNAMIC) are expected to change frequently and randomly. This post describes the resource binding model in Diligent Engine.
      The following is an example of shader initialization:
      ShaderCreationAttribs Attrs; Attrs.Desc.Name = "MyPixelShader"; Attrs.FilePath = "MyShaderFile.fx"; Attrs.SearchDirectories = "shaders;shaders\\inc;"; Attrs.EntryPoint = "MyPixelShader"; Attrs.Desc.ShaderType = SHADER_TYPE_PIXEL; Attrs.SourceLanguage = SHADER_SOURCE_LANGUAGE_HLSL; BasicShaderSourceStreamFactory BasicSSSFactory(Attrs.SearchDirectories); Attrs.pShaderSourceStreamFactory = &BasicSSSFactory; ShaderVariableDesc ShaderVars[] =  {     {"g_StaticTexture", SHADER_VARIABLE_TYPE_STATIC},     {"g_MutableTexture", SHADER_VARIABLE_TYPE_MUTABLE},     {"g_DynamicTexture", SHADER_VARIABLE_TYPE_DYNAMIC} }; Attrs.Desc.VariableDesc = ShaderVars; Attrs.Desc.NumVariables = _countof(ShaderVars); Attrs.Desc.DefaultVariableType = SHADER_VARIABLE_TYPE_STATIC; StaticSamplerDesc StaticSampler; StaticSampler.Desc.MinFilter = FILTER_TYPE_LINEAR; StaticSampler.Desc.MagFilter = FILTER_TYPE_LINEAR; StaticSampler.Desc.MipFilter = FILTER_TYPE_LINEAR; StaticSampler.TextureName = "g_MutableTexture"; Attrs.Desc.NumStaticSamplers = 1; Attrs.Desc.StaticSamplers = &StaticSampler; ShaderMacroHelper Macros; Macros.AddShaderMacro("USE_SHADOWS", 1); Macros.AddShaderMacro("NUM_SHADOW_SAMPLES", 4); Macros.Finalize(); Attrs.Macros = Macros; RefCntAutoPtr<IShader> pShader; m_pDevice->CreateShader( Attrs, &pShader ); Creating the Pipeline State Object
      To create a pipeline state object, define instance of PipelineStateDesc structure. The structure defines the pipeline specifics such as if the pipeline is a compute pipeline, number and format of render targets as well as depth-stencil format:
      // This is a graphics pipeline PSODesc.IsComputePipeline = false; PSODesc.GraphicsPipeline.NumRenderTargets = 1; PSODesc.GraphicsPipeline.RTVFormats[0] = TEX_FORMAT_RGBA8_UNORM_SRGB; PSODesc.GraphicsPipeline.DSVFormat = TEX_FORMAT_D32_FLOAT; The structure also defines depth-stencil, rasterizer, blend state, input layout and other parameters. For instance, rasterizer state can be defined as in the code snippet below:
      // Init rasterizer state RasterizerStateDesc &RasterizerDesc = PSODesc.GraphicsPipeline.RasterizerDesc; RasterizerDesc.FillMode = FILL_MODE_SOLID; RasterizerDesc.CullMode = CULL_MODE_NONE; RasterizerDesc.FrontCounterClockwise = True; RasterizerDesc.ScissorEnable = True; //RSDesc.MultisampleEnable = false; // do not allow msaa (fonts would be degraded) RasterizerDesc.AntialiasedLineEnable = False; When all fields are populated, call IRenderDevice::CreatePipelineState() to create the PSO:
      m_pDev->CreatePipelineState(PSODesc, &m_pPSO); Binding Shader Resources
      Shader resource binding in Diligent Engine is based on grouping variables in 3 different groups (static, mutable and dynamic). Static variables are variables that are expected to be set only once. They may not be changed once a resource is bound to the variable. Such variables are intended to hold global constants such as camera attributes or global light attributes constant buffers. They are bound directly to the shader object:
      PixelShader->GetShaderVariable( "g_tex2DShadowMap" )->Set( pShadowMapSRV ); Mutable and dynamic variables are bound via a new object called Shader Resource Binding (SRB), which is created by the pipeline state:
      m_pPSO->CreateShaderResourceBinding(&m_pSRB); Dynamic and mutable resources are then bound through SRB object:
      m_pSRB->GetVariable(SHADER_TYPE_VERTEX, "tex2DDiffuse")->Set(pDiffuseTexSRV); m_pSRB->GetVariable(SHADER_TYPE_VERTEX, "cbRandomAttribs")->Set(pRandomAttrsCB); The difference between mutable and dynamic resources is that mutable ones can only be set once for every instance of a shader resource binding. Dynamic resources can be set multiple times. It is important to properly set the variable type as this may affect performance. Static variables are generally most efficient, followed by mutable. Dynamic variables are most expensive from performance point of view. This post explains shader resource binding in more details.
      Setting the Pipeline State and Invoking Draw Command
      Before any draw command can be invoked, all required vertex and index buffers as well as the pipeline state should be bound to the device context:
      // Clear render target const float zero[4] = {0, 0, 0, 0}; m_pContext->ClearRenderTarget(nullptr, zero); // Set vertex and index buffers IBuffer *buffer[] = {m_pVertexBuffer}; Uint32 offsets[] = {0}; Uint32 strides[] = {sizeof(MyVertex)}; m_pContext->SetVertexBuffers(0, 1, buffer, strides, offsets, SET_VERTEX_BUFFERS_FLAG_RESET); m_pContext->SetIndexBuffer(m_pIndexBuffer, 0); m_pContext->SetPipelineState(m_pPSO); Also, all shader resources must be committed to the device context:
      m_pContext->CommitShaderResources(m_pSRB, COMMIT_SHADER_RESOURCES_FLAG_TRANSITION_RESOURCES); When all required states and resources are bound, IDeviceContext::Draw() can be used to execute draw command or IDeviceContext::DispatchCompute() can be used to execute compute command. Note that for a draw command, graphics pipeline must be bound, and for dispatch command, compute pipeline must be bound. Draw() takes DrawAttribs structure as an argument. The structure members define all attributes required to perform the command (primitive topology, number of vertices or indices, if draw call is indexed or not, if draw call is instanced or not, if draw call is indirect or not, etc.). For example:
      DrawAttribs attrs; attrs.IsIndexed = true; attrs.IndexType = VT_UINT16; attrs.NumIndices = 36; attrs.Topology = PRIMITIVE_TOPOLOGY_TRIANGLE_LIST; pContext->Draw(attrs); Tutorials and Samples
      The GitHub repository contains a number of tutorials and sample applications that demonstrate the API usage.
      Tutorial 01 - Hello Triangle This tutorial shows how to render a simple triangle using Diligent Engine API.   Tutorial 02 - Cube This tutorial demonstrates how to render an actual 3D object, a cube. It shows how to load shaders from files, create and use vertex, index and uniform buffers.   Tutorial 03 - Texturing This tutorial demonstrates how to apply a texture to a 3D object. It shows how to load a texture from file, create shader resource binding object and how to sample a texture in the shader.   Tutorial 04 - Instancing This tutorial demonstrates how to use instancing to render multiple copies of one object using unique transformation matrix for every copy.   Tutorial 05 - Texture Array This tutorial demonstrates how to combine instancing with texture arrays to use unique texture for every instance.   Tutorial 06 - Multithreading This tutorial shows how to generate command lists in parallel from multiple threads.   Tutorial 07 - Geometry Shader This tutorial shows how to use geometry shader to render smooth wireframe.   Tutorial 08 - Tessellation This tutorial shows how to use hardware tessellation to implement simple adaptive terrain rendering algorithm.   Tutorial_09 - Quads This tutorial shows how to render multiple 2D quads, frequently swithcing textures and blend modes.
      AntTweakBar sample demonstrates how to use AntTweakBar library to create simple user interface.

      Atmospheric scattering sample is a more advanced example. It demonstrates how Diligent Engine can be used to implement various rendering tasks: loading textures from files, using complex shaders, rendering to textures, using compute shaders and unordered access views, etc. 

      The repository includes Asteroids performance benchmark based on this demo developed by Intel. It renders 50,000 unique textured asteroids and lets compare performance of D3D11 and D3D12 implementations. Every asteroid is a combination of one of 1000 unique meshes and one of 10 unique textures. 

      Integration with Unity
      Diligent Engine supports integration with Unity through Unity low-level native plugin interface. The engine relies on Native API Interoperability to attach to the graphics API initialized by Unity. After Diligent Engine device and context are created, they can be used us usual to create resources and issue rendering commands. GhostCubePlugin shows an example how Diligent Engine can be used to render a ghost cube only visible as a reflection in a mirror.

    • By Yxjmir
      I'm trying to load data from a .gltf file into a struct to use to load a .bin file. I don't think there is a problem with how the vertex positions are loaded, but with the indices. This is what I get when drawing with glDrawArrays(GL_LINES, ...):

      Also, using glDrawElements gives a similar result. Since it looks like its drawing triangles using the wrong vertices for each face, I'm assuming it needs an index buffer/element buffer. (I'm not sure why there is a line going through part of it, it doesn't look like it belongs to a side, re-exported it without texture coordinates checked, and its not there)
      I'm using jsoncpp to load the GLTF file, its format is based on JSON. Here is the gltf struct I'm using, and how I parse the file:
      #define GLTF_TARGET_ARRAY_BUFFER (34962) #define GLTF_TARGET_ELEMENT_ARRAY_BUFFER (34963) #define GLTF_COMPONENT_TYPE_BYTE (5120) #define GLTF_COMPONENT_TYPE_UNSIGNED_BYTE (5121) #define GLTF_COMPONENT_TYPE_SHORT (5122) #define GLTF_COMPONENT_TYPE_UNSIGNED_SHORT (5123) #define GLTF_COMPONENT_TYPE_INT (5124) #define GLTF_COMPONENT_TYPE_UNSIGNED_INT (5125) #define GLTF_COMPONENT_TYPE_FLOAT (5126) #define GLTF_COMPONENT_TYPE_DOUBLE (5127) #define GLTF_PARAMETER_TYPE_BYTE (5120) #define GLTF_PARAMETER_TYPE_UNSIGNED_BYTE (5121) #define GLTF_PARAMETER_TYPE_SHORT (5122) #define GLTF_PARAMETER_TYPE_UNSIGNED_SHORT (5123) #define GLTF_PARAMETER_TYPE_INT (5124) #define GLTF_PARAMETER_TYPE_UNSIGNED_INT (5125) #define GLTF_PARAMETER_TYPE_FLOAT (5126) #define GLTF_PARAMETER_TYPE_FLOAT_VEC2 (35664) #define GLTF_PARAMETER_TYPE_FLOAT_VEC3 (35665) #define GLTF_PARAMETER_TYPE_FLOAT_VEC4 (35666) struct GLTF { struct Accessor { USHORT bufferView; USHORT componentType; UINT count; vector<INT> max; vector<INT> min; string type; }; vector<Accessor> m_accessors; struct Asset { string copyright; string generator; string version; }m_asset; struct BufferView { UINT buffer; UINT byteLength; UINT byteOffset; UINT target; }; vector<BufferView> m_bufferViews; struct Buffer { UINT byteLength; string uri; }; vector<Buffer> m_buffers; vector<string> m_Images; struct Material { string name; string alphaMode; Vec4 baseColorFactor; UINT baseColorTexture; UINT normalTexture; float metallicFactor; }; vector<Material> m_materials; struct Meshes { string name; struct Primitive { vector<UINT> attributes_indices; UINT indices; UINT material; }; vector<Primitive> primitives; }; vector<Meshes> m_meshes; struct Nodes { int mesh; string name; Vec3 translation; }; vector<Nodes> m_nodes; struct Scenes { UINT index; string name; vector<UINT> nodes; }; vector<Scenes> m_scenes; vector<UINT> samplers; struct Textures { UINT sampler; UINT source; }; vector<Textures> m_textures; map<UINT, string> attributes_map; map<UINT, string> textures_map; }; GLTF m_gltf; // This is actually in the Mesh class bool Mesh::Load(string sFilename) { string sFileAsString; stringstream sStream; ifstream fin(sFilename); sStream << fin.rdbuf(); fin.close(); sFileAsString = sStream.str(); Json::Reader r; Json::Value root; if (!r.parse(sFileAsString, root)) { string errors = r.getFormatedErrorMessages(); if (errors != "") { // TODO: Log errors return false; } } if (root.isNull()) return false; Json::Value object; Json::Value value; // Load Accessors array, these are referenced by attributes with their index value object = root.get("accessors", Json::Value()); // store object with key "accessors", if not found it will default to Json::Value() if (!object.isNull()) { for (Json::ValueIterator it = object.begin(); it != object.end(); it++) { GLTF::Accessor accessor; value = (*it).get("bufferView", Json::Value()); if (!value.isNull()) accessor.bufferView = value.asUINT(); else return false; value = (*it).get("componentType", Json::Value()); if (!value.isNull()) accessor.componentType = value.asUINT(); else return false; value = (*it).get("count", Json::Value()); if (!value.isNull()) accessor.count = value.asUINT(); else return false; value = (*it).get("type", Json::Value()); if (!value.isNull()) accessor.type = value.asString(); else return false; m_gltf.accessors.push_back(accessor); } } else return false; object = root.get("bufferViews", Json::Value()); if(!object.isNull()) { for (Json::ValueIterator it = object.begin(); it != object.end(); it++) { GLTF::BufferView bufferView; value = (*it).get("buffer", Json::Value()); if(!value.isNull()) bufferView.buffer = value.asUInt(); else return false; value = (*it).get("byteLength", Json::Value()); if(!value.isNull()) bufferView.byteLength = value.asUInt(); else return false; value = (*it).get("byteOffset", Json::Value()); if(!value.isNull()) bufferView.byteOffset = value.asUInt(); else return false; value = (*it).get("target", Json::Value()); if(!value.isNull()) bufferView.target = value.asUInt(); else return false; m_gltf.m_bufferViews.push_back(bufferView); } } else return false; object = root.get("buffers", Json::Value()); if(!object.isNull()) { for (Json::ValueIterator it = object.begin(); it != object.end(); it++) { GLTF::Buffer buffer; value = (*it).get("byteLength", Json::Value()); if(!value.isNull()) buffer.byteLength = value.asUInt(); else return false; // Store the filename of the .bin file value = (*it).get("uri", Json::Value()); if(!value.isNull()) buffer.uri = value.asString(); else return false; } } else return false; object = root.get("meshes", Json::Value()); if(!object.isNull()) { for(Json::ValueIterator it = object.begin(); it != object.end(); it++) { GLTF::Meshes mesh; value = (*it).get("primitives", Json::Value()); for(Json::ValueIterator value_it = value.begin(); value_it != value.end(); value_it++) { GLTF::Meshes::Primitive primitive; Json::Value attributes; attributes = (*value_it).get("attributes", Json::Value()); vector<string> memberNames = attributes.getMemberNames(); for(size_t i = 0; i < memberNames.size(); i++) { Json::Value member; member = attributes.get(memeberNames[i], Json::Value()); if(!member.isNull()) { primitive.attributes_indices.push_back(member.asUInt()); m_gltf.attributes_map[member.asUInt()] = memberNames[i]; // Each of these referes to an accessor by indice, so each indice should be unique, and they are when loading a cube } else return false; } // Indice of the accessor used for indices Json::Value indices; indices = (*value_it).get("indices", Json::Value()); primitive.indices = indices.asUInt(); mesh.primitives.push_back(primitive); } m_gltf.m_meshes.push_back(mesh); } } vector<float> vertexData; vector<USHORT> indiceData; int vertexBufferSizeTotal = 0; int elementBufferSizeTotal = 0; GLTF::Meshes mesh = m_gltf.m_meshes[0]; vector<GLTF::Meshes::Primitive> primitives = mesh.primitives; // trying to make the code easier to read for (size_t p = 0; p < primitive.size(); p++) { vector<UINT> attributes = primitives[p].attributes_indices; for(size_t a = 0; a < attributes.size(); a++) { GLTF::Accessor accessor = m_gltf.m_accessors[attributes[a]]; GLTF::BufferView bufferView = m_gltf.m_bufferViews[accessor.bufferView]; UINT target = bufferView.target; if(target == GLTF_TARGET_ARRAY_BUFFER) vertexBufferSizeTotal += bufferView.byteLength; } UINT indice = primitives[p].indices; GLTF::BufferView bufferView = m_gltf.m_bufferViews[indice]; UINT target = bufferView.target; if(target == GLTF_TARGET_ELEMENT_ARRAY_BUFFER) elementBufferSizeTotal += bufferView.byteLength; } // These have already been generated glBindVertexArray(g_pGame->m_VAO); glBindBuffer(GL_ARRAY_BUFFER, g_pGame->m_VBO); glBufferData(GL_ARRAY_BUFFER, vertexBufferSizeTotal, nullptr, GL_STATIC_DRAW); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_pGame->m_EBO); glBufferData(GL_ELEMENT_ARRAY_BUFFER, elementBufferSizeTotal, nullptr, GL_STATIC_DRAW); int offset = 0; int offset_indice = 0; for (size_t p = 0; p < primitive.size(); p++) { vector<UINT> attributes = primitives[p].attributes_indices; int pos = sFilename.find_last_of('\\') + 1; string sFolder = sFilename.substr(0, pos); for (size_t a = 0; a < attributes.size(); a++) { LoadBufferView(sFolder, attributes[a], data, offset); } UINT indice = primitives[p].indices; GLTF::BufferView bufferView_indice = m_gltf.m_bufferViews[indice]; UINT target_indice = bufferView_indice.target; bool result = LoadBufferView(sFolder, indice, data, offset_indice); if(!result) return false; } return true; } bool Mesh::LoadBufferView(string sFolder, UINT a, vector<float> &vertexData, vector<float> &indiceData, int &offset_indice) { ifstream fin; GLTF::Accessor accessor = m_gltf.m_accessors[a]; GLTF::BufferView bufferView = m_gltf.m_bufferViews[accessor.bufferView]; GLTF::Buffer buffer = m_gltf.m_buffers[bufferView.buffer]; const size_t count = accessor.count; UINT target = bufferView.target; int elementSize; int componentSize; int numComponents; string sFilename_bin = sFolder + buffer.uri; fin.open(sFilename_bin, ios::binary); if (fin.fail()) { return false; } fin.seekg(bufferView.byteOffset, ios::beg); switch (accessor.componentType) { case GLTF_COMPONENT_TYPE_BYTE: componentSize = sizeof(GLbyte); break; case GLTF_COMPONENT_TYPE_UNSIGNED_BYTE: componentSize = sizeof(GLubyte); break; case GLTF_COMPONENT_TYPE_SHORT: componentSize = sizeof(GLshort); break; case GLTF_COMPONENT_TYPE_UNSIGNED_SHORT: componentSize = sizeof(GLushort); break; case GLTF_COMPONENT_TYPE_INT: componentSize = sizeof(GLint); break; case GLTF_COMPONENT_TYPE_UNSIGNED_INT: componentSize = sizeof(GLuint); break; case GLTF_COMPONENT_TYPE_FLOAT: componentSize = sizeof(GLfloat); break; case GLTF_COMPONENT_TYPE_DOUBLE: componentSize = sizeof(GLfloat); break; default: componentSize = 0; break; } if (accessor.type == "SCALAR") numComponents = 1; else if (accessor.type == "VEC2") numComponents = 2; else if (accessor.type == "VEC3") numComponents = 3; else if (accessor.type == "VEC4") numComponents = 4; else if (accessor.type == "MAT2") numComponents = 4; else if (accessor.type == "MAT3") numComponents = 9; else if (accessor.type == "MAT4") numComponents = 16; else return false; vector<float> fSubdata; // I'm pretty sure this is one of the problems, or related to it. If I use vector<USHORT> only half of the vector if filled, if I use GLubyte, the entire vector is filled, but the data might not be right vector<GLubyte> nSubdata; elementSize = (componentSize) * (numComponents); // Only fill the vector I'm using if (accessor.type == "SCALAR") { nSubdata.resize(count * numComponents); fin.read(reinterpret_cast<char*>(&nSubdata[0]), count/* * elementSize*/); // I commented this out since I'm not sure which size the .bin is storing the indice values, and I kept getting runtime errors, no matter what type I used for nSubdata } else { fSubdata.resize(count * numComponents); fin.read(reinterpret_cast<char*>(&fSubdata[0]), count * elementSize); } switch (target) { case GLTF_TARGET_ARRAY_BUFFER: { vertexData.insert(vertexData.end(), fSubdata.begin(), fSubdata.end()); glBindBuffer(GL_ARRAY_BUFFER, g_pGame->m_VBO); glBufferSubData(GL_ARRAY_BUFFER, offset, fSubdata.size() * componentSize, &fSubdata[0]); int attribute_index = 0; // I'm only loading vertex positions, the only attribute stored in the files for now glEnableVertexAttribArray(attribute_index); glVertexAttribPointer(0, numComponents, GL_FLOAT, GL_FALSE, componentSize * numComponents, (void*)(offset)); }break; case GLTF_TARGET_ELEMENT_ARRAY_BUFFER: { indiceData.insert(indiceData.end(), nSubdata.begin(), nSubdata.end()); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_pGame->m_EBO); // This is another area where I'm not sure of the correct values, but if componentSize is the correct size for the type being used it should be correct glBufferSubData is expecting the size in bytes, right? glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, offset, nSubdata.size() * componentSize, &nSubdata[0]); }break; default: return false; } if (accessor.type == "SCALAR") offset += nSubdata.size() * componentSize; else offset += fSubdata.size() * componentSize; fin.close(); return true; } these are the draw calls, I only use one at a time, but neither is currently display properly, g_pGame->m_indices is the same as indiceData vector, and vertexCount contains the correct vertex count, but I forgot to copy the lines of code containing where I set them, which is at the end of Mesh::Load(), I double checked the values to make sure.
      glDrawElements(GL_LINES, g_pGame->m_indices.size(), GL_UNSIGNED_BYTE, (void*)0); // Only shows with GL_UNSIGNED_BYTE
      glDrawArrays(GL_LINES, 0, g_pGame->m_vertexCount);
      So, I'm asking what type should I use for the indices? it doesn't seem to be unsigned short, which is what I selected with the Khronos Group Exporter for blender. Also, am I reading part or all of the .bin file wrong?
    • By ritzmax72
      That means how do I use base DirectX or OpenGL api's to make a physics based destruction simulation? 
      Will it be just smart rendering or something else is required?
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OpenGL Can't get skeletal animation to work [SOLVED :-) ]

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I have been trying to get this to work for the past few weeks but to no avail. Apparently I must still be missing something.

Some background information first:


I use 2 executables, the first one uses Assimp to import mesh, skeleton and animation data. I save everything in 3 separate binary files.

The second program is a modified Rastertek Tutorial, one of the initial ones with basic lighting, to which I'm trying to add vertex skinning.

Loading a static mesh works perfectly. I've also successfully modified the vertex input signature to include the indices and blendweights.


My binary format is extremely simple and, dare I say, naive. The Assimp structures usually consist of a mNumSomething which I save with a simple ofstream e.g. ofs.write( (char *) &numvtxindices, 4); followed with a for loop that iterates the items and writes them too.

It's very easy to read this data back by getting the number of items, then reading them in a loop and cast to the original or a similar same sized structure.


I also flattened the skeletal node hierarchy to a simple array of parent ids as in this tutorial:



Creating a current pose should really be as simple as iterating this array and for each node:

uint parentid = mHierarchy;

mGlobalPoses = mLocalPoses * mGlobalPoses[parentid];


then upload mInvBindMatrices * mGlobalPoses to the shader. Or so I thought, because nothing works.

I just get Spaghetti Bolognaise whatever combination I try, invert Assimps offset matrix or not, transpose or not etc.


Now it might sound like I'm just trying random hacks but in reality I think I do know that for DirectXmath's row-major matrices the above is the right combination, with Assimp's mOffset aiMatrices transposed to XMMATRIX, and aiQuats order (w,x,y,z) swizzled to XMVECTOR's (x,y,z,w)

It doesn't help that most examples are in OpenGL too.


I haven't interpolated anything yet. It's a single pose for which i created a temporary class, adequately named testpose (lol), and probably used a lot of bad coding practices just to keep it simple. I made every member variable public for easy access when sending the matrix palette, 

din't create many separate methods etc. Moreover I have still kept skeleton & anim data together. I'm aware once it works it'll need to be split.


OK, now that this is out of the way let's post the most relevant code.


Let's start with the polygon layout

polygonLayout[0].SemanticName = "POSITION";
polygonLayout[0].SemanticIndex = 0;
polygonLayout[0].Format = DXGI_FORMAT_R32G32B32_FLOAT;
polygonLayout[0].InputSlot = 0;
polygonLayout[0].AlignedByteOffset = 0;
polygonLayout[0].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
polygonLayout[0].InstanceDataStepRate = 0;
polygonLayout[1].SemanticName = "TEXCOORD";
polygonLayout[1].SemanticIndex = 0;
polygonLayout[1].Format = DXGI_FORMAT_R32G32_FLOAT;
polygonLayout[1].InputSlot = 0;
polygonLayout[1].AlignedByteOffset = D3D11_APPEND_ALIGNED_ELEMENT;
polygonLayout[1].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
polygonLayout[1].InstanceDataStepRate = 0;
polygonLayout[2].SemanticName = "NORMAL";
polygonLayout[2].SemanticIndex = 0;
polygonLayout[2].Format = DXGI_FORMAT_R32G32B32_FLOAT;
polygonLayout[2].InputSlot = 0;
polygonLayout[2].AlignedByteOffset = D3D11_APPEND_ALIGNED_ELEMENT;
polygonLayout[2].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
polygonLayout[2].InstanceDataStepRate = 0;
polygonLayout[3].SemanticName = "BLENDINDICES";
polygonLayout[3].SemanticIndex = 0;
polygonLayout[3].Format = DXGI_FORMAT_R32G32B32A32_UINT;
polygonLayout[3].InputSlot = 0;
polygonLayout[3].AlignedByteOffset = D3D11_APPEND_ALIGNED_ELEMENT;
polygonLayout[3].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
polygonLayout[3].InstanceDataStepRate = 0;
polygonLayout[4].SemanticName = "BLENDWEIGHT";
polygonLayout[4].SemanticIndex = 0;
polygonLayout[4].Format = DXGI_FORMAT_R32G32B32A32_FLOAT;
polygonLayout[4].InputSlot = 0;
polygonLayout[4].AlignedByteOffset = D3D11_APPEND_ALIGNED_ELEMENT;
polygonLayout[4].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
polygonLayout[4].InstanceDataStepRate = 0;
// Get a count of the elements in the layout.
    numElements = sizeof(polygonLayout) / sizeof(polygonLayout[0]);
// Create the vertex input layout.
result = device->CreateInputLayout(polygonLayout, numElements, vertexShaderBuffer->GetBufferPointer(), vertexShaderBuffer->GetBufferSize(), 
return false;

The vertex shader

// Filename: light.vs
#define MAXJOINTS 60
cbuffer MatrixBuffer
matrix worldMatrix;
matrix viewMatrix;
matrix projectionMatrix;
matrix joints[MAXJOINTS];
cbuffer CameraBuffer
    float3 cameraPosition;
float padding;
struct VertexInputType
    float4 position : POSITION;
    float2 tex : TEXCOORD0;
float3 normal : NORMAL;
uint4 boneidx : BLENDINDICES;
float4 bonewgt : BLENDWEIGHT;
struct PixelInputType
    float4 position : SV_POSITION;
    float2 tex : TEXCOORD0;
float3 normal : NORMAL;
float3 viewDirection : TEXCOORD1;
// Vertex Shader
PixelInputType LightVertexShader(VertexInputType input)
    PixelInputType output;
float4 worldPosition;
float4 skinnedpos = float4(0.0f,0.0f,0.0f,1.0f);
// Change the position vector to be 4 units for proper matrix calculations.
    input.position.w = 1.0f;
//transform according to joint matrix palette
skinnedpos += input.bonewgt.x * mul(input.position, joints[input.boneidx.x]);
skinnedpos += input.bonewgt.y * mul(input.position, joints[input.boneidx.y]);
skinnedpos += input.bonewgt.z * mul(input.position, joints[input.boneidx.z]);
    skinnedpos += input.bonewgt.w * mul(input.position, joints[input.boneidx.w]);
skinnedpos.w = 1.0f;
// Calculate the position of the vertex against the world, view, and projection matrices.
    output.position = mul(skinnedpos, worldMatrix);
    output.position = mul(output.position, viewMatrix);
    output.position = mul(output.position, projectionMatrix);
//todo: transform normals too but since it doesn't work they can wait
// Store the texture coordinates for the pixel shader.
output.tex = input.tex;
// Calculate the normal vector against the world matrix only.
    output.normal = mul(input.normal, (float3x3)worldMatrix);
    // Normalize the normal vector.
    output.normal = normalize(output.normal);
// Calculate the position of the vertex in the world.
    worldPosition = mul(input.position, worldMatrix);
    // Determine the viewing direction based on the position of the camera and the position of the vertex in the world.
    output.viewDirection = cameraPosition.xyz - worldPosition.xyz;
    // Normalize the viewing direction vector.
    output.viewDirection = normalize(output.viewDirection);
    return output;

The code that sends the cBuffers

bool LightShaderClass::SetShaderParameters(ID3D11DeviceContext* deviceContext,XMMATRIX * globalPoses, unsigned int numJoints, const XMMATRIX& worldMatrix, const XMMATRIX& viewMatrix,
  const XMMATRIX& projectionMatrix, ID3D11ShaderResourceView* texture, const XMFLOAT3& lightDirection, 
  const XMFLOAT4& ambientColor, const XMFLOAT4& diffuseColor, const XMFLOAT3& cameraPosition, const XMFLOAT4& specularColor, float specularPower )
HRESULT result;
    D3D11_MAPPED_SUBRESOURCE mappedResource;
unsigned int bufferNumber;
MatrixBufferType* dataPtr;
LightBufferType* dataPtr2;
CameraBufferType* dataPtr3;
XMMATRIX worldMatrixCopy,viewMatrixCopy,projectionMatrixCopy;
// Transpose the matrices to prepare them for the shader.
worldMatrixCopy = XMMatrixTranspose( worldMatrix );
viewMatrixCopy = XMMatrixTranspose( viewMatrix );
projectionMatrixCopy = XMMatrixTranspose( projectionMatrix );
// Lock the constant buffer so it can be written to.
result = deviceContext->Map(m_matrixBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mappedResource);
return false;
// Get a pointer to the data in the constant buffer.
dataPtr = (MatrixBufferType*)mappedResource.pData;
// Copy the matrices into the constant buffer.
dataPtr->world = worldMatrixCopy;
dataPtr->view = viewMatrixCopy;
dataPtr->projection = projectionMatrixCopy;
for(unsigned char i = 0; i < numJoints; i++)
dataPtr->joints[i] = XMMatrixTranspose( globalPoses[i]);
//dataPtr->joints[i] = globalPoses[i];
//dataPtr->joints[i] = XMMatrixIdentity();
// Unlock the constant buffer.
    deviceContext->Unmap(m_matrixBuffer, 0);
// Set the position of the constant buffer in the vertex shader.
bufferNumber = 0;
// Now set the constant buffer in the vertex shader with the updated values.
    deviceContext->VSSetConstantBuffers(bufferNumber, 1, &m_matrixBuffer);
// Lock the camera constant buffer so it can be written to.
result = deviceContext->Map(m_cameraBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mappedResource);
return false;
// Get a pointer to the data in the constant buffer.
dataPtr3 = (CameraBufferType*)mappedResource.pData;
// Copy the camera position into the constant buffer.
dataPtr3->cameraPosition = cameraPosition;
dataPtr3->padding = 0.0f;
// Unlock the camera constant buffer.
deviceContext->Unmap(m_cameraBuffer, 0);
// Set the position of the camera constant buffer in the vertex shader.
bufferNumber = 1;
// Now set the camera constant buffer in the vertex shader with the updated values.
deviceContext->VSSetConstantBuffers(bufferNumber, 1, &m_cameraBuffer);
// Set shader texture resource in the pixel shader.
deviceContext->PSSetShaderResources(0, 1, &texture);
// Lock the light constant buffer so it can be written to.
result = deviceContext->Map(m_lightBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mappedResource);
return false;
// Get a pointer to the data in the light constant buffer.
dataPtr2 = (LightBufferType*)mappedResource.pData;
// Copy the lighting variables into the light constant buffer.
dataPtr2->ambientColor = ambientColor;
dataPtr2->diffuseColor = diffuseColor;
dataPtr2->lightDirection = lightDirection;
dataPtr2->specularColor = specularColor;
dataPtr2->specularPower = specularPower;
// Unlock the light constant buffer.
deviceContext->Unmap(m_lightBuffer, 0);
// Set the position of the light constant buffer in the pixel shader.
bufferNumber = 0;
// Finally set the light constant buffer in the pixel shader with the updated values.
deviceContext->PSSetConstantBuffers(bufferNumber, 1, &m_lightBuffer);
return true;
void LightShaderClass::RenderShader(ID3D11DeviceContext* deviceContext, int indexCount)
// Set the vertex input layout.
    // Set the vertex and pixel shaders that will be used to render this triangle.
    deviceContext->VSSetShader(m_vertexShader, NULL, 0);
    deviceContext->PSSetShader(m_pixelShader, NULL, 0);
// Set the sampler state in the pixel shader.
deviceContext->PSSetSamplers(0, 1, &m_sampleState);
// Render the triangle.
deviceContext->DrawIndexed(indexCount, 0, 0);

The vertex declaration

struct VertexType
XMFLOAT3 position;
   XMFLOAT2 texture;
XMFLOAT3 normal;
unsigned int blendindices[4];
 float blendweights[4];

My "testpose" header file

* This class is only used for testing a frame of an animation e.g. 1 pose at a given keyframe
#pragma once
#include <DirectXMath.h>
#include <iostream>
#include <fstream>
using namespace DirectX;
using namespace std;
class testpose
struct Channel 
unsigned int mNumChannels;
Channel *mChannels;
bool Init(void);
unsigned int mNumJoints;
unsigned int *mHierarchy;
XMMATRIX *mInvbindpose;
XMMATRIX *mLocalPoses;
XMMATRIX *mGlobalPoses;

My testpose's code //testpose.cpp

#include "testpose.h"
mNumChannels = 0;
mChannels = nullptr;
mNumJoints = 0;
mHierarchy = nullptr;
mInvbindpose = nullptr;
mLocalPoses = nullptr;
mGlobalPoses = nullptr;
if(mChannels != nullptr)
delete[] mChannels;
mChannels = nullptr;
if(mHierarchy != nullptr)
delete[] mHierarchy;
mHierarchy = nullptr;
if(mInvbindpose != nullptr)
mInvbindpose = nullptr;
if(mLocalPoses != nullptr)
mLocalPoses = nullptr;
if(mGlobalPoses != nullptr)
mGlobalPoses = nullptr;
bool testpose::Init(void)
ifstream ifs("../data/anim1frame.bin", std::ifstream::in | ios::binary);
return false;
//------------------Read in a frame of animation--------------------------------------------
ifs.read( (char*) &mNumChannels,4);
if(mNumChannels == 0)
return false;
mChannels = new Channel[mNumChannels];
for(unsigned int i = 0; i < mNumChannels; i++)
ifs.read( (char*) &mChannels[i].S, 3 * 4);
ifs.read( (char*) &mChannels[i].R, 4 * 4);
ifs.read( (char*) &mChannels[i].T, 3 * 4);
//---------------read in bone data such as hierarchy and inverse bind transform-----------------------------------------------
ifs.open("../data/skeleton.bin",  std::ifstream::in | ios::binary);
return false;
//determine number of joints
ifs.read( (char*) &mNumJoints,4);
if(mNumJoints == 0)
return false;
mHierarchy = new unsigned int[mNumJoints];
for(unsigned int i = 0; i < mNumJoints; i++)
ifs.read( (char*) &mHierarchy[i],4);
mInvbindpose = (XMMATRIX*) _aligned_malloc(sizeof(XMMATRIX) * mNumJoints,16);
for(unsigned int i = 0; i < mNumJoints; i++)
ifs.read( (char*) &mInvbindpose[i],16 * 4); //4x4 matrix of 4 byte floats
mInvbindpose[i] = XMMatrixTranspose(mInvbindpose[i]);
//-------------------------------------convert the animation from vectors & quaternions to actual SIMD-friendly matrices--------------
mLocalPoses = (XMMATRIX *) _aligned_malloc( sizeof(XMMATRIX) * mNumChannels, 16);
for(unsigned int i = 0; i < mNumChannels; i++)
//aiQuaternions that were saved are stored as <w,x,y,z> but XMVECTORS use the <x,y,z,w> convention
float x,y,z,w;
w = mChannels[i].R.x;
x = mChannels[i].R.y;
y = mChannels[i].R.z;
z = mChannels[i].R.w;
XMVECTOR S = XMLoadFloat3(&mChannels[i].S);
XMVECTOR R = XMVectorSet(x,y,z,w);
XMVECTOR T = XMLoadFloat3(&mChannels[i].T);
XMMATRIX Smat = XMMatrixScalingFromVector(S);
XMMATRIX Rmat = XMMatrixRotationQuaternion(R);
XMMATRIX Tmat = XMMatrixTranslationFromVector(T);
XMMATRIX SRTmat = Smat * Rmat * Tmat;
//XMMATRIX SRTmat =Tmat * Rmat * Smat;
//SRTmat = XMMatrixTranspose(SRTmat);
mLocalPoses[i] = SRTmat;
//XMMatrixDecompose(&Stmp,&Rtmp,&Ttmp,SRTmat); //just tried to debug this to see whether data seemed valid, it seemed like it was.
//--------------------------------------create global poses from the hierarchy ---------------------------------------------------------
mGlobalPoses = (XMMATRIX *) _aligned_malloc( sizeof(XMMATRIX) * mNumChannels, 16);
for(unsigned int i = 0; i < mNumChannels; i++)
if(mHierarchy[i] == -1)
mGlobalPoses[i] = mLocalPoses[i];
unsigned int parentid = mHierarchy[i];
mGlobalPoses[i] = mLocalPoses[i] * mGlobalPoses[parentid];
//mGlobalPoses[i] = mGlobalPoses[parentid] * mLocalPoses[i]; //I've tried permutations of this
//-------------------------------------------------generate final Matrix Palette for the vertex shader ---------------------------------------------
for(unsigned int i = 0; i < mNumChannels; i++)
//mGlobalPoses[i] = mGlobalPoses[i] * mInvbindpose[i]; //I've tried permutations of this too and combinations with the above ones
mGlobalPoses[i] = mInvbindpose[i] * mGlobalPoses[i];
return true;

What model I am using (it's a test model from Assimp itself)

scene = importer.ReadFile( "../../../../../SDKs/assimp-3.1.1-win-binaries/test/models/X/BCN_Epileptic.x", 
        aiProcess_CalcTangentSpace       | 
        aiProcess_Triangulate            |
        aiProcess_JoinIdenticalVertices  | 
aiProcessPreset_TargetRealtime_Quality | 
aiProcess_OptimizeGraph | 
aiProcess_OptimizeMeshes |
&~aiProcess_FindInvalidData | //recommended on a tutorial
  // If the import failed, report it
  if( scene == nullptr)
   cout << "import failed" << endl;
    return -1;

How I saved 1 frame of animations, no interpolation yet

 //---------------------------------------------------temp 1 frame of animation--------------------------------------------------
  cout << "saving one frame of animation" << endl;
  ofstream ostmp("anim1frame.bin", std::ofstream::out | ios::binary);
  ostmp.write( (char*) &scene->mAnimations[0]->mNumChannels,4);
  for(unsigned int chanidx = 0; chanidx < scene->mAnimations[0]->mNumChannels; chanidx++)
 aiVector3D S,T;
 aiQuaternion R;
 unsigned int rotidx = 0;
 scene->mAnimations[0]->mChannels[chanidx]->mNumRotationKeys > 1 ? rotidx = 45 : rotidx = 0; //not all channels have an array of rotations
 S = scene->mAnimations[0]->mChannels[chanidx]->mScalingKeys[0].mValue; //none of them have more than one
 R = scene->mAnimations[0]->mChannels[chanidx]->mRotationKeys[rotidx].mValue; //well 1 or 100 depending on the channel, choose 45 for no apparent reason (somewhere mid-anim)
 T = scene->mAnimations[0]->mChannels[chanidx]->mPositionKeys[0].mValue; //same as scalings
 ostmp.write( (char*) &S,3*4);
 ostmp.write( (char*) &R,4*4);
 ostmp.write( (char*) &T,3*4);
  cout << endl;

How my skeleton was saved

//------------------------------ save skeleton data-----------------------------------------------------------------
 cout << "saving skeleton" << endl;
  ofstream ofskel ("skeleton.bin", std::ofstream::out | ios::binary);
  unsigned int numnodestosave = flattenedNodes.size();
  ofskel.write( (char*) &numnodestosave,4);
  for (unsigned int i = 0; i < numnodestosave; i++)
 ofskel.write( (char*) &flattenedNodes[i].id, 4); // 4 byte ids
  for (unsigned int i = 0; i < numnodestosave; i++)
  ofskel.write( (char*) &flattenedNodes[i].invbindpose, 4 * 4 * 4); // 4 bytes per float, 4x4 matrix

For completeness, I added a Renderdoc screen cap that shows indices and weights seem OK.







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You can help others help you (by doing something other than staring at the code you've already stared at - TL;DR) by determining (by following the data) at a minimum which section of code causes the problem. That is, look at the run-time values of variables at various places in your code to determine if they're correct. If they are correct, the problem is somewhere later in the "loop." If they're incorrect, the problem is occurring before that code. E.g., is the data imported correctly? That is, have you examined the actual data (run-time) after import?


As a suggestion, your goal should be to be able to post: "At [some-specified-point-in-my-code], I've verified the input data is correct; the matrix values are correct; there are no errors indicated in any function calls up to the point; and the debug runtime reports no problems. But, after the following 4 lines of code are executed, the results are incorrect as follows: ..."


Also, it appears you've jumped from a static cube to a much more complex hierarchical mesh. If you create a very simple hierarchy to begin with, and your 1000 lines of code don't work, finding what portion of the code is causing the problem will be much simpler.


it might sound like I'm just trying random hacks


Actually, you are just hacking, which sometimes works. But it's much better to understand what you should be doing, and verify that the code actually does what you think it should, rather than "discovering" what works by guessing.


EDIT: There's no problem with not understanding why a line of code doesn't do what you think it should. We've all been there. wink.png Just suggesting you be the one to find that line of code!




I think [emphasis mine - buckeye] I do know that for DirectXmath's row-major matrices the above is the right combination


Row-major or not, a matrix with incorrect values will probably result in something you don't want. It's much better to verify that the actual values at run-time are correct, or at least, what you think is correct. Have you done that?

Edited by Buckeye

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Thanks for answering.

I want to clarify one thing, I'm not a noob who just made his first cube just because I said I used an early rastertek tutorial.

In fact I did them all including refraction & reflection,shadows, their whole terrain tuts etc.

If I used an early tut it's because I needed a framework that was easy enough to add to and it would have seemed a weird choice to choose one where there's already a skybox, reflection, simple collisons etc...


As far as looking at variables at exact places etc (aka debugging?) I've done that where I could, I think I saw meaningful matrices (I mean a matrix with values like 1546789,98654544,23455,-454545435435,545343 etc would show as weird. I did see meaningful values. I did use XMMatrixdecompose() to see whether the individual S,R,T values made at least a little sense but in the end of the day I think I can't tell whether values that do look ok are the ones to be expected in vertex skinning because it's such a long chain of events and I can't know the actual end values. I'm not sure if this makes sense.

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I did see meaningful values. I did use XMMatrixdecompose() to see whether the individual S,R,T values made at least a little sense but in the end of the day I think I can't tell whether values that do look ok are the ones to be expected in vertex skinning because it's such a long chain of events and I can't know the actual end values. I'm not sure if this makes sense.


Oh, yeah, it makes sense. biggrin.png  Anyone who's gotten into skinned mesh animation has been there. Also, I wasn't trying to imply you were a noob at programming. Just seemed like you weren't sure where to look, and link was intended to give some idea where to start. Seriously, particularly for finding problems with skinned mesh animation, if "meaningful" doesn't mean "correct", that isn't enough.


A response you should expect to hear: you've got 1000 lines of untested code, pieced together from what sounds like several sources, you have a custom binary format file, you coded an import routine, and imported relatively complex data that may or may not be loaded correctly, and expect it all to fire up the first time? Really?


That's out of the way, so get yourself down to serious business (if you really want it all to work). I still suggest you "follow the data." If you don't know what good data looks like, then give yourself a chance. Go into Blender (or whatever you're modeling program is) and create the simplest skinned mesh you can get away with - maybe just 2 or 3 bones, a couple of boxes to skin, positioned at easily recognized values such as (0,0,0), (0,1,0), etc, all bones and boxes aligned vertically, each vertex weighted to just 1 bone - something like that. Create an animation of 1 or 2 frames with no rotations or translations. Vertex data is easy to recognize as correct, the animation SRT's are trivial, you have simple matrices to look at, etc.


Start with loading the data, and make sure it's correct - not "meaningful" - correct. That includes vertices, matrices, animation values, etc. There's absolutely no sense in debugging code which may be FUBAR, if the input data is FUBAR.


Follow the data from there. E.g.,  you posted "Creating a current pose should really be as simple as ..." Go look at it!

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Go into Blender (or whatever you're modeling program is) and create the simplest skinned mesh you can get away with - maybe just 2 or 3 bones, a couple of boxes to skin, positioned at easily recognized values such as (0,0,0), (0,1,0), etc, all bones and boxes aligned vertically, each vertex weighted to just 1 bone

This is something I was considering next, although I was hoping to avoid it as Blender has a steep learning curve of its own.

I think I will first try another test model with fewer bones such as the wuson.


Start with loading the data, and make sure it's correct - not "meaningful" - correct.

I think this is where I might use a small recap as I'm starting to have doubts.

Are localposes & offset matrices, and applying those 2 equations above to get global poses really all there is to it or did I miss something?

I've read at several tutorials or forum posts that the transform in aiNodes is only used when there is no animation and that you can ignore them for animations because the animation data replaces, not complements, those.

If I can be 100% confident about this then it's obviously my data trail that's wrong, probably in my importer or something.

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OK guys, I found a huge flaw in the way I saved animations.

That model was composed of 3 meshes. I only used mesh 0, saved offset matrices for it but while saving animations I just saved all channels, even those which affected nodes for which I didn't save offset matrices (those nodes that probably affect mesh 1 and 2)


I obviously have to match anim node with ainodes the same way I did for offset matrices. I must've been drunk when I wrote that code.

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Are localposes & offset matrices, and applying those 2 equations above to get global poses really all there is to it or did I miss something?


If you're referring to the paragraph that begins: "Creating a current pose ..." - maybe. wink.png  Depends on what you mean by "current pose, " "localpose," "global pose," where in the process that occurs, and what you're going to do with that matrix. Unfortunately, there isn't a universal set of skinned mesh animation terms. I.e., you may be using "local pose" to mean something different than what I may assume. "Global" implies "world," but you may mean "relative to root frame/bone." (etc.)


First, though, take a look at this article regarding skinned mesh animation. Maybe it will help you with your understanding of the process. Rather than concentrating on the implementation of the code, I'd suggest you glean from it more of how the process works, particularly regarding what each matrix (by whatever name) does with regard to the final process.

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YAAAAAY !!!!!!!!!!!!!!!!!!!!!!!!!!!

I Finally got this to work.

After correcting the way I saved animations it didn't work yet and I was so disappointed and frustrated.

Now it appears I simply had another big bug in how I saved the BLENDINDICES. I saved the index into mBones (wrong, so wrong) instead of into my flattenednode array.


Next step will be to actually interpolate and animate but that's for Monday and the whole of next week :)

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