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Voxel Cone Tracing constraints and flexibility

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Hi all. I have been looking for a real-time global illumination algorithm to use in my game. I've found voxel cone tracing and I'm debating whether or not it's an algorithm worth investing my time researching and implementing. I have this doubt due to the following reasons:

. I see a lot of people say it's really hard to implement.

. Apparently this algorithm requires some Nvidia extension to work efficiently according to the original paper (I highly doubt it though)

. Barely real-time performance, meaning it's too slow to be implemented in a game 

 

So in order to determine if I should invest time in voxel cone tracing, I want to ask the following questions:

. Is the algorithm itself flexible enough so that I can increase the performance by tweaking it (probably lowering the GI quality at the same time, but I don't care)

. Can I implement it without any driver requirement or special extensions, like the paper claims?

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The Nvidia paper is... unreliable. Cone tracing is potentially fast, the problem is lightleak makes its hard to implement reliably. By cone tracing's nature the farther you trace the more lightleak you get. But the shorter a cone you trace the less light you get, overall it was an idea that seemed like the future two+ years ago but has since fallen out due to its weaknesses.

There are a lot of other GI techniques that can be considered depending on your requirements. EG is the environment static, or highly deformable, or runtime generated? Does light need to move fast or can it move slowly (EG a slow time of day?).

That being said Signed Distance Field tracing and some version of lightcuts/many lights looks like it could, potentially, do what cone tracing once promised in realtime. Here's a nice presentation on signed distance fields, which is essentially a sparse voxel octree from cone tracing but you "sphere trace" instead of doing a cone. Benefits therein being no lightleak. Lightcuts/VPLs/"Many Lights" would be other half of the equation. Here's a nice presentation from Square Enix, wherein the biggest cost they have in the test scene is their choice of "adaptive imperfect shadow maps" which is a really hacky and slow way to do what SDF tracing can do easier and faster.

Edited by FreneticPonE

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Thank you for your insight. It seems like I have to reconsider what GI algorithm to use. This is the constraints in my game:

. Single directional light source. It never changes.

. Mesh is mostly static except for characters that run around. 

. I want one bounce of diffuse indirect light. 

 

I'd appreciate it if you can suggest the GI algorithm that fits my criteria. Thank you for your answers. 

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1 hour ago, MonterMan said:

. Apparently this algorithm requires some Nvidia extension to work efficiently according to the original paper (I highly doubt it though)

The extension (conservative rasterization - i think AMD Vega has it finally) is not necessary. You can use geometry shader to extend triangles (slower of course). You can also accept some holes and ignore this completely, because light will leak anyways.

In addition to Frentics response: Voxelization requires LODs in practice, which means it always breaks down at distance. Empty space between two walls vanishes and becomes entirely solid, so no light reaches that space. That's the opposite of leaking light but comes from the same limitations.

6 minutes ago, MonterMan said:

Thank you for your insight. It seems like I have to reconsider what GI algorithm to use. This is the constraints in my game:

. Single directional light source. It never changes.

. Mesh is mostly static except for characters that run around. 

. I want one bounce of diffuse indirect light. 

Baking makes sense. How dynamic is your lighting? Time of day? Moving sun? Mainly interiors with static lighting?

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Lighting is completely static. Sun never moves and it's always the same time of day. Mainly outdoor scenes with small buildings that have interior. 

 

Thanks for the additional info on voxel cone tracing's shortcomings. 

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There seems totally no need for any kind of real time GI, not even something supporting just dynamic lights on static world.

So you could bake everything to lightmaps, but there are many options on what to store in a texel:

Just diffuse like Quake3 did.

Add a primary light direction to support normal mapping.

Store full enviroment to support full BRDF.

See here for Introduction and details: https://mynameismjp.wordpress.com/2016/10/09/new-blog-series-lightmap-baking-and-spherical-gaussians/

 

For dynamic objects you could use irradiance probes,

either placed in a grid,

or placed by hand with some radius (or shape) of influence,

or interpolationg 4 closest hand placed ones from a voroni tetrahedralization.

 

You could also merge those static / dynamic approaches like Quantum Break did (they use voxels instead lightmap texels): https://users.aalto.fi/~silvena4/Publications/SIGGRAPH_2015_Remedy_Notes.pdf

 

For reflections probes are state of the art, with the same options as listed for dynamic objects above. Extended with screen space raytracing.

 

So... some work. Probably not really easier to implement than voxel cone tracing (work goes into pre-processing tools), but faster, higher quality, and much less issues.

 

Edit: The difference between one bounce and infinite bounces can be night and day in interiors, so don't forget to utilize this if you go baked.

 

 

 

Edited by JoeJ

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Got it. I was initially looking for a real-time GI algorithm because I didn't want do a separate preprocess step. But now it seems like baking is the way to go to achieve the highest quality, so it's worth it. Thank you for the awesome resources. That's indeed some work, but it's going to be worth it in the end :). 

 

I actually looked into baking lightmaps before, one that caught my attention is the light precomputation in The Witness: https://web.archive.org/web/20170227054745/http://the-witness.net/news/2010/09/hemicube-rendering-and-integration/ that is based on a radiosity algorithm: https://web.archive.org/web/20120324095518/http://freespace.virgin.net/hugo.elias/radiosity/radiosity.htm.

But I gave up on the above methods because they require a ton of tweaking to get the result just right, so I looked into real-time stuff instead. 

 

Again thanks for the help guys, now it's pretty clear to me what to do. 

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The Witness tool to get automatic UVs is on github: https://github.com/Thekla/thekla_atlas

But Microsofts UV Atlas is also pretty nice, maybe better: https://github.com/Microsoft/UVAtlas

Form that you could get a 'surfel' representation of the scene (disks with the area and the normal for each lightmap texel).

Then calculating diffuse lighting is easy to understand, like my 'educational' code below. Tracing for visibility is missing, if you add this with some tree for acceleration you already have a solution. (each call To simulateOneBounce adds one bounce so accuracy increases.)

 

	struct Radiosity
{
    typedef sVec3 vec3;
    inline vec3 cmul (const vec3 &a, const vec3 &b)
    {
        return vec3 (a[0]*b[0], a[1]*b[1], a[2]*b[2]); 
    }
	
    struct AreaSample
    {
        vec3 pos;            
        vec3 dir;            
        float area;
	        vec3 color;            
        vec3 received;        
        float emission; // using just color * emission to save memory
    };
	    AreaSample *samples;
    int sampleCount;
	    void InitScene ()
    {
        // simple cylinder
	        int nU = 144;
        int nV = int( float(nU) / float(PI) );
        float scale = 2.0f;
                
        float area = (2 * scale / float(nU) * float(PI)) * (scale / float(nV) * 2); 
            
        sampleCount = nU*nV;
        samples = new AreaSample[sampleCount];
	        AreaSample *sample = samples;
        for (int v=0; v<nV; v++)
        {
            float tV = float(v) / float(nV);
	            for (int u=0; u<nU; u++)
            {
                float tU = float(u) / float(nU);
                float angle = tU * 2.0f*float(PI);
                vec3 d (sin(angle), 0, cos(angle));
                vec3 p = (vec3(0,tV*2,0) + d) * scale;
	                sample->pos = p;
                sample->dir = -d;
                sample->area = area;
	                sample->color = ( d[0] < 0 ? vec3(0.7f, 0.7f, 0.7f) : vec3(0.0f, 1.0f, 0.0f) );
                sample->received = vec3(0,0,0);
                sample->emission = ( (d[0] < -0.97f && tV > 0.87f) ? 35.0f : 0 );
	                sample++;
            }
        }
    }
	    void SimulateOneBounce ()
    {
        for (int rI=0; rI<sampleCount; rI++) 
        {
            vec3 rP = samples[rI].pos;
            vec3 rD = samples[rI].dir;
            vec3 accum (0,0,0);
	            for (int eI=0; eI<sampleCount; eI++)
            {
                vec3 diff = samples[eI].pos - rP;
	                float cosR = rD.Dot(diff);
                if (cosR > FP_EPSILON)
                {
                    float cosE = -samples[eI].dir.Dot(diff);
                    if (cosE > FP_EPSILON)
                    {
                        float visibility = 1.0f; // todo: In this example we know each surface sees any other surface, but in Practice: Trace a ray from receiver to emitter and set to zero if any hit (or use multiple rays for accuracy)
	                        if (visibility > 0)
                        {
                            float area = samples[eI].area;
                            float d2 = diff.Dot(diff) + FP_TINY;
                            float formFactor = (cosR * cosE) / (d2 * (float(PI) * d2 + area)) * area;
                        
                            vec3 reflect = cmul (samples[eI].color, samples[eI].received);
                            vec3 emit = samples[eI].color * samples[eI].emission;
                            
                            accum += (reflect + emit) * visibility * formFactor;
                        }
                    }            
                }
            }
            
            samples[rI].received = accum;
        }
    }
	    void Visualize ()
    {
        for (int i=0; i<sampleCount; i++)
        {
            vec3 reflect = cmul (samples[i].color, samples[i].received);
            vec3 emit = samples[i].color * samples[i].emission;
	            vec3 color = reflect + emit;
	            //float radius = sqrt (samples[i].area / float(PI));
            //Vis::RenderCircle (radius, samples[i].pos, samples[i].dir, color[0],color[1],color[2]); 
            
            float radius = sqrt(samples[i].area * 0.52f);
            Vis::RenderDisk (radius, samples[i].pos, samples[i].dir, color[0],color[1],color[2], 4); // this renders a quad
        }
    }
	};
	

 

 

 

 

 

Edited by JoeJ

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I forgot to mention the  alternative to the above.

You could just export your scene to a 3D rendering tool like Blender, use its automatic UV unwrapping, bake stuff and done. This should be automatable and much less work.

I do not know how and if it is possible to get directional lighting information but i assume there are options.

 

...or you use something like Mitsuba / Embree to calculate lighting. That sounds felxible enough and no unsolveable issues could pop up.

 

 

Edited by JoeJ

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With voxel cone tracing your result will look like something like this (to show something you can expect with real time GI):

tmp.thumb.png.e1e3b3dc8eceb8a29501fd1f79e53f98.png

Which is single-bounce dynamic indirect illumination, and you can also re-use these for reflections. Notice-able flaws:

  • Light-bleeding (on the bottom-right side, light bleeding for green model is notice-able in shadowed area)
  • Dark shadows (especially cast by the object in the middle - this is due to only single-bounce global illumination)
  • Visible aliasing (even though using 8x MSAA, due to GI being computed in non-MSAA buffer - aliasing is going to be visible, I intentionally didn't use any more-hacky method for upsampling
  • Some details not contributing to global illumination (due to low voxel resolution)

 

So far I've tried multiple solutions for GI over the years, and nothing can beat unbiased methods (Path Tracing or Progressive Photon Mapping), yet those require a lot of samples to converge. Out of other methods (Reflective Shadow Mapping + Imperfect Shadow Maps being another method that had acceptable quality results), Voxel Cone Tracing is a winner for me in terms of quality and performance.

Of course pre-computed methods are another chapter, which are not really applicable to my case though.

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@Vilem Otte Nice, you can also extend that to support multiple bounces too which is quite straight forward, doing additional cone traces from every voxel.

Also voxel cone tracing have been already used by games such as Tomorrow Children on PS4, which also has some slides detailing their implementation: http://fumufumu.q-games.com/archives/Cascaded_Voxel_Cone_Tracing_final.pdf They eliminate light bleeding by using anisotropic voxels storing different radiance for different directions.
And I think the latest Tomb Raider also uses some voxel based ambient occlusion.

But for @MonterMan 's case with static lighting I agree that this is overkill and lightmaps will provide much more detail for much less performance and much easier to implement.

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@turanszkij Anisotropic voxels or multiple bounces tend to be quite large performance hit for me (bleeding is close to invisible for me in most scenes I have - plus when you're actually moving in game, it is hardly notice-able ... so basically as they don't really have major impact for my scenes, I don't have any reason to waste computing power on those). The big difference compared to Tomorrow Children implementation is using shadow maps (even for voxel data).

When I want to do it correctly, I still have GPU-based unbiased bidirectional path tracer. The only downside is, that it takes up to few seconds to generate smooth image.

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      Creating the Pipeline State Object
      After all required shaders are created, the rest of the fields of the PipelineStateDesc structure provide depth-stencil, rasterizer, and blend state descriptions, the number and format of render targets, input layout format, etc. For instance, rasterizer state can be described as follows:
      PipelineStateDesc PSODesc; RasterizerStateDesc &RasterizerDesc = PSODesc.GraphicsPipeline.RasterizerDesc; RasterizerDesc.FillMode = FILL_MODE_SOLID; RasterizerDesc.CullMode = CULL_MODE_NONE; RasterizerDesc.FrontCounterClockwise = True; RasterizerDesc.ScissorEnable = True; RasterizerDesc.AntialiasedLineEnable = False; Depth-stencil and blend states are defined in a similar fashion.
      Another important thing that pipeline state object encompasses is the input layout description that defines how inputs to the vertex shader, which is the very first shader stage, should be read from the memory. Input layout may define several vertex streams that contain values of different formats and sizes:
      // Define input layout InputLayoutDesc &Layout = PSODesc.GraphicsPipeline.InputLayout; LayoutElement TextLayoutElems[] = {     LayoutElement( 0, 0, 3, VT_FLOAT32, False ),     LayoutElement( 1, 0, 4, VT_UINT8, True ),     LayoutElement( 2, 0, 2, VT_FLOAT32, False ), }; Layout.LayoutElements = TextLayoutElems; Layout.NumElements = _countof( TextLayoutElems ); Finally, pipeline state defines primitive topology type. When all required members are initialized, a pipeline state object can be created by IRenderDevice::CreatePipelineState() method:
      // Define shader and primitive topology PSODesc.GraphicsPipeline.PrimitiveTopologyType = PRIMITIVE_TOPOLOGY_TYPE_TRIANGLE; PSODesc.GraphicsPipeline.pVS = pVertexShader; PSODesc.GraphicsPipeline.pPS = pPixelShader; PSODesc.Name = "My pipeline state"; m_pDev->CreatePipelineState(PSODesc, &m_pPSO); When PSO object is bound to the pipeline, the engine invokes all API-specific commands to set all states specified by the object. In case of Direct3D12 this maps directly to setting the D3D12 PSO object. In case of Direct3D11, this involves setting individual state objects (such as rasterizer and blend states), shaders, input layout etc. In case of OpenGL, this requires a number of fine-grain state tweaking calls. Diligent Engine keeps track of currently bound states and only calls functions to update these states that have actually changed.
      Binding Shader Resources
      Direct3D11 and OpenGL utilize fine-grain resource binding models, where an application binds individual buffers and textures to certain shader or program resource binding slots. Direct3D12 uses a very different approach, where resource descriptors are grouped into tables, and an application can bind all resources in the table at once by setting the table in the command list. Resource binding model in Diligent Engine is designed to leverage this new method. It introduces a new object called shader resource binding that encapsulates all resource bindings required for all shaders in a certain pipeline state. It also introduces the classification of shader variables based on the frequency of expected change that helps the engine group them into tables under the hood:
      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. Shader variable type must be specified during shader creation by populating an array of ShaderVariableDesc structures and initializing ShaderCreationAttribs::Desc::VariableDesc and ShaderCreationAttribs::Desc::NumVariables members (see example of shader creation above).
      Static variables cannot be changed once a resource is bound to the variable. They are bound directly to the shader object. For instance, a shadow map texture is not expected to change after it is created, so it can be bound directly to the shader:
      PixelShader->GetShaderVariable( "g_tex2DShadowMap" )->Set( pShadowMapSRV ); Mutable and dynamic variables are bound via a new Shader Resource Binding object (SRB) that is created by the pipeline state (IPipelineState::CreateShaderResourceBinding()):
      m_pPSO->CreateShaderResourceBinding(&m_pSRB); Note that an SRB is only compatible with the pipeline state it was created from. SRB object inherits all static bindings from shaders in the pipeline, but is not allowed to change them.
      Mutable resources can only be set once for every instance of a shader resource binding. Such resources are intended to define specific material properties. For instance, a diffuse texture for a specific material is not expected to change once the material is defined and can be set right after the SRB object has been created:
      m_pSRB->GetVariable(SHADER_TYPE_PIXEL, "tex2DDiffuse")->Set(pDiffuseTexSRV); In some cases it is necessary to bind a new resource to a variable every time a draw command is invoked. Such variables should be labeled as dynamic, which will allow setting them multiple times through the same SRB object:
      m_pSRB->GetVariable(SHADER_TYPE_VERTEX, "cbRandomAttribs")->Set(pRandomAttrsCB); Under the hood, the engine pre-allocates descriptor tables for static and mutable resources when an SRB objcet is created. Space for dynamic resources is dynamically allocated at run time. Static and mutable resources are thus more efficient and should be used whenever possible.
      As you can see, Diligent Engine does not expose low-level details of how resources are bound to shader variables. One reason for this is that these details are very different for various APIs. The other reason is that using low-level binding methods is extremely error-prone: it is very easy to forget to bind some resource, or bind incorrect resource such as bind a buffer to the variable that is in fact a texture, especially during shader development when everything changes fast. Diligent Engine instead relies on shader reflection system to automatically query the list of all shader variables. Grouping variables based on three types mentioned above allows the engine to create optimized layout and take heavy lifting of matching resources to API-specific resource location, register or descriptor in the table.
      This post gives more details about the resource binding model in Diligent Engine.
      Setting the Pipeline State and Committing Shader Resources
      Before any draw or compute command can be invoked, the pipeline state needs to be bound to the context:
      m_pContext->SetPipelineState(m_pPSO); Under the hood, the engine sets the internal PSO object in the command list or calls all the required native API functions to properly configure all pipeline stages.
      The next step is to bind all required shader resources to the GPU pipeline, which is accomplished by IDeviceContext::CommitShaderResources() method:
      m_pContext->CommitShaderResources(m_pSRB, COMMIT_SHADER_RESOURCES_FLAG_TRANSITION_RESOURCES); The method takes a pointer to the shader resource binding object and makes all resources the object holds available for the shaders. In the case of D3D12, this only requires setting appropriate descriptor tables in the command list. For older APIs, this typically requires setting all resources individually.
      Next-generation APIs require the application to track the state of every resource and explicitly inform the system about all state transitions. For instance, if a texture was used as render target before, while the next draw command is going to use it as shader resource, a transition barrier needs to be executed. Diligent Engine does the heavy lifting of state tracking.  When CommitShaderResources() method is called with COMMIT_SHADER_RESOURCES_FLAG_TRANSITION_RESOURCES flag, the engine commits and transitions resources to correct states at the same time. Note that transitioning resources does introduce some overhead. The engine tracks state of every resource and it will not issue the barrier if the state is already correct. But checking resource state is an overhead that can sometimes be avoided. The engine provides IDeviceContext::TransitionShaderResources() method that only transitions resources:
      m_pContext->TransitionShaderResources(m_pPSO, m_pSRB); In some scenarios it is more efficient to transition resources once and then only commit them.
      Invoking Draw Command
      The final step is to set states that are not part of the PSO, such as render targets, vertex and index buffers. Diligent Engine uses Direct3D11-syle API that is translated to other native API calls under the hood:
      ITextureView *pRTVs[] = {m_pRTV}; m_pContext->SetRenderTargets(_countof( pRTVs ), pRTVs, m_pDSV); // Clear render target and depth buffer const float zero[4] = {0, 0, 0, 0}; m_pContext->ClearRenderTarget(nullptr, zero); m_pContext->ClearDepthStencil(nullptr, CLEAR_DEPTH_FLAG, 1.f); // 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); Different native APIs use various set of function to execute draw commands depending on command details (if the command is indexed, instanced or both, what offsets in the source buffers are used etc.). For instance, there are 5 draw commands in Direct3D11 and more than 9 commands in OpenGL with something like glDrawElementsInstancedBaseVertexBaseInstance not uncommon. Diligent Engine hides all details with single IDeviceContext::Draw() method that takes 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); For compute commands, there is IDeviceContext::DispatchCompute() method that takes DispatchComputeAttribs structure that defines compute grid dimension.
      Source Code
      Full engine source code is available on GitHub and is free to use. The repository contains tutorials, sample applications, asteroids performance benchmark and an example Unity project that uses Diligent Engine in native plugin.
      Atmospheric scattering sample demonstrates how Diligent Engine can be used to implement various rendering tasks: loading textures from files, using complex shaders, rendering to multiple render targets, using compute shaders and unordered access views, etc.

      Asteroids performance benchmark is based on this demo developed by Intel. It renders 50,000 unique textured asteroids and allows comparing performance of Direct3D11 and Direct3D12 implementations. Every asteroid is a combination of one of 1000 unique meshes and one of 10 unique textures.

      Finally, there is an example project that shows how Diligent Engine can be integrated with Unity.

      Future Work
      The engine is under active development. It currently supports Windows desktop, Universal Windows, Linux, Android, MacOS, and iOS platforms. Direct3D11, Direct3D12, OpenGL/GLES backends are now feature complete. Vulkan backend is coming next, and Metal backend is in the plan.
    • By francoisdiy
      So I wrote a programming language called C-Lesh to program games for my game maker Platformisis. It is a scripting language which tiles into the JavaScript game engine via a memory mapper using memory mapped I/O. Currently, I am porting the language as a standalone interpreter to be able to run on the PC and possibly other devices excluding the phone. The interpreter is being written in C++ so for those of you who are C++ fans you can see the different components implemented. Some background of the language and how to program in C-Lesh can be found here:

      http://www.codeloader.net/readme.html
      As I program this thing I will post code from different components and explain.
    • By _RoboCat_
      Hi,
      Can anyone point me into good direction how to resolve this?
      I have flat mesh made from many quads (size 1x1 each) each split into 2 triangles. (made procedural)
      What i want to achieve is : "merge" small quads into bigger ones (show on picture 01), English is not my mother language and my search got no result... maybe i just form question wrong.
      i have array[][] where i store "map" information, for now i'm looking for blobs of same value in it -> and then for each position i create 1 quad. and on end create mesh from all.
      is there any good algorithm for creating mesh between random points on same plane? less triangles better. Or "de-tesselate" this to bigger/less triangles/quads?
      Also i would like to find "edges" and create "faces" between edge points (picture 02 shows what i want to achieve).
      No need for whole code, just if someone can point me in good direction would be nice.
      Thanks


    • By isu diss
      I'm trying to duplicate vertices using std::map to be used in a vertex buffer. I don't get the correct index buffer(myInds) or vertex buffer(myVerts). I can get the index array from FBX but it differs from what I get in the following std::map code. Any help is much appreciated.
      struct FBXVTX { XMFLOAT3 Position; XMFLOAT2 TextureCoord; XMFLOAT3 Normal; }; std::map< FBXVTX, int > myVertsMap; std::vector<FBXVTX> myVerts; std::vector<int> myInds; HRESULT FBXLoader::Open(HWND hWnd, char* Filename, bool UsePositionOnly) { HRESULT hr = S_OK; if (FBXM) { FBXIOS = FbxIOSettings::Create(FBXM, IOSROOT); FBXM->SetIOSettings(FBXIOS); FBXI = FbxImporter::Create(FBXM, ""); if (!(FBXI->Initialize(Filename, -1, FBXIOS))) { hr = E_FAIL; MessageBox(hWnd, (wchar_t*)FBXI->GetStatus().GetErrorString(), TEXT("ALM"), MB_OK); } FBXS = FbxScene::Create(FBXM, "REALMS"); if (!FBXS) { hr = E_FAIL; MessageBox(hWnd, TEXT("Failed to create the scene"), TEXT("ALM"), MB_OK); } if (!(FBXI->Import(FBXS))) { hr = E_FAIL; MessageBox(hWnd, TEXT("Failed to import fbx file content into the scene"), TEXT("ALM"), MB_OK); } FbxAxisSystem OurAxisSystem = FbxAxisSystem::DirectX; FbxAxisSystem SceneAxisSystem = FBXS->GetGlobalSettings().GetAxisSystem(); if(SceneAxisSystem != OurAxisSystem) { FbxAxisSystem::DirectX.ConvertScene(FBXS); } FbxSystemUnit SceneSystemUnit = FBXS->GetGlobalSettings().GetSystemUnit(); if( SceneSystemUnit.GetScaleFactor() != 1.0 ) { FbxSystemUnit::cm.ConvertScene( FBXS ); } if (FBXI) FBXI->Destroy(); FbxNode* MainNode = FBXS->GetRootNode(); int NumKids = MainNode->GetChildCount(); FbxNode* ChildNode = NULL; for (int i=0; i<NumKids; i++) { ChildNode = MainNode->GetChild(i); FbxNodeAttribute* NodeAttribute = ChildNode->GetNodeAttribute(); if (NodeAttribute->GetAttributeType() == FbxNodeAttribute::eMesh) { FbxMesh* Mesh = ChildNode->GetMesh(); if (UsePositionOnly) { NumVertices = Mesh->GetControlPointsCount();//number of vertices MyV = new XMFLOAT3[NumVertices]; for (DWORD j = 0; j < NumVertices; j++) { FbxVector4 Vertex = Mesh->GetControlPointAt(j);//Gets the control point at the specified index. MyV[j] = XMFLOAT3((float)Vertex.mData[0], (float)Vertex.mData[1], (float)Vertex.mData[2]); } NumIndices = Mesh->GetPolygonVertexCount();//number of indices MyI = (DWORD*)Mesh->GetPolygonVertices();//index array } else { FbxLayerElementArrayTemplate<FbxVector2>* uvVertices = NULL; Mesh->GetTextureUV(&uvVertices); int idx = 0; for (int i = 0; i < Mesh->GetPolygonCount(); i++)//polygon(=mostly triangle) count { for (int j = 0; j < Mesh->GetPolygonSize(i); j++)//retrieves number of vertices in a polygon { FBXVTX myVert; int p_index = 3*i+j; int t_index = Mesh->GetTextureUVIndex(i, j); FbxVector4 Vertex = Mesh->GetControlPointAt(p_index);//Gets the control point at the specified index. myVert.Position = XMFLOAT3((float)Vertex.mData[0], (float)Vertex.mData[1], (float)Vertex.mData[2]); FbxVector4 Normal; Mesh->GetPolygonVertexNormal(i, j, Normal); myVert.Normal = XMFLOAT3((float)Normal.mData[0], (float)Normal.mData[1], (float)Normal.mData[2]); FbxVector2 uv = uvVertices->GetAt(t_index); myVert.TextureCoord = XMFLOAT2((float)uv.mData[0], (float)uv.mData[1]); if ( myVertsMap.find( myVert ) != myVertsMap.end() ) myInds.push_back( myVertsMap[ myVert ]); else { myVertsMap.insert( std::pair<FBXVTX, int> (myVert, idx ) ); myVerts.push_back(myVert); myInds.push_back(idx); idx++; } } } } } } } else { hr = E_FAIL; MessageBox(hWnd, TEXT("Failed to create the FBX Manager"), TEXT("ALM"), MB_OK); } return hr; } bool operator < ( const FBXVTX &lValue, const FBXVTX &rValue) { if (lValue.Position.x != rValue.Position.x) return(lValue.Position.x < rValue.Position.x); if (lValue.Position.y != rValue.Position.y) return(lValue.Position.y < rValue.Position.y); if (lValue.Position.z != rValue.Position.z) return(lValue.Position.z < rValue.Position.z); if (lValue.TextureCoord.x != rValue.TextureCoord.x) return(lValue.TextureCoord.x < rValue.TextureCoord.x); if (lValue.TextureCoord.y != rValue.TextureCoord.y) return(lValue.TextureCoord.y < rValue.TextureCoord.y); if (lValue.Normal.x != rValue.Normal.x) return(lValue.Normal.x < rValue.Normal.x); if (lValue.Normal.y != rValue.Normal.y) return(lValue.Normal.y < rValue.Normal.y); return(lValue.Normal.z < rValue.Normal.z); }  
    • By Karol Plewa
      Hi, 
       
      I am working on a project where I'm trying to use Forward Plus Rendering on point lights. I have a simple reflective scene with many point lights moving around it. I am using effects file (.fx) to keep my shaders in one place. I am having a problem with Compute Shader code. I cannot get it to work properly and calculate the tiles and lighting properly. 
       
      Is there anyone that is wishing to help me set up my compute shader?
      Thank you in advance for any replies and interest!
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