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OpenGL opengl 2.0

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neither of them have any OpenGL 2.0 drivers out yet. However, according to glView my 6800 Ultra supports about 25% or thereabouts of OpenGL 2.0 already. That's because the nvidia drivers already have ARB_shading_language_100 in and a couple of others. I seem to remember that there are about 4 extensions missing that are required for OpenGL 2.0 support.

However, I should think that my card does support those features, nvidia just hasn't written the driver support for them. I have no idea however how far back in the line 2.0 support goes.

EDIT: according to a quick grep glxinfo | "extensions" and a list of 2.0 extensions from the glView site above, I'm missing GL_ARB_texture_float, GL_ARB_half_float_pixel, GL_ARB_color_clamp_control and GL_ARB_extension_query.

I can't check if I have WGL_ARB_pixel_format_float or not unless I boot back to windows.

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Original post by force_of_will
Acording with glview also my Ati radeon 9700 pro suports about 68%

Quote:
However, according to glView [www.realtech-vr.com] my 6800 Ultra supports about 25% or thereabouts of OpenGL 2.0 already.

Update your drivers guys. You should have full support for everything.
9700 Compliance

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Even my ti4200 appears to support OpenGL2.0 completely (according to glview), is there a way to seperate what's emulated and what's really supported (as fragment shaders themselves are NOT supported)?

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Quote:
Original post by Schmedly
Quote:
Original post by force_of_will
Acording with glview also my Ati radeon 9700 pro suports about 68%

Quote:
However, according to glView [www.realtech-vr.com] my 6800 Ultra supports about 25% or thereabouts of OpenGL 2.0 already.

Update your drivers guys. You should have full support for everything.
9700 Compliance


I have the latest nvidia drivers (67.77). However, my figure of 25% is based on my memory, which isn't the most reliable of things. It could be closer to 70% or something. I do know that it wasn't 100% though.

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Original post by Tree Penguin
Even my ti4200 appears to support OpenGL2.0 completely (according to glview), is there a way to seperate what's emulated and what's really supported (as fragment shaders themselves are NOT supported)?

I was just thinking along the lines of actually being able to find and use the extensions themselves. I believe the actual hardware support is as follows:

DX8 type shaders are GL_ARB_vertex_program / GL_ARB_fragment_program, which would be fully supported on almost any hardware that has a vertex/pixel hardware pipeline (the TI4200 included)

DX9 type shaders are GL_ARB_vertex_shader / GL_ARB_fragment_shader, which would obviously need a DX9 card ala GFFX and up or a Radeon9500 on up

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No, it's the pixelshader 1.3 support the Ti4200 (any GF4 but not MX) has, and not 2.0 (which is the first reasonable and by OpenGL supported PS). It's not full fragment shader functionality, the shaders are converted to NVidia only extensions (texture shaders, registered combiners).

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Original post by baldurk
I have the latest nvidia drivers (67.77). However, my figure of 25% is based on my memory, which isn't the most reliable of things. It could be closer to 70% or something. I do know that it wasn't 100% though.

You're the voice of expertise on that one. I don't have a 6800 to test, but I'd think that all four GLSL necessary extensions (which are what glView lists as 2.0 compliance) should be accessable on those cards. Very interesting.

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Original post by Tree Penguin
No, it's the pixelshader 1.3 support the Ti4200 (any GF4 but not MX) supports. It's not full fragment shader functionality, the shaders are converted to NVidia only extensions (texture shaders, registered combiners).

That's right, I'd forgotten all about that whole 1.3/1.4 support fiasco :) Seems like we're re-living it again with shader model 2.0/3.0.

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Funny, I ran glView an hour ago, and I had 50% openGL 2.0 support, and now I only have 25%...
I have a GeForce FX 5200 with the newest nvidia drivers (at least 4 days ago...). I'm not all into gfx boards and all, but shouldn't the support be a little better?

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there are apprently 16 extensions needed for OGL2.0 compilance (although i suspect a few names will change) as per the newest glview (2.11, build 179 from aug 20th if memory serves), i doubt if any NV driver set has full support and i know ATI doesnt on the 9800 series as i've got one with the cat4.9 drivers and it at 68%

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Original post by _the_phantom_
there are apprently 16 extensions needed for OGL2.0 compilance (although i suspect a few names will change) as per the newest glview (2.11, build 179 from aug 20th if memory serves), i doubt if any NV driver set has full support and i know ATI doesnt on the 9800 series as i've got one with the cat4.9 drivers and it at 68%

Indeed that's a significant change from glView 2.09 which listed only the four shading language extensions. I'm sure there will be another revision of the app since the fully ratified spec isn't available yet. I see GL_EXT_texture_rectangle listed though.. nice. No more power of two size requirements.

So instead of taking my advice an updating drivers.. take phantom's and update glView!

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Yeah, some of you guys need to update your version glView. There are 16 extensions, of which my Geforce 4 Ti 4200 supports 5. Funny, it doesn't even support 1.4 completely, on account of gl_EXT_blend_func_seperate

I HATE my videocard, MF-ing POS.

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The whole concept of these extension viewers is bogus. If your card reports a certain gl version, i.e 1.4, then that is what it supports even though certain features might be done in software. Most current cards doesn't even support all of OpenGL 1.1 in hardware, so if ALL of the API needs to be done in hardware for a card to be "compliant" then no consumer level cards are OpenGL 1.1 compliant. Furthermore, that glView page claims that ARB_Vertex_program is required for OpenGL 1.4 which is false.

As for OpenGL 2.0, NONE of the current gen cards support ALL of the features of the shading language in hardware. That won't stop tehm from having drivers that will report the OpenGL version as 2.0 and accelerate a good portion of the shaders you supply them with though.

To the OP, you can use GLSL via the ARB extension on both ATI's and Nvidia's later cards provided you have the latest drivers. No card can fully claim to support 2.0 yet since the spec isn't finalised.

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Original post by GameCat
The whole concept of these extension viewers is bogus. If your card reports a certain gl version, i.e 1.4, then that is what it supports even though certain features might be done in software. Most current cards doesn't even support all of OpenGL 1.1 in hardware, so if ALL of the API needs to be done in hardware for a card to be "compliant" then no consumer level cards are OpenGL 1.1 compliant. Furthermore, that glView page claims that ARB_Vertex_program is required for OpenGL 1.4 which is false.

That's kind of an extreme interpretation of the purpose of glView. It's not a compliancy test, it's just a reference tool. Something that you can use to see whether or not it's worth your while to write some code on a given video card.

But for a card to be compliant with any version of OpenGL it only has to support the core spec. It is not required to support any amount of extensions not included in the core spec. The whole point of sorting the extensions by OpenGL revision number (that I see) is that it's a reference to when each extension was first introduced as vendor specific or became an ARB extension. There's nothing bogus about that at all because otherwise there would be a chronological mess.

Quote:
As for OpenGL 2.0, NONE of the current gen cards support ALL of the features of the shading language in hardware. That won't stop tehm from having drivers that will report the OpenGL version as 2.0 and accelerate a good portion of the shaders you supply them with though.

I have yet to see an instance of say a 9700 or 9800 not running a shader written (properly) for GL_ARB_shading_language_100 unless it exceeded the temporary register allotment. Could you be more specific about what portions of GLSL aren't supported yet through the 1.5 extensions?

After all though, OpenGL 2.0 != GLSL. The important thing is that GLSL moves to the core spec with OpenGL 2.0, which of course means it has to be supported for the card to be compliant with the new revision.

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Original post by Schmedly
That's kind of an extreme interpretation of the purpose of glView. It's not a compliancy test, it's just a reference tool. Something that you can use to see whether or not it's worth your while to write some code on a given video card.

But for a card to be compliant with any version of OpenGL it only has to support the core spec. It is not required to support any amount of extensions not included in the core spec. The whole point of sorting the extensions by OpenGL revision number (that I see) is that it's a reference to when each extension was first introduced as vendor specific or became an ARB extension. There's nothing bogus about that at all because otherwise there would be a chronological mess.


To be clear, I'm not opposed to extension viewers, only the idea that checking if certain extensions are available can determine OpenGL version "compliancy". This gets even worse when extensions are required to comply with a certain version that weren't promoted to core for that version (like ARB_vertex_program and OpenGL 1.4, it might be an ARB extension, but it isn't required by a 1.4 implementation). If you wan't to sort extensions chronologically, by all means do but don't claim that they are required to support a certain OpenGL version when they aren't.

Quote:
Original post by Schmedly
I have yet to see an instance of say a 9700 or 9800 not running a shader written (properly) for GL_ARB_shading_language_100 unless it exceeded the temporary register allotment. Could you be more specific about what portions of GLSL aren't supported yet through the 1.5 extensions?

After all though, OpenGL 2.0 != GLSL. The important thing is that GLSL moves to the core spec with OpenGL 2.0, which of course means it has to be supported for the card to be compliant with the new revision.


Well, the R300 series certainly can't run all valid shaders in HARDWARE (for example any shader using the partial derivative operators, or the noise function etc). My point was that it is stupid to have full hardware acceleration as some kind of criteria for whether hardware is "fully compliant". I'm sure ATI and Nvidia will have 2.0 drivers for their current and last generation chipsets and that they will accelerate a large and useful portion of GLSL, you'll be able to use them for OpenGL 2.0 development just fine. They won't be able to support (in hardware that is) other things that are likely to be in 2.0 though, like general support for non-power of two textures, but they will still have 2.0 drivers and support OpenGL 2.0 just fine.

Anyway, this discussion is pretty far from the original poster's question so I won't pollute this thread any longer :)

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I dont recall anyone saying that a card has to support something in hardware for it to be fully complient with an OGL version anyways, as long as the driver supports it thats all that matters (example : accum bufffer, been in since at least the 1.1 spec, maybe even 1.0, until the R300/NV30 generation it wasnt supported in hardware at all but was always supported in software)

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      While in earlier APIs shaders were bound separately, in the next-generation APIs as well as in Diligent Engine shaders are part of the pipeline state object. The biggest challenge when authoring shaders is that Direct3D and OpenGL/Vulkan use different shader languages (while Apple uses yet another language in their Metal API). Maintaining two versions of every shader is not an option for real applications and Diligent Engine implements shader source code converter that allows shaders authored in HLSL to be translated to GLSL. To create a shader, one needs to populate ShaderCreationAttribs structure. SourceLanguage member of this structure tells the system which language the shader is authored in:
      SHADER_SOURCE_LANGUAGE_DEFAULT - The shader source language matches the underlying graphics API: HLSL for Direct3D11/Direct3D12 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. SHADER_SOURCE_LANGUAGE_GLSL - The shader source is in GLSL. There is currently no GLSL to HLSL converter, so this value should only be used for OpenGL and OpenGLES modes. There are two ways to provide the shader source code. The first way is to use Source member. The second way is to provide a file path in FilePath member. Since the engine is entirely decoupled from the platform and the host file system is platform-dependent, the structure exposes pShaderSourceStreamFactory member that is intended to provide the engine access to the file system. If FilePath is provided, shader source factory must also be provided. If the shader source contains any #include directives, the source stream factory will also be used to load these files. The engine provides default implementation for every supported platform that should be sufficient in most cases. Custom implementation can be provided when needed.
      When sampling a texture in a shader, the texture sampler was traditionally specified as separate object that was bound to the pipeline at run time or set as part of the texture object itself. However, in most cases it is known beforehand what kind of sampler will be used in the shader. Next-generation APIs expose new type of sampler called static sampler that can be initialized directly in the pipeline state. Diligent Engine exposes this functionality: when creating a shader, textures can be assigned static samplers. If static sampler is assigned, it will always be used instead of the one initialized in the texture shader resource view. To initialize static samplers, prepare an array of StaticSamplerDesc structures and initialize StaticSamplers and NumStaticSamplers members. Static samplers are more efficient and it is highly recommended to use them whenever possible. On older APIs, static samplers are emulated via generic sampler objects.
      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
      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 two samples, asteroids performance benchmark and example Unity project that uses Diligent Engine in native plugin.
      AntTweakBar sample is Diligent Engine’s “Hello World” example.

       
      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 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 and Android platforms. Direct3D11, Direct3D12, OpenGL/GLES backends are now feature complete. Vulkan backend is coming next, and support for more platforms is planned.
    • By michaeldodis
      I've started building a small library, that can render pie menu GUI in legacy opengl, planning to add some traditional elements of course.
      It's interface is similar to something you'd see in IMGUI. It's written in C.
      Early version of the library
      I'd really love to hear anyone's thoughts on this, any suggestions on what features you'd want to see in a library like this? 
      Thanks in advance!
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