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OpenGL Accessing video memory in c++

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Hey...I would like to make my own 3d graphics library (just a hobby project, so please don't tell me to use direct3d or opengl or any of those stuff). So, how would I access video memory directly in Windows, or can I only draw inside a frame? If so, how can I use the WinAPI to do this? Thanks in advice!

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You can't access video memory directly. Usually the closest thing is to create a Direct3D surface/backbuffer, lock it, and write manually. Then you can flip that to screen. You could use a GDI construct like an HBITMAP instead, but it will be slower for no advantage.

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ok,thanks, but is it possible to draw individual pixels in the WinAPI, without having to get the DirectX sdk, wasting a bunch of RAM, etc? I'm trying to not use an existing 3d engine to make this.

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Original post by Phynix
ok,thanks, but is it possible to draw individual pixels in the WinAPI, without having to get the DirectX sdk, wasting a bunch of RAM, etc? I'm trying to not use an existing 3d engine to make this.
PixelToaster might be more what you are looking for - a simple framework providing pixel-access to a framebuffer.

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Isn't that just a wrapper around Direct3D? Maybe that's fine for the OP's purposes, although he sounded like he didn't even want to have any sort of dependency on D3D. In which case, I'm not sure it's possible without a kernel driver and a ton of work.

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yeah, it would be preferable if there was no Direct3D dependancy, but if there is nothing else...which i really doubt...then, i would just have to settle with d3d. what im sort of asking is if you can draw directly to a winapi window.

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Quote:
Original post by Phynix
ok,thanks, but is it possible to draw individual pixels in the WinAPI, without having to get the DirectX sdk, wasting a bunch of RAM, etc? I'm trying to not use an existing 3d engine to make this.
No, you can't directly access the hardware in any modern operating system. Physical access to hardware is controlled via the kernel (to understand why, just think: what would happen if two programs wanted to access the hardware at the same time?)

You can draw bitmaps to the screen with plain old GDI/GDI+ of course (e.g. with BitBlt in GDI), but you won't be "access[ing] video memory directly". Libraries such as SDL also provide a simple API for drawing 2D images in a cross-platform way, perhaps you can start there?

In particular, if you're wanting to write your own software rasterizer, you don't actually need "direct" access to video memory, and I would say that the interface provided by SDL would be more than sufficient for your scenario.

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You don't access to the hardware directly. Leave that to the driver.
Besides even if you could, each video card model is different, and you would need to code for each and every one.
Instead, there IS already an interface to the driver: it's called Direct3D.

Direct3D is a low-level API that allows you to access the video card in a generic way. It's NOT an engine.
Over time Direct3D grew and now it's bigger and contains a lot of stuff usefull for game developers, but it doesn't make it an engine. It's still a low level API.

Furthermore, everything that is not truly necessary is in the D3DX library, stay away from D3DX and it will be fine.

You can try GDI instead, which is another, older, interface.
But I don't understand why you want to stay away from D3D.

Cheers
Dark Sylinc

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In the old days, you could access the actual video memory directly (mode 13h FTW), but these days you can't. More importantly, you probably don't want to, because you have to play nice with your windowing environment.

What you most probably mean is that you want a single, contiguous block of memory that can be used as a suitable linear framebuffer for software rendering/rasterization.

The Win32 APIs give you enough to do just this -- in fact, its exactly the way that WinG, which was the precursor to DirectX, worked in order to entice game developers to move away from DOS. The Previously mentioned PixelToaster does exactly what you want and supports multiple platforms, IIRC.


My own software rendering system works completely independently of any OS API up until I need to get my back-buffer onto the screen, and the sum total of Windows API code, aside from window creation, involved in getting my results to the screen is about 12 lines. It supports both windowed and fullscreen rendering.

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Quote:
Original post by Matias Goldberg
You can try GDI instead, which is another, older, interface.
But I don't understand why you want to stay away from D3D.


OK, I will try GDI, thanks. I also found a great tutorail on the web by googling (http://www.functionx.com/win32/index.htm), and is pretty close to what I originally wanted: a method of manipulating pixels using the Win32 API.

And the reason I wanted to stay away from D3D is because it would be redundant. I don't find any point in creating D3D from D3D (creating a graphics library that has the same or less functionality than the thing it was based upon). Direct3D is already a 3D library, and it doesn't make sense to make a 3D library out of a 3D library.

So, my question is pretty much answered. Thanks Matias Goldberg and Codeka, and everyone else. (Wow, I love these forums)

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Original post by Phynix
And the reason I wanted to stay away from D3D is because it would be redundant. I don't find any point in creating D3D from D3D (creating a graphics library that has the same or less functionality than the thing it was based upon). Direct3D is already a 3D library, and it doesn't make sense to make a 3D library out of a 3D library.
Thus why you should use PixelToaster, rather than mucking about with GDI. PixelToaster will abstract away all the little details that don't matter to your 3D engine, and probably perform better than GDI into the bargain [smile]

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Original post by EngineCoder
Why not simply use SDL?


If you don't know any of them, and are only looking out to stuffing some surface with pixels, then pixel-toaster might be the easier and more appropriate choice.

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So you're going to use D3D, via pixeltoaster, to write a D3D-like API/library? Why?

Quote:
is it possible to draw individual pixels in the WinAPI, without having to get the DirectX sdk, wasting a bunch of RAM, etc?


Your plan is hardly going to improve your memory usage. I don't think anyone really understands why you want to do this. If it's for your own understanding, then why are you so averse to using D3D? If it's to try to create a usable 3D API then it's hardly worth bothering, as you're not going to be able to better D3D or OpenGL, which have access to the graphics hardware through the graphics drivers.

Basically you are going to have to use D3D or OpenGL at some level to get your graphics data to the graphics card's display memory, even if you do all the rendering with the CPU.

EDIT: If you really want to write your own software renderer, then use D3D with a lockable backbuffer, and just change the backbuffer pixels in memory (perhaps using a simple #define macro). It's not a very good way to draw 3D graphics, but then ignoring the graphics card's capabilities isn't a very good way to draw 3D graphics either. That way, you'll be only be using D3D to get a pointer to the video memory. You can't really get any further from using it than that.

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Original post by EngineCoder
Why not simply use SDL?
Because PixelToaster is optimised for software rasterisers/ray-tracers, while SDL is designed for sprite blitting. The performance difference may be negligible, but PixelToaster is a lot simpler to use (don't have to worry about surface formats, etc.).

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Original post by stonemetal
Or better yet look at the code in SDL and pixeltoaster(if it is open) and aim for as low a level as possible.


Why would that be better?

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Original post by stonemetal
Or better yet look at the code in SDL and pixeltoaster(if it is open) and aim for as low a level as possible.
Not sure why you'd want to do that. If the goal is a software rasterizer (which is what it seems to be) then doing all the "low-level" stuff would just be a waste of time. You're much better off using something like PixelToaster to handle that for you and just work with the flat buffer it gives you. Then you can concentrate on all the "interesting" stuff!

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One downside to PixelToaster is that it only supports 32bit ARGB and 128bit (4xfloat) ARGB color formats. Granted 32bit is pretty standard, even for software renderers, but going to 16bit color can essentially double your fill-rate for free.

If you want to support 16bit (or even 8bit CLUT) color formats, you'll need to go through GDI/Win32.

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I like to do char *myScreen = new char[height*width*3], and draw to that. Then you can copy that to your window however you like, it can easily be implemented separate from the rest of your game in all the mentioned APIs. The easiest probably being StretchDIBits in Win32, which with a single function call puts those pixels in the window.

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I hate to sound asinine, but maybe you would have better luck accessing video memory directly if you used a hacked-up version of the Linux kernel. I think the linear frame buffer is still there on x86 machines at 0x0000a0000. It's also easier to write a device driver under Linux than Windows.

Short of that the only way your going to access the video memory directly is if you write your own operating system and/or your own video driver. Like one of the poster's above mentioned if you *DID* write your own video driver, the API to it would be your replacement to D3D (except for the fact that it would only work with one specific type of hardware, whereas D3D is generic enough to interface with 99.9% of existing video cards).

Or you could just roll your own mini-os that has no purpose except to access video memory. Another alternative would be to create a Windows program that was compiled using the Boot Environment Application subsystem, that gives pretty raw access to the video buffer (through Bg/Bl APIs) but is largely undocumented. So you could write your whole program there and the machine would hit the BIOS then the POST, then your Boot program and as long as you keep it from exiting back to bootmgfw then your program would be the one and only!

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Original post by Steve_Segreto
I hate to sound asinine, but maybe you would have better luck accessing video memory directly if you used a hacked-up version of the Linux kernel. I think the linear frame buffer is still there on x86 machines at 0x0000a0000. It's also easier to write a device driver under Linux than Windows.

Short of that the only way your going to access the video memory directly is if you write your own operating system and/or your own video driver. Like one of the poster's above mentioned if you *DID* write your own video driver, the API to it would be your replacement to D3D (except for the fact that it would only work with one specific type of hardware, whereas D3D is generic enough to interface with 99.9% of existing video cards).

Or you could just roll your own mini-os that has no purpose except to access video memory. Another alternative would be to create a Windows program that was compiled using the Boot Environment Application subsystem, that gives pretty raw access to the video buffer (through Bg/Bl APIs) but is largely undocumented. So you could write your whole program there and the machine would hit the BIOS then the POST, then your Boot program and as long as you keep it from exiting back to bootmgfw then your program would be the one and only!


That sounds a bit complicated, and i don't really want to make a new OS. PixelToaster is fine for my needs, and is pretty fast (is it? I'm just making 3D lines right now :) )

And while in the topic of PixelToaster, it is created using Direct3D, right? And Direct3D is hardware accelerated on most windows machines, right? So, if this is true, then that means that anything i create with PixelToaster is hardware accelerated, right?

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Original post by Phynix
And while in the topic of PixelToaster, it is created using Direct3D, right? And Direct3D is hardware accelerated on most windows machines, right? So, if this is true, then that means that anything i create with PixelToaster is hardware accelerated, right?
The presence or not of hardware acceleration in PixelToaster is really pretty meaningless when you are performing software rasterisation/ray-tracing [wink]

That said, PixelToaster is using D3D to present your surface under Windows, but even were it not, I highly doubt the blit operation could over-shadow your software rendering.

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Original post by PhynixAnd while in the topic of PixelToaster, it is created using Direct3D, right? And Direct3D is hardware accelerated on most windows machines, right? So, if this is true, then that means that anything i create with PixelToaster is hardware accelerated, right?


As pointed out, hardware acceleration these days isnt about setting single pixels or blitting, it's about transforming geometry, rasterizing, texture lookups, shader execution and parallelizing the heck out of it. What's accelerated is pretty much everything you insist on doing yourself, so basically you're walking on your hands saying "but I'm wearing running shoes, so I _should_ be pretty fast".

As a hobby project this can be fun and teaching you a lot, but don't expect your hand-rasterized triangle to be even remotely as fast as one done with D3D or OpenGL.

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      Creating Shaders
      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.
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