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OpenGL A compiler for DirectX9 please?

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I just discovered that DirectX9 SDK has no longer support for Visual Studio 6. I already found a thread on gamedev using Google, so I don't wanna start a clash now, but I'd like to hear from few people if you would ever develop a game using a managed language such as VB.net or C#. I mean, the .net environment is clearly for managerial softwares, why should they force me to migrate towards the .net? I will never mess my pc up installing all the unrequired services, languages, frameworks and libraries that Visual Studio.net installs. Thus, my question: can you suggest me another C++ environment which is not Microsoft? I'd like it to have support for DX9, but if it doesn't, it's the same, I'll just stick to OpenGL. Just point it out if you post a reply, please :) Bill Bill Bill... If you read me - or anyone related to you does - pick your framework, roll it up, and stick it up in [censored]

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It no longer supports it, but I'm not sure if it will not work, it just might.. And also, no one is forcing you to use D3D9.0c, you can always stick with previous versions.

You can always download the free .NET2003 compiler(-only), or the .NET2005 Express Beta (something like that). Good luck!

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It doesn't work. I got many linker errors, and searching the net I learned that errors are due to the lack of support.
Tell me about this free .net compiler... How does it work? I mean, how can I do debugging, is it possible or it's just for compiling code you know it's working?

About the .net2005 beta, well, I think previous versions are buggy enough, a beta would cause my pc to explode. I still remember an error on .net 2003, the whose description was "Catastrophic error!" and nothing more... Definitely, I will never install that environment on my comp.

PS: Don't misunderstood, I generally like Microsoft, and I don't mean to start a poll to decide how much gay Bill is. I just got mad because MS is forcing me towards languages that looks more like a script to me. I don't understand why they're wasting so many efforts to get DX to work with .net scripts... Did you see the tutorials for C# in the DX SDK? It's scandalous...

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Original post by King_DuckZ
I just got mad because MS is forcing me towards languages that looks more like a script to me. Did you see the tutorials for C# in the DX SDK? It's scandalous...


From what I understand, C# has little to do with microsoft itself. C# and .Net are different in that C# is a programming language whereas .Net is actually a framework that Microsoft developed that changes the way windows sets kernel-mode permissions and system calls behind the scenes (the Windows API). I've heard rumors to the effect that Microsoft will be using only .Net in it's next version of Windows codename "Longhorn" and have everything running MFC and previous actually running in an emulator.

Long story short, I've been using .Net Studio 2005 Suite (the full version, thanks to my boss), DirectX and C++ all at the same time. It works wonderfully and the debugger is priceless! I'd say go for it, get the free version. Even though it's Beta it's suprisingly stable for a Microsoft product.

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Well, if you say so, I think I can try it as a last resource ;) Speaking of the .net framework, I hope what you said about Longhorn is just a rumor. I will leave Windows as soon as they leave the PE format, or as soon as they decide to bung a garbage collector in every line of code I write.

Btw thanks for the comment about .net studio 2005. If it turns out to be as good as Visual Studio 6 was, I'll be glad to install it.

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Original post by King_DuckZ
I just got mad because MS is forcing me towards languages that looks more like a script to me.


Just because they support Visual Studio .net does not mean they are moving to a scripting language. You still can use C++ with the .net environment. Not sure if that's what you meant, but they are not forcing you to use VB .net or C# .net, just the environment.

I currently have Visual Studio 6 installed at home and I can compile directx9 code just fine. Maybe you didn't set up directx correctly or didn't add some .lib files or the path to the include or lib folders? Just a thought.

- Kevin

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Quote:
Original post by King_DuckZ
I just discovered that DirectX9 SDK has no longer support for Visual Studio 6. I already found a thread on gamedev using Google, so I don't wanna start a clash now, but I'd like to hear from few people if you would ever develop a game using a managed language such as VB.net or C#.
I mean, the .net environment is clearly for managerial softwares, why should they force me to migrate towards the .net? I will never mess my pc up installing all the unrequired services, languages, frameworks and libraries that Visual Studio.net installs. Thus, my question: can you suggest me another C++ environment which is not Microsoft? I'd like it to have support for DX9, but if it doesn't, it's the same, I'll just stick to OpenGL. Just point it out if you post a reply, please :)

Bill Bill Bill... If you read me - or anyone related to you does - pick your framework, roll it up, and stick it up in [censored]


It has nothing to do with the .net framework. Visual Studio 6 is a very old programming tool that simply is phased out. They now only support the Visual studio .net programming tool. There really is not anything strange about it at all. You can pick up an older 9.0c SDK version in the MSDN archive (do it now before that too is phased out. You'll find it in the one of extras I believe) That should solve your problem. I think you must accept that this is the end of the road for VS6, and that it is time to either upgrade to a new version or change to another programming tool.

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Hmm. I wonder. If you ever used Intel C++, it installs itself in the compiler settings in the VS6 menus. If you knew how that worked, I can imagine you could write a plugin to use VS 2003 C++ compiler (free one) with the VS6 editor. You just click on the compiler and than everything will now compile with the new VS 2003 compiler. But does the VS 2003 compiler have a debugger you could plugin to VS6?



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You seem to be pretty confused about what Visual Studio .NET is. It's not just for .NET / managed code or for VB.NET and C#. The native C++ compiler in Visual Studio 2003 is much better than the one in VS6 - more standards compliant and much better at optimizing code as well as fully supporting newer instruction sets like SSE 1/2/3. The debugger is also improved as is the STL implementation that ships with the compiler. You can get the VS.NET 2003 native C++ compiler (the full optimizing version you get with the Professional version of Visual Studio) and libraries as a free download from MS. You only pay for the IDE and debugger. The VS.NET 2005 compiler has further improvements as does the IDE and as others have said you can get the beta for free and it's pretty stable.

I believe it's possible to use the free VS.NET 2003 C++ compiler from the VS6 IDE - a bit of Googling should turn up the details if you want to go for the free route.

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One thing, it sounds like you are under the impression that if you build a project in VS.net, that the target system will need to have .NET foundation library installed. Not true. I have my current game project being built in C++ and DX9, using VS.net. When I take it to work it runs fine, we do not have .net foundation installed here. I know this because my .NET app fails to initilize when I run it here.

Just wanted to let you know that, just because the compiler supports .NET does not mean that your project will ever link to it (ie. require it).

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Guys, thanks everyone for your answers. Frankly, I never used the Intel compiler, so I didn't know such compilers worked as plugins. Also, knowing that VS.net supports ANSI C++ is a relief. At the moment, someone suggested me to try CodeWarrior. I will give a look at it, if I'm not satisfied I will try the VS.net 2003 compiler with VS6 and the VS.net 2005 beta. I'm going to download both them now, just to make sure I don't lose or forget them, as well as the Febryary DX SDK, and I already got the October release of the SDK, so in the worst of the cases, I can keep using VS6 with a not too much outdated SDK, for now... :P Thanks again everyone ^^

uckevin111: I feel forced to use scripting languages because when I install VS.net, I also install languages I don't want. I don't know if I can exclude the .net framework and C#/VB.net editors at install time, but for what I remember, VS.net installs all his folks: VJ++, VisualFoxPro, C#, VB.net...

edit: I just realized that the J++ is now called J#. Well, that's what I meant everytime I typed J++, I forget it has his name changed on vs.net, too.

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uckevin111: I feel forced to use scripting languages because when I install VS.net, I also install languages I don't want.


During the install, instead of clicking on typical installation, choose custom installation. Then you can choose which ones you want to install, such as C++, VB, J#, etc.

Also, as far as I am aware, VB, J#, C# are not scripting languages. VBscript is a scripting language, but VB is a full language just like C++.

- Kevin

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Guest Anonymous Poster
You can use Dev-C++, it has directx 9 libraries and is 100% non-Micro$oft

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uckevin111: I figured out there was such a possibility, though I think framework is compulsory. Oh, I call those languages "script" because of my contempt. I know they are half-compiled... It would be the same as "lame language".

Anonymous Poster: is it from Borland? You'r post, for how short, it's the most interesting :p

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No it's from Bloodshed software.

Just watch the libraries...there was always that "gotcha" when porting the DX libs over to the Borland library format, and I think there's even more of them when porting them over to GCC format.

AFAIK they DO have a DX9 package for DevC++, but I'm not sure what version it is..

IMHO it's still far safer to use an MS IDE to compile DX code. Too many instantly bash MS because it's MS. Not a good enough reason to me.

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      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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