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CdrTomalak

DX11 Making SlimDX tutorial code compatible with old graphics hardware...

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You might have seen me post about this problem before, but basically I have just merged the SlimDX tutorial code with Ron Pentons game framework as per his C# Game Programming book.

The problem is, this won't run on my Dell Latitude D600 ([i]DXGI ERROR UNSUPPORTED)[/i], whilst is fine on my slightly old gaming rig with an Nvidia 9800GT. All it's doing is displaying a triangle.

The quesiton is, how can I alter the code to make it compatible with the ATI Radeon Mobility 9000 graphics hardware on the D600? The specificaiton for this GPU says it doesn't even officically support DirectX9!

Here's the code anyways (excuse the lack of comments - I've stripped most of them out shorten this post).

[CODE]
using System;
using System.ComponentModel;
using SlimDX;
using SlimDX.Windows;
using System.Windows.Forms;
namespace BasicWindow_1
{
public class Game : Form
{
// --------------------------------------------------------------------
// static variables
// --------------------------------------------------------------------
static string gametitle = "Test";
static int screenwidth = 640;
static int screenheight = 480;
static bool windowed = true;
static bool graphicslost = false;
static bool paused = false;
// --------------------------------------------------------------------

// --------------------------------------------------------------------
// Direct3D9 object
// --------------------------------------------------------------------
SlimDX.Direct3D9.Direct3D myD3D;
// --------------------------------------------------------------------

// --------------------------------------------------------------------
// Devices
// --------------------------------------------------------------------

SlimDX.Direct3D11.Device graphics = null;
SlimDX.DXGI.SwapChain swapChain = null;

SlimDX.D3DCompiler.ShaderSignature inputSignature = null;
SlimDX.Direct3D11.VertexShader vertexShader = null;
SlimDX.Direct3D11.PixelShader pixelShader = null;

SlimDX.Direct3D11.RenderTargetView renderTarget = null;

SlimDX.Direct3D11.DeviceContext context = null;

// KEYBOARD ...
SlimDX.DirectInput.DirectInput directInput = null;
SlimDX.DirectInput.Keyboard keyboard = null;

// MOUSE ...
SlimDX.DirectInput.Mouse mouse = null;

// SOUND ...
SlimDX.DirectSound.DirectSound sound = null;


// --------------------------------------------------------------------

// --------------------------------------------------------------------
// Vertex Object
// --------------------------------------------------------------------
SlimDX.DataStream vertices = new DataStream(12 * 3, true, true);
SlimDX.Direct3D11.Buffer vertexBuffer = null; // This is set in init geom.
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


// ********************************************************************
// Game Constructor!
public Game()
{
ClientSize = new System.Drawing.Size( screenwidth, screenheight );

Text = gametitle;

}
// ********************************************************************


// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// START: Method InitialiseGraphics
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
public void InitialiseGraphics()
{

var description = new SlimDX.DXGI.SwapChainDescription()
{
BufferCount = 2,
Usage = SlimDX.DXGI.Usage.RenderTargetOutput,
OutputHandle = this.Handle,
IsWindowed = true,
ModeDescription = new SlimDX.DXGI.ModeDescription(0, 0, new SlimDX.Rational(60, 1), SlimDX.DXGI.Format.R8G8B8A8_UNorm),
SampleDescription = new SlimDX.DXGI.SampleDescription(1, 0),
Flags = SlimDX.DXGI.SwapChainFlags.AllowModeSwitch,
SwapEffect = SlimDX.DXGI.SwapEffect.Discard
};

SlimDX.Direct3D11.Device.CreateWithSwapChain(
SlimDX.Direct3D11.DriverType.Hardware,
SlimDX.Direct3D11.DeviceCreationFlags.Debug,
description,
out graphics,
out swapChain
);

// create a view of our render target, which is the backbuffer of the swap chain we just created
using (var resource = SlimDX.Direct3D11.Resource.FromSwapChain<SlimDX.Direct3D11.Texture2D>(swapChain, 0))
renderTarget = new SlimDX.Direct3D11.RenderTargetView(graphics, resource);
// setting a viewport is required if you want to actually see anything
context = graphics.ImmediateContext;
var viewport = new SlimDX.Direct3D11.Viewport(0.0f, 0.0f, this.ClientSize.Width, this.ClientSize.Height);
context.OutputMerger.SetTargets(renderTarget);
context.Rasterizer.SetViewports(viewport);
// load and compile the vertex shader
using (var bytecode = SlimDX.D3DCompiler.ShaderBytecode.CompileFromFile("E:\\MY_AREA\\SharpDevelop_Projects\\SlimDX_StartOver\\BasicWindow_1\\BasicWindow_1\ riangle.fx", "VShader", "vs_4_0", SlimDX.D3DCompiler.ShaderFlags.None, SlimDX.D3DCompiler.EffectFlags.None))
{
inputSignature = SlimDX.D3DCompiler.ShaderSignature.GetInputSignature(bytecode);
vertexShader = new SlimDX.Direct3D11.VertexShader(graphics, bytecode);
}

// load and compile the pixel shader
using (var bytecode = SlimDX.D3DCompiler.ShaderBytecode.CompileFromFile("E:\\MY_AREA\\SharpDevelop_Projects\\SlimDX_StartOver\\BasicWindow_1\\BasicWindow_1\ riangle.fx", "PShader", "ps_4_0", SlimDX.D3DCompiler.ShaderFlags.None, SlimDX.D3DCompiler.EffectFlags.None))
pixelShader = new SlimDX.Direct3D11.PixelShader(graphics, bytecode);


// -----------------------------------------------------------------------
}
// END: Method InitialiseGraphics


// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// ***************** InitializeSound START ****************************
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// Initialize the DirectSound subsystem
public void InitialiseSound()
{
// set up a device
sound = new SlimDX.DirectSound.DirectSound();

sound.SetCooperativeLevel( this.Handle, SlimDX.DirectSound.CooperativeLevel.Normal );
}
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>


// ********************************************************************
// *************** InitializeInput START ******************************
// ********************************************************************
// Initialize the DirectInput subsystem
public void InitialiseInput()
{
// set up the keyboard
directInput = new SlimDX.DirectInput.DirectInput();
keyboard = new SlimDX.DirectInput.Keyboard(directInput);

keyboard.SetCooperativeLevel(
this,
SlimDX.DirectInput.CooperativeLevel.Background |
SlimDX.DirectInput.CooperativeLevel.Nonexclusive );
keyboard.Acquire();
// set up the mouse
mouse = new SlimDX.DirectInput.Mouse(directInput);
mouse.SetCooperativeLevel(
this,
SlimDX.DirectInput.CooperativeLevel.Background |
SlimDX.DirectInput.CooperativeLevel.Nonexclusive );
mouse.Acquire();
}
// ********************************************************************

// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// Method InitialiseGeometry
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
public void InitialiseGeometry()
{
vertices.Write(new Vector3(0.0f, 0.5f, 0.5f));
vertices.Write(new Vector3(0.5f, -0.5f, 0.5f));
vertices.Write(new Vector3(-0.5f, -0.5f, 0.5f));
vertices.Position = 0; // Rewind the position after we're done.
// create the vertex layout and buffer
var elements = new[] { new SlimDX.Direct3D11.InputElement("POSITION", 0, SlimDX.DXGI.Format.R32G32B32_Float, 0) };
var layout = new SlimDX.Direct3D11.InputLayout(graphics, inputSignature, elements);

// Once we have our vertex data in memory, we need to load it into
// a Direct3D vertex buffer, which can then be passed into the graphics pipeline.
vertexBuffer = new SlimDX.Direct3D11.Buffer(
graphics,
vertices,
12 * 3,
SlimDX.Direct3D11.ResourceUsage.Default,
SlimDX.Direct3D11.BindFlags.VertexBuffer,
SlimDX.Direct3D11.CpuAccessFlags.None,
SlimDX.Direct3D11.ResourceOptionFlags.None,
0);

// configure the Input Assembler portion of the pipeline with the vertex data
context.InputAssembler.InputLayout = layout;
context.InputAssembler.PrimitiveTopology = SlimDX.Direct3D11.PrimitiveTopology.TriangleList;
context.InputAssembler.SetVertexBuffers(0, new SlimDX.Direct3D11.VertexBufferBinding(vertexBuffer, 12, 0));
// set the shaders
context.VertexShader.Set(vertexShader);
context.PixelShader.Set(pixelShader);
}
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// START: Method RenderFrame
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
public void RenderFrame()
{
// GT 01/06/12:
// From what I can tell, the render frame method
}
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// END: Method RenderFrame
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>


// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// ************** ProcessFrame START **********************************
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// Process one iteration of the game loop
protected virtual void ProcessFrame()
{
// process the game only while it's not paused
if( !paused )
{

}
else
System.Threading.Thread.Sleep( 1 );
}
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>


// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// Render....
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
protected virtual void Render()
{
if( graphics != null )
{
context.ClearRenderTargetView(renderTarget, new SlimDX.Color4(0.5f, 0.5f, 1.0f));

// draw the triangle
context.Draw(3, 0);
swapChain.Present(0, SlimDX.DXGI.PresentFlags.None);

}
}
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>


// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// ******************** Run START *************************************
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
// Run the game
public void Run()
{
while( this.Created )
{
// Process one frame of the game
ProcessFrame();
// Render the current scene
// I.e. display graphics to the user in the game form.
Render();
// Handle all events
Application.DoEvents();
}
}
// >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>


// ********************************************************************
// **************** HANDLE WINDOWS EVENTS *****************************
// ********************************************************************
// Handle windows events
protected override void OnLostFocus( EventArgs e )
{
base.OnLostFocus( e );
Paused = true;
}
protected override void OnKeyDown( KeyEventArgs e )
{
base.OnKeyDown( e );
if( e.KeyCode == System.Windows.Forms.Keys.Escape )
{
this.Close();
}
if ( e.KeyCode == System.Windows.Forms.Keys.P )
{
Paused = !Paused;
}
}
// ********************************************************************
// ********************************************************************
// Property to pause/unpause the game, or get its pause state
public bool Paused
{
get { return paused; }
set
{
// pause the game
if( value == true && paused == false )
{
// TO DO
//
//gametimer.Pause();
paused = true;
}
// unpause the game
if( value == false && paused == true )
{
// TO DO
//
//gametimer.Unpause();
paused = false;
}
}
}
// ********************************************************************

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// START: MAIN
[STAThread]
private static void Main(string[] args)
{
Game game;

try
{
game = new Game();

// Initialise Gfx, Sound, Input, Geometry
game.InitialiseGraphics();
game.InitialiseSound();
game.InitialiseInput();

game.InitialiseGeometry();
game.Show();
game.Run();
}
catch( Exception e )
{
MessageBox.Show( "Error: " + e.Message );
}
}
// END: MAIN
}
}
[/CODE]

EDIT: I might have found something in the SlimDX tutorial. One of the parameters to the SlimDX.Direct3D11.Device.CreateWithSwapChain() method is for Feature Levels:

[i]"The third parameter to the device creation function is an array of feature levels. Feature levels provide a unified method by which Direct3D 11 can run on lower end hardware. Each feature level mandates a specific set of functionality that an adapter must expose, enabling application developers to reliably scale their applications depending on the hardware a user might have. The array allows you to specify a set of feature levels that you’d like Direct3D to try to use. It will try them in order and create a device with the first one that works. You can use the [size=2]Device[/size][size=2].GetSupportedFeatureLevel[/size] method to get the highest feature level currently supported by the primary adapter. If you don’t care to specify a set and just want to use the highest available, you can skip the parameter and use the less generic overload. Once the device has been created, you can access the [size=2]Device[/size][size=2].FeatureLevel[/size] property to see which feature level is currently active. The [url="http://msdn.microsoft.com/en-us/library/ff476148%28VS.85%29.aspx"]10Level9[/url] reference on MSDN gives in-depth details about exactly which portions of the API are available on which feature levels."[/i]

I don't actually use this in my program, but perhaps this is the key to making my program compatible with the old D600?

EDIT: I think I've concluded something, although it's not good.

On my 9800GT rig the following works fine:

[CODE]
SlimDX.Direct3D11.FeatureLevel[] featureLevels = new SlimDX.Direct3D11.FeatureLevel[] { SlimDX.Direct3D11.FeatureLevel.Level_10_0 };
SlimDX.Direct3D11.Device.CreateWithSwapChain(
SlimDX.Direct3D11.DriverType.Hardware,
SlimDX.Direct3D11.DeviceCreationFlags.Debug,
featureLevels,
description,
out graphics,
out swapChain
);
[/CODE]

But when I use FeatureLevel.Level_10_1 or above, I get DXGI ERROR UNSUPPORTED, because this card doesn't support DX11.

I dropped down to FeatureLevel.Level_9_1 on the D600 laptop, but to no avail. Apparently the GPU supports DX8.1 and Shader 1.4, where as the requirements for Level_9_1 are shader model 2.

Oh dear. Still, it was interesting finding out. Edited by CdrTomalak

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      To create a pipeline state object, define instance of PipelineStateDesc structure. The structure defines the pipeline specifics such as if the pipeline is a compute pipeline, number and format of render targets as well as depth-stencil format:
      // This is a graphics pipeline PSODesc.IsComputePipeline = false; PSODesc.GraphicsPipeline.NumRenderTargets = 1; PSODesc.GraphicsPipeline.RTVFormats[0] = TEX_FORMAT_RGBA8_UNORM_SRGB; PSODesc.GraphicsPipeline.DSVFormat = TEX_FORMAT_D32_FLOAT; The structure also defines depth-stencil, rasterizer, blend state, input layout and other parameters. For instance, rasterizer state can be defined as in the code snippet below:
      // Init rasterizer state RasterizerStateDesc &RasterizerDesc = PSODesc.GraphicsPipeline.RasterizerDesc; RasterizerDesc.FillMode = FILL_MODE_SOLID; RasterizerDesc.CullMode = CULL_MODE_NONE; RasterizerDesc.FrontCounterClockwise = True; RasterizerDesc.ScissorEnable = True; //RSDesc.MultisampleEnable = false; // do not allow msaa (fonts would be degraded) RasterizerDesc.AntialiasedLineEnable = False; When all fields are populated, call IRenderDevice::CreatePipelineState() to create the PSO:
      m_pDev->CreatePipelineState(PSODesc, &m_pPSO); Binding Shader Resources
      Shader resource binding in Diligent Engine is based on grouping variables in 3 different groups (static, mutable and dynamic). Static variables are variables that are expected to be set only once. They may not be changed once a resource is bound to the variable. Such variables are intended to hold global constants such as camera attributes or global light attributes constant buffers. They are bound directly to the shader object:
       
      PixelShader->GetShaderVariable( "g_tex2DShadowMap" )->Set( pShadowMapSRV ); Mutable and dynamic variables are bound via a new object called Shader Resource Binding (SRB), which is created by the pipeline state:
      m_pPSO->CreateShaderResourceBinding(&m_pSRB); Dynamic and mutable resources are then bound through SRB object:
      m_pSRB->GetVariable(SHADER_TYPE_VERTEX, "tex2DDiffuse")->Set(pDiffuseTexSRV); m_pSRB->GetVariable(SHADER_TYPE_VERTEX, "cbRandomAttribs")->Set(pRandomAttrsCB); The difference between mutable and dynamic resources is that mutable ones can only be set once for every instance of a shader resource binding. Dynamic resources can be set multiple times. It is important to properly set the variable type as this may affect performance. Static variables are generally most efficient, followed by mutable. Dynamic variables are most expensive from performance point of view. This post explains shader resource binding in more details.
      Setting the Pipeline State and Invoking Draw Command
      Before any draw command can be invoked, all required vertex and index buffers as well as the pipeline state should be bound to the device context:
      // Clear render target const float zero[4] = {0, 0, 0, 0}; m_pContext->ClearRenderTarget(nullptr, zero); // Set vertex and index buffers IBuffer *buffer[] = {m_pVertexBuffer}; Uint32 offsets[] = {0}; Uint32 strides[] = {sizeof(MyVertex)}; m_pContext->SetVertexBuffers(0, 1, buffer, strides, offsets, SET_VERTEX_BUFFERS_FLAG_RESET); m_pContext->SetIndexBuffer(m_pIndexBuffer, 0); m_pContext->SetPipelineState(m_pPSO); Also, all shader resources must be committed to the device context:
      m_pContext->CommitShaderResources(m_pSRB, COMMIT_SHADER_RESOURCES_FLAG_TRANSITION_RESOURCES); When all required states and resources are bound, IDeviceContext::Draw() can be used to execute draw command or IDeviceContext::DispatchCompute() can be used to execute compute command. Note that for a draw command, graphics pipeline must be bound, and for dispatch command, compute pipeline must be bound. Draw() takes DrawAttribs structure as an argument. The structure members define all attributes required to perform the command (primitive topology, number of vertices or indices, if draw call is indexed or not, if draw call is instanced or not, if draw call is indirect or not, etc.). For example:
      DrawAttribs attrs; attrs.IsIndexed = true; attrs.IndexType = VT_UINT16; attrs.NumIndices = 36; attrs.Topology = PRIMITIVE_TOPOLOGY_TRIANGLE_LIST; pContext->Draw(attrs); Build Instructions
      Please visit this page for detailed build instructions.
      Samples
      The engine contains two graphics samples that demonstrate how the API can be used.
      AntTweakBar sample demonstrates how to use AntTweakBar library to create simple user interface. It can also be thought of as Diligent Engine’s “Hello World” example.

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

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

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

       
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