我正在尝试使用SharpDX运行计算着色器并获取生成的纹理。
据我所知,我需要: 1. 创建一个纹理作为着色器的输出。 2. 将上述纹理设置为无序访问视图,以便可以对其进行写入。 3. 运行着色器 4. 将UAV纹理复制到分段纹理中,以便CPU可以访问它 5. 从分段纹理读取到位图
问题在于,无论我做什么,结果都是黑色的位图。我不认为问题在于Texture2D-> Bitmap转换代码,因为直接从分段纹理打印第一个像素也会得到0。
这是我的着色器代码:
据我所知,我需要: 1. 创建一个纹理作为着色器的输出。 2. 将上述纹理设置为无序访问视图,以便可以对其进行写入。 3. 运行着色器 4. 将UAV纹理复制到分段纹理中,以便CPU可以访问它 5. 从分段纹理读取到位图
问题在于,无论我做什么,结果都是黑色的位图。我不认为问题在于Texture2D-> Bitmap转换代码,因为直接从分段纹理打印第一个像素也会得到0。
这是我的着色器代码:
RWTexture2D<float4> Output : register(u0);
[numthreads(32, 32, 1)]
void main(uint3 id : SV_DispatchThreadID) {
Output[id.xy] = float4(0, 1.0, 0, 1.0);
}
利用微软DX11文档和博客,我拼凑出了这段代码以运行纹理:
public class GPUScreenColor {
private int adapterIndex = 0;
private Adapter1 gpu;
private Device device;
private ComputeShader computeShader;
private Texture2D texture;
private Texture2D stagingTexture;
private UnorderedAccessView view;
public GPUScreenColor() {
initializeDirectX();
}
private void initializeDirectX() {
using (var factory = new Factory1()) {
gpu = factory.GetAdapter1(adapterIndex);
}
device = new Device(gpu, DeviceCreationFlags.Debug, FeatureLevel.Level_11_1);
var compilationResult = ShaderBytecode.CompileFromFile("test.hlsl", "main", "cs_5_0", ShaderFlags.Debug);
computeShader = new ComputeShader(device, compilationResult.Bytecode);
texture = new Texture2D(device, new Texture2DDescription() {
BindFlags = BindFlags.UnorderedAccess | BindFlags.ShaderResource,
Format = Format.R8G8B8A8_UNorm,
Width = 1024,
Height = 1024,
OptionFlags = ResourceOptionFlags.None,
MipLevels = 1,
ArraySize = 1,
SampleDescription = { Count = 1, Quality = 0 }
});
UnorderedAccessView view = new UnorderedAccessView(device, texture, new UnorderedAccessViewDescription() {
Format = Format.R8G8B8A8_UNorm,
Dimension = UnorderedAccessViewDimension.Texture2D,
Texture2D = { MipSlice = 0 }
});
stagingTexture = new Texture2D(device, new Texture2DDescription {
CpuAccessFlags = CpuAccessFlags.Read,
BindFlags = BindFlags.None,
Format = Format.R8G8B8A8_UNorm,
Width = 1024,
Height = 1024,
OptionFlags = ResourceOptionFlags.None,
MipLevels = 1,
ArraySize = 1,
SampleDescription = { Count = 1, Quality = 0 },
Usage = ResourceUsage.Staging
});
}
public Bitmap getBitmap() {
device.ImmediateContext.ComputeShader.Set(computeShader);
device.ImmediateContext.ComputeShader.SetUnorderedAccessView(0, view);
device.ImmediateContext.Dispatch(32, 32, 1);
device.ImmediateContext.CopyResource(texture, stagingTexture);
var mapSource = device.ImmediateContext.MapSubresource(stagingTexture, 0, MapMode.Read, MapFlags.None);
Console.WriteLine(Marshal.ReadInt32(IntPtr.Add(mapSource.DataPointer, 0)));
try {
// Copy pixels from screen capture Texture to GDI bitmap
Bitmap bitmap = new Bitmap(1024, 1024, System.Drawing.Imaging.PixelFormat.Format32bppRgb);
BitmapData mapDest = bitmap.LockBits(new Rectangle(0, 0, 1024, 1024), ImageLockMode.ReadWrite, bitmap.PixelFormat);
try {
var sourcePtr = mapSource.DataPointer;
var destPtr = mapDest.Scan0;
for (int y = 0; y < 1024; y++) {
// Copy a single line
Utilities.CopyMemory(destPtr, sourcePtr, 1024 * 4);
// Advance pointers
sourcePtr = IntPtr.Add(sourcePtr, mapSource.RowPitch);
destPtr = IntPtr.Add(destPtr, mapDest.Stride);
}
return bitmap;
} finally {
bitmap.UnlockBits(mapDest);
}
} finally {
device.ImmediateContext.UnmapSubresource(stagingTexture, 0);
}
}
}
我对着色器还比较陌生,所以可能有一些显而易见的东西...