c-Direct X Input Assembler-Vertex Shader链接错误

Question

我正在学习Direct X，并试图在屏幕上绘制一个基本三角形。我有一个简单的顶点着色器和像素着色器。

顶点着色器：

float4 main( float2 pos : POSITION) : SV_Position
{
return float4(pos.x,pos.y,0.0f,1.0f);
}

像素着色器：

float4 main() : SV_Target
{
return float4(1.0f,1.0f,1.0f,1.0f);
}

当运行程序时，我在输入汇编程序和顶点着色器之间得到一个链接错误：

Error: ID3D11DeviceContext::Draw: Input Assembler - Vertex Shader linkage error: Signatures between stages are incompatible. The input stage requires Semantic/Index (POSITION,0) as input, but it is not provided by the output stage.

我的渲染代码：

void renderer_draw_triangle()
{
struct vertex
{
float x;
float y;
};
const struct vertex vertices[] =
{
{0.0f, 0.5f},
{0.5f, -0.5f},
{-0.5f, -0.5f},
};
const UINT stride = sizeof(struct vertex);
const UINT offset = 0u;
ID3D11Buffer *vertex_buffer;
D3D11_BUFFER_DESC bd = {
.BindFlags = D3D11_BIND_VERTEX_BUFFER,
.Usage = D3D11_USAGE_IMMUTABLE,
.CPUAccessFlags = 0u,
.MiscFlags = 0u,
.ByteWidth = sizeof(vertices),
.StructureByteStride = stride};
D3D11_SUBRESOURCE_DATA sd = {.pSysMem = vertices};
CHECK_ERROR(device->lpVtbl->CreateBuffer(device, &bd, &sd, &vertex_buffer));
context->lpVtbl->IASetVertexBuffers(context, 0u, 1u, &vertex_buffer, &stride, &offset);
ID3D11VertexShader *vertexShader;
ID3DBlob *blob;
CHECK_DX_ERROR(D3DReadFileToBlob(L"../Engine/build/shaders/VertexShader.cso", &blob));
CHECK_DX_ERROR(device->lpVtbl->CreateVertexShader(device, blob->lpVtbl->GetBufferPointer(blob), blob->lpVtbl->GetBufferSize(blob), NULL, &vertexShader));
context->lpVtbl->VSSetShader(context, vertexShader, NULL, 0u);
ID3D11PixelShader *pixelShader;
CHECK_DX_ERROR(D3DReadFileToBlob(L"../Engine/build/shaders/PixelShader.cso", &blob));
CHECK_DX_ERROR(device->lpVtbl->CreatePixelShader(device, blob->lpVtbl->GetBufferPointer(blob), blob->lpVtbl->GetBufferSize(blob), NULL, &pixelShader));
context->lpVtbl->PSSetShader(context, pixelShader, NULL, 0u);
ID3D11InputLayout *input_layout;
const D3D11_INPUT_ELEMENT_DESC inputs[] =
{
{"POSITION", 0, DXGI_FORMAT_R32G32_FLOAT, 0, 0, D3D11_INPUT_PER_VERTEX_DATA, 0},
};
CHECK_DX_ERROR(device->lpVtbl->CreateInputLayout(device, inputs, ASIZE(inputs), blob->lpVtbl->GetBufferPointer(blob), blob->lpVtbl->GetBufferSize(blob), &input_layout));
CHECK_DX_ERROR(context->lpVtbl->IASetInputLayout(context, input_layout));
context->lpVtbl->OMSetRenderTargets(context, 1u, &target, NULL);
context->lpVtbl->IASetPrimitiveTopology(context, D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
D3D11_VIEWPORT vp = {.Width = 800, .Height = 600, .MinDepth = 0, .MaxDepth = 1, .TopLeftX = 0, .TopLeftY = 0};
context->lpVtbl->RSSetViewports(context, 1u, &vp);
CHECK_DX_ERROR(context->lpVtbl->Draw(context, ASIZE(vertices), 0u));
}

它说它在输入层找不到语义，但我已经重读了一百万次代码，不知道出了什么问题。语义显然在输入元素描述数组中。我确信输入层绑定正确。有人能帮忙吗？

Answer 1

POSITION是传统的Direct3D 9名称，SV_Position是Direct3D 10+语义。欢迎您使用，但必须保持一致。

IOW：如果在着色器中使用SV_Position(这是首选(，则需要在D3D11_INPUT_ELEMENT_DESC输入布局结构中使用SV_Position。

Answer 2

原来我必须在创建顶点着色器之前创建像素着色器。我真的不知道为什么，但它有效。

void renderer_draw_triangle()
{
struct vertex
{
float x;
float y;
};
const struct vertex vertices[] =
{
{0.0f, 0.5f},
{0.5f, -0.5f},
{-0.5f, -0.5f},
};
const UINT stride = sizeof(struct vertex);
const UINT offset = 0u;
ID3D11Buffer *vertex_buffer;
D3D11_BUFFER_DESC bd = {
.BindFlags = D3D11_BIND_VERTEX_BUFFER,
.Usage = D3D11_USAGE_IMMUTABLE,
.CPUAccessFlags = 0u,
.MiscFlags = 0u,
.ByteWidth = sizeof(vertices),
.StructureByteStride = stride};
D3D11_SUBRESOURCE_DATA sd = {.pSysMem = vertices};
CHECK_ERROR(device->lpVtbl->CreateBuffer(device, &bd, &sd, &vertex_buffer));
context->lpVtbl->IASetVertexBuffers(context, 0u, 1u, &vertex_buffer, &stride, &offset);
ID3DBlob *blob;
ID3D11PixelShader *pixelShader;
CHECK_DX_ERROR(D3DReadFileToBlob(L"../Engine/build/shaders/PixelShader.cso", &blob));
CHECK_DX_ERROR(device->lpVtbl->CreatePixelShader(device, blob->lpVtbl->GetBufferPointer(blob), blob->lpVtbl->GetBufferSize(blob), NULL, &pixelShader));

context->lpVtbl->PSSetShader(context, pixelShader, NULL, 0u);
ID3D11VertexShader *vertexShader;
CHECK_DX_ERROR(D3DReadFileToBlob(L"../Engine/build/shaders/VertexShader.cso", &blob));
CHECK_DX_ERROR(device->lpVtbl->CreateVertexShader(device, blob->lpVtbl->GetBufferPointer(blob), blob->lpVtbl->GetBufferSize(blob), NULL, &vertexShader));
context->lpVtbl->VSSetShader(context, vertexShader, NULL, 0u);
ID3D11InputLayout *input_layout;
const D3D11_INPUT_ELEMENT_DESC inputs[] =
{
{"POSITION", 0, DXGI_FORMAT_R32G32_FLOAT, 0, 0, D3D11_INPUT_PER_VERTEX_DATA, 0},
};
CHECK_DX_ERROR(device->lpVtbl->CreateInputLayout(device, inputs, ASIZE(inputs), blob->lpVtbl->GetBufferPointer(blob), blob->lpVtbl->GetBufferSize(blob), &input_layout));
CHECK_DX_ERROR(context->lpVtbl->IASetInputLayout(context, input_layout));
context->lpVtbl->OMSetRenderTargets(context, 1u, &target, NULL);
context->lpVtbl->IASetPrimitiveTopology(context, D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
D3D11_VIEWPORT vp = {.Width = 800, .Height = 600, .MinDepth = 0, .MaxDepth = 1, .TopLeftX = 0, .TopLeftY = 0};
context->lpVtbl->RSSetViewports(context, 1u, &vp);
CHECK_DX_ERROR(context->lpVtbl->Draw(context, ASIZE(vertices), 0u));
}