Alternative way to SwapChain->Present to draw a frame on DX11 - c++

Question

I need to hook DX11 on a game to draw some rectangle.
To do it I have tried some source code but actually the only one that work in my case is ImGui:
https://github.com/ocornut/imgui
theoretically I can use it, but because in my case I need to draw only some line I like to consider other altarnative.
For this reason I have tried this example:
http://www.directxtutorial.com/Lesson.aspx?lessonid=11-4-5
that work on a test desktop project but not in my dll that hook the game.
My dll crash in this line:
pChain->Present(0, 0);
becouse I have already hook with detour this method:
HRESULT __stdcall IDXGISwapChain_Present(IDXGISwapChain* pChain, UINT SyncInterval, UINT Flags)
{
// Get device and swapchain
if (!bGraphicsInitialised)
{
// Init Direct X
if (!InitDirectXAndInput(pChain)) return fnIDXGISwapChainPresent(pChain, SyncInterval, Flags);
// Init ImGui
ImGui::CreateContext();
ImGuiIO& io = ImGui::GetIO(); (void)io;
io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
// Setup rendering and IO
ImGui_ImplWin32_Init(hWindow);
ImGui_ImplDX11_Init(pDevice, pContext);
ImGui::GetIO().ImeWindowHandle = hWindow;
// Create render target view for rendering
ID3D11Texture2D* pBackBuffer;
pChain->GetBuffer(0, __uuidof(ID3D11Texture2D), (LPVOID*)&pBackBuffer);
HRESULT hr = pDevice->CreateRenderTargetView(pBackBuffer, NULL, &pRenderTargetView);
if (FAILED(hr))
{
std::cerr << "Failed to create render target view" << std::endl;
return fnIDXGISwapChainPresent(pChain, SyncInterval, Flags);
}
pBackBuffer->Release();
bGraphicsInitialised = true;
}
LF::Log_Update("IDXGISwapChain_Present");
// Render ImGui
ImGui_ImplDX11_NewFrame();
ImGui_ImplWin32_NewFrame();
ImGui::NewFrame();
ImGui::ShowDemoWindowCustom(test);
ImGui::EndFrame();
ImGui::Render();
pContext->OMSetRenderTargets(1, &pRenderTargetView, NULL);
ImGui_ImplDX11_RenderDrawData(ImGui::GetDrawData());
return fnIDXGISwapChainPresent(pChain, SyncInterval, Flags);
}
with this code my dll (that use ImuGui) work perfectly and not need "swapChain->Present".
Here my dll without ImuGui:
HRESULT __stdcall IDXGISwapChain_Present(IDXGISwapChain* pChain, UINT SyncInterval, UINT Flags)
{
// Get device and swapchain
if (!bGraphicsInitialised)
{
// Init Direct X
if (!InitDirectXAndInput(pChain)) return fnIDXGISwapChainPresent(pChain, SyncInterval, Flags);
// Init ImGui
////ImGui::CreateContext();
////ImGuiIO& io = ImGui::GetIO(); (void)io;
////io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
////// Setup rendering and IO
////ImGui_ImplWin32_Init(hWindow);
////ImGui_ImplDX11_Init(pDevice, pContext);
////ImGui::GetIO().ImeWindowHandle = hWindow;
// set up and initialize Direct3D
InitD3D(hWindow, pDevice, pContext);
// Create render target view for rendering
ID3D11Texture2D* pBackBuffer;
pChain->GetBuffer(0, __uuidof(ID3D11Texture2D), (LPVOID*)&pBackBuffer);
HRESULT hr = pDevice->CreateRenderTargetView(pBackBuffer, NULL, &pRenderTargetView);
if (FAILED(hr))
{
std::cerr << "Failed to create render target view" << std::endl;
return fnIDXGISwapChainPresent(pChain, SyncInterval, Flags);
}
pBackBuffer->Release();
bGraphicsInitialised = true;
}
RenderFrame();
pChain->Present(0, 0);
LF::Log_Update("pChain->Present(1, 0)");
return fnIDXGISwapChainPresent(pChain, SyncInterval, Flags);
}
and here my renderframe:
// this is the function used to render a single frame
void RenderFrame(void)
{
if (VectVertices.size() < 1)
return;
// Set transparent color
float color[4] = { 0.0f, 0.0f, 0.0f, 0.0f };
// clear the back buffer
devcon->ClearRenderTargetView(backbuffer, color);
// select which vertex buffer to display
UINT stride = sizeof(VERTEX);
UINT offset = 0;
devcon->IASetVertexBuffers(0, 1, &pVBuffer, &stride, &offset);
// select which primtive type we are using
// draw the vertex buffer to the back buffer
devcon->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_LINELIST);
devcon->Draw(VectVertices.size(), 0);
// swapchain->Present(0, 0);
}
in short my code not work becouse shouldn't use swapchain->Present that is hooked.
The here the working rendering method of imuGUI:
// Render function
void ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data)
{
// Avoid rendering when minimized
if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
return;
ID3D11DeviceContext* ctx = g_pd3dDeviceContext;
// Create and grow vertex/index buffers if needed
if (!g_pVB || g_VertexBufferSize < draw_data->TotalVtxCount)
{
if (g_pVB) { g_pVB->Release(); g_pVB = NULL; }
g_VertexBufferSize = draw_data->TotalVtxCount + 5000;
D3D11_BUFFER_DESC desc;
memset(&desc, 0, sizeof(D3D11_BUFFER_DESC));
desc.Usage = D3D11_USAGE_DYNAMIC;
desc.ByteWidth = g_VertexBufferSize * sizeof(ImDrawVert);
desc.BindFlags = D3D11_BIND_VERTEX_BUFFER;
desc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
desc.MiscFlags = 0;
if (g_pd3dDevice->CreateBuffer(&desc, NULL, &g_pVB) < 0)
return;
}
if (!g_pIB || g_IndexBufferSize < draw_data->TotalIdxCount)
{
if (g_pIB) { g_pIB->Release(); g_pIB = NULL; }
g_IndexBufferSize = draw_data->TotalIdxCount + 10000;
D3D11_BUFFER_DESC desc;
memset(&desc, 0, sizeof(D3D11_BUFFER_DESC));
desc.Usage = D3D11_USAGE_DYNAMIC;
desc.ByteWidth = g_IndexBufferSize * sizeof(ImDrawIdx);
desc.BindFlags = D3D11_BIND_INDEX_BUFFER;
desc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
if (g_pd3dDevice->CreateBuffer(&desc, NULL, &g_pIB) < 0)
return;
}
// Upload vertex/index data into a single contiguous GPU buffer
D3D11_MAPPED_SUBRESOURCE vtx_resource, idx_resource;
if (ctx->Map(g_pVB, 0, D3D11_MAP_WRITE_DISCARD, 0, &vtx_resource) != S_OK)
return;
if (ctx->Map(g_pIB, 0, D3D11_MAP_WRITE_DISCARD, 0, &idx_resource) != S_OK)
return;
ImDrawVert* vtx_dst = (ImDrawVert*)vtx_resource.pData;
ImDrawIdx* idx_dst = (ImDrawIdx*)idx_resource.pData;
for (int n = 0; n < draw_data->CmdListsCount; n++)
{
const ImDrawList* cmd_list = draw_data->CmdLists[n];
memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
vtx_dst += cmd_list->VtxBuffer.Size;
idx_dst += cmd_list->IdxBuffer.Size;
}
ctx->Unmap(g_pVB, 0);
ctx->Unmap(g_pIB, 0);
// Setup orthographic projection matrix into our constant buffer
// Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps.
{
D3D11_MAPPED_SUBRESOURCE mapped_resource;
if (ctx->Map(g_pVertexConstantBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mapped_resource) != S_OK)
return;
VERTEX_CONSTANT_BUFFER* constant_buffer = (VERTEX_CONSTANT_BUFFER*)mapped_resource.pData;
float L = draw_data->DisplayPos.x;
float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x;
float T = draw_data->DisplayPos.y;
float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y;
float mvp[4][4] =
{
{ 2.0f/(R-L), 0.0f, 0.0f, 0.0f },
{ 0.0f, 2.0f/(T-B), 0.0f, 0.0f },
{ 0.0f, 0.0f, 0.5f, 0.0f },
{ (R+L)/(L-R), (T+B)/(B-T), 0.5f, 1.0f },
};
memcpy(&constant_buffer->mvp, mvp, sizeof(mvp));
ctx->Unmap(g_pVertexConstantBuffer, 0);
}
// Backup DX state that will be modified to restore it afterwards (unfortunately this is very ugly looking and verbose. Close your eyes!)
struct BACKUP_DX11_STATE
{
UINT ScissorRectsCount, ViewportsCount;
D3D11_RECT ScissorRects[D3D11_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE];
D3D11_VIEWPORT Viewports[D3D11_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE];
ID3D11RasterizerState* RS;
ID3D11BlendState* BlendState;
FLOAT BlendFactor[4];
UINT SampleMask;
UINT StencilRef;
ID3D11DepthStencilState* DepthStencilState;
ID3D11ShaderResourceView* PSShaderResource;
ID3D11SamplerState* PSSampler;
ID3D11PixelShader* PS;
ID3D11VertexShader* VS;
ID3D11GeometryShader* GS;
UINT PSInstancesCount, VSInstancesCount, GSInstancesCount;
ID3D11ClassInstance *PSInstances[256], *VSInstances[256], *GSInstances[256]; // 256 is max according to PSSetShader documentation
D3D11_PRIMITIVE_TOPOLOGY PrimitiveTopology;
ID3D11Buffer* IndexBuffer, *VertexBuffer, *VSConstantBuffer;
UINT IndexBufferOffset, VertexBufferStride, VertexBufferOffset;
DXGI_FORMAT IndexBufferFormat;
ID3D11InputLayout* InputLayout;
};
BACKUP_DX11_STATE old;
old.ScissorRectsCount = old.ViewportsCount = D3D11_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE;
ctx->RSGetScissorRects(&old.ScissorRectsCount, old.ScissorRects);
ctx->RSGetViewports(&old.ViewportsCount, old.Viewports);
ctx->RSGetState(&old.RS);
ctx->OMGetBlendState(&old.BlendState, old.BlendFactor, &old.SampleMask);
ctx->OMGetDepthStencilState(&old.DepthStencilState, &old.StencilRef);
ctx->PSGetShaderResources(0, 1, &old.PSShaderResource);
ctx->PSGetSamplers(0, 1, &old.PSSampler);
old.PSInstancesCount = old.VSInstancesCount = old.GSInstancesCount = 256;
ctx->PSGetShader(&old.PS, old.PSInstances, &old.PSInstancesCount);
ctx->VSGetShader(&old.VS, old.VSInstances, &old.VSInstancesCount);
ctx->VSGetConstantBuffers(0, 1, &old.VSConstantBuffer);
ctx->GSGetShader(&old.GS, old.GSInstances, &old.GSInstancesCount);
ctx->IAGetPrimitiveTopology(&old.PrimitiveTopology);
ctx->IAGetIndexBuffer(&old.IndexBuffer, &old.IndexBufferFormat, &old.IndexBufferOffset);
ctx->IAGetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset);
ctx->IAGetInputLayout(&old.InputLayout);
// Setup desired DX state
ImGui_ImplDX11_SetupRenderState(draw_data, ctx);
// Render command lists
// (Because we merged all buffers into a single one, we maintain our own offset into them)
int global_idx_offset = 0;
int global_vtx_offset = 0;
ImVec2 clip_off = draw_data->DisplayPos;
for (int n = 0; n < draw_data->CmdListsCount; n++)
{
const ImDrawList* cmd_list = draw_data->CmdLists[n];
for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
{
const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
if (pcmd->UserCallback != NULL)
{
// User callback, registered via ImDrawList::AddCallback()
// (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
ImGui_ImplDX11_SetupRenderState(draw_data, ctx);
else
pcmd->UserCallback(cmd_list, pcmd);
}
else
{
// Apply scissor/clipping rectangle
const D3D11_RECT r = { (LONG)(pcmd->ClipRect.x - clip_off.x), (LONG)(pcmd->ClipRect.y - clip_off.y), (LONG)(pcmd->ClipRect.z - clip_off.x), (LONG)(pcmd->ClipRect.w - clip_off.y) };
ctx->RSSetScissorRects(1, &r);
// Bind texture, Draw
ID3D11ShaderResourceView* texture_srv = (ID3D11ShaderResourceView*)pcmd->TextureId;
ctx->PSSetShaderResources(0, 1, &texture_srv);
ctx->DrawIndexed(pcmd->ElemCount, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset);
}
}
global_idx_offset += cmd_list->IdxBuffer.Size;
global_vtx_offset += cmd_list->VtxBuffer.Size;
}
// Restore modified DX state
ctx->RSSetScissorRects(old.ScissorRectsCount, old.ScissorRects);
ctx->RSSetViewports(old.ViewportsCount, old.Viewports);
ctx->RSSetState(old.RS); if (old.RS) old.RS->Release();
ctx->OMSetBlendState(old.BlendState, old.BlendFactor, old.SampleMask); if (old.BlendState) old.BlendState->Release();
ctx->OMSetDepthStencilState(old.DepthStencilState, old.StencilRef); if (old.DepthStencilState) old.DepthStencilState->Release();
ctx->PSSetShaderResources(0, 1, &old.PSShaderResource); if (old.PSShaderResource) old.PSShaderResource->Release();
ctx->PSSetSamplers(0, 1, &old.PSSampler); if (old.PSSampler) old.PSSampler->Release();
ctx->PSSetShader(old.PS, old.PSInstances, old.PSInstancesCount); if (old.PS) old.PS->Release();
for (UINT i = 0; i < old.PSInstancesCount; i++) if (old.PSInstances[i]) old.PSInstances[i]->Release();
ctx->VSSetShader(old.VS, old.VSInstances, old.VSInstancesCount); if (old.VS) old.VS->Release();
ctx->VSSetConstantBuffers(0, 1, &old.VSConstantBuffer); if (old.VSConstantBuffer) old.VSConstantBuffer->Release();
ctx->GSSetShader(old.GS, old.GSInstances, old.GSInstancesCount); if (old.GS) old.GS->Release();
for (UINT i = 0; i < old.VSInstancesCount; i++) if (old.VSInstances[i]) old.VSInstances[i]->Release();
ctx->IASetPrimitiveTopology(old.PrimitiveTopology);
ctx->IASetIndexBuffer(old.IndexBuffer, old.IndexBufferFormat, old.IndexBufferOffset); if (old.IndexBuffer) old.IndexBuffer->Release();
ctx->IASetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset); if (old.VertexBuffer) old.VertexBuffer->Release();
ctx->IASetInputLayout(old.InputLayout); if (old.InputLayout) old.InputLayout->Release();
}
Can you please suggest me a way to avoid to use pChain->Present(0, 0) ?
Thank you !