// ImGui Win32 + DirectX11 binding // https://github.com/ocornut/imgui #include <imgui.h> #include "imgui_impl_dx11.h" // DirectX #include <d3d11.h> #include <d3dcompiler.h> #define DIRECTINPUT_VERSION 0x0800 #include <dinput.h> // Data static INT64 g_Time = 0; static INT64 g_TicksPerSecond = 0; static HWND g_hWnd = 0; static ID3D11Device* g_pd3dDevice = NULL; static ID3D11DeviceContext* g_pd3dDeviceContext = NULL; static ID3D11Buffer* g_pVB = NULL; static ID3D10Blob * g_pVertexShaderBlob = NULL; static ID3D11VertexShader* g_pVertexShader = NULL; static ID3D11InputLayout* g_pInputLayout = NULL; static ID3D11Buffer* g_pVertexConstantBuffer = NULL; static ID3D10Blob * g_pPixelShaderBlob = NULL; static ID3D11PixelShader* g_pPixelShader = NULL; static ID3D11SamplerState* g_pFontSampler = NULL; static ID3D11ShaderResourceView*g_pFontTextureView = NULL; static ID3D11BlendState* g_blendState = NULL; static int VERTEX_BUFFER_SIZE = 30000; // TODO: Make vertex buffer smaller and grow dynamically as needed. struct VERTEX_CONSTANT_BUFFER { float mvp[4][4]; }; // This is the main rendering function that you have to implement and provide to ImGui (via setting up 'RenderDrawListsFn' in the ImGuiIO structure) // If text or lines are blurry when integrating ImGui in your engine: // - in your Render function, try translating your projection matrix by (0.5f,0.5f) or (0.375f,0.375f) static void ImGui_ImplDX11_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count) { // Copy and convert all vertices into a single contiguous buffer D3D11_MAPPED_SUBRESOURCE mappedResource; if (g_pd3dDeviceContext->Map(g_pVB, 0, D3D11_MAP_WRITE_DISCARD, 0, &mappedResource) != S_OK) return; ImDrawVert* vtx_dst = (ImDrawVert*)mappedResource.pData; for (int n = 0; n < cmd_lists_count; n++) { const ImDrawList* cmd_list = cmd_lists[n]; memcpy(vtx_dst, &cmd_list->vtx_buffer[0], cmd_list->vtx_buffer.size() * sizeof(ImDrawVert)); vtx_dst += cmd_list->vtx_buffer.size(); } g_pd3dDeviceContext->Unmap(g_pVB, 0); // Setup orthographic projection matrix into our constant buffer { D3D11_MAPPED_SUBRESOURCE mappedResource; if (g_pd3dDeviceContext->Map(g_pVertexConstantBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mappedResource) != S_OK) return; VERTEX_CONSTANT_BUFFER* pConstantBuffer = (VERTEX_CONSTANT_BUFFER*)mappedResource.pData; const float L = 0.0f; const float R = ImGui::GetIO().DisplaySize.x; const float B = ImGui::GetIO().DisplaySize.y; const float T = 0.0f; const 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(&pConstantBuffer->mvp, mvp, sizeof(mvp)); g_pd3dDeviceContext->Unmap(g_pVertexConstantBuffer, 0); } // Setup viewport { D3D11_VIEWPORT vp; memset(&vp, 0, sizeof(D3D11_VIEWPORT)); vp.Width = ImGui::GetIO().DisplaySize.x; vp.Height = ImGui::GetIO().DisplaySize.y; vp.MinDepth = 0.0f; vp.MaxDepth = 1.0f; vp.TopLeftX = 0; vp.TopLeftY = 0; g_pd3dDeviceContext->RSSetViewports(1, &vp); } // Bind shader and vertex buffers unsigned int stride = sizeof(ImDrawVert); unsigned int offset = 0; g_pd3dDeviceContext->IASetInputLayout(g_pInputLayout); g_pd3dDeviceContext->IASetVertexBuffers(0, 1, &g_pVB, &stride, &offset); g_pd3dDeviceContext->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST); g_pd3dDeviceContext->VSSetShader(g_pVertexShader, NULL, 0); g_pd3dDeviceContext->VSSetConstantBuffers(0, 1, &g_pVertexConstantBuffer); g_pd3dDeviceContext->PSSetShader(g_pPixelShader, NULL, 0); g_pd3dDeviceContext->PSSetSamplers(0, 1, &g_pFontSampler); // Setup render state const float blendFactor[4] = { 0.f, 0.f, 0.f, 0.f }; g_pd3dDeviceContext->OMSetBlendState(g_blendState, blendFactor, 0xffffffff); // Render command lists int vtx_offset = 0; for (int n = 0; n < cmd_lists_count; n++) { const ImDrawList* cmd_list = cmd_lists[n]; for (size_t cmd_i = 0; cmd_i < cmd_list->commands.size(); cmd_i++) { const ImDrawCmd* pcmd = &cmd_list->commands[cmd_i]; if (pcmd->user_callback) { pcmd->user_callback(cmd_list, pcmd); } else { const D3D11_RECT r = { (LONG)pcmd->clip_rect.x, (LONG)pcmd->clip_rect.y, (LONG)pcmd->clip_rect.z, (LONG)pcmd->clip_rect.w }; g_pd3dDeviceContext->PSSetShaderResources(0, 1, (ID3D11ShaderResourceView**)&pcmd->texture_id); g_pd3dDeviceContext->RSSetScissorRects(1, &r); g_pd3dDeviceContext->Draw(pcmd->vtx_count, vtx_offset); } vtx_offset += pcmd->vtx_count; } } // Restore modified state g_pd3dDeviceContext->IASetInputLayout(NULL); g_pd3dDeviceContext->PSSetShader(NULL, NULL, 0); g_pd3dDeviceContext->VSSetShader(NULL, NULL, 0); } LRESULT ImGui_ImplDX11_WndProcHandler(HWND, UINT msg, WPARAM wParam, LPARAM lParam) { ImGuiIO& io = ImGui::GetIO(); switch (msg) { case WM_LBUTTONDOWN: io.MouseDown[0] = true; return true; case WM_LBUTTONUP: io.MouseDown[0] = false; return true; case WM_RBUTTONDOWN: io.MouseDown[1] = true; return true; case WM_RBUTTONUP: io.MouseDown[1] = false; return true; case WM_MOUSEWHEEL: io.MouseWheel += GET_WHEEL_DELTA_WPARAM(wParam) > 0 ? +1.0f : -1.0f; return true; case WM_MOUSEMOVE: io.MousePos.x = (signed short)(lParam); io.MousePos.y = (signed short)(lParam >> 16); return true; case WM_KEYDOWN: if (wParam < 256) io.KeysDown[wParam] = 1; return true; case WM_KEYUP: if (wParam < 256) io.KeysDown[wParam] = 0; return true; case WM_CHAR: // You can also use ToAscii()+GetKeyboardState() to retrieve characters. if (wParam > 0 && wParam < 0x10000) io.AddInputCharacter((unsigned short)wParam); return true; } return 0; } static void ImGui_ImplDX11_CreateFontsTexture() { ImGuiIO& io = ImGui::GetIO(); // Build unsigned char* pixels; int width, height; io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height); // Create DX11 texture { D3D11_TEXTURE2D_DESC texDesc; ZeroMemory(&texDesc, sizeof(texDesc)); texDesc.Width = width; texDesc.Height = height; texDesc.MipLevels = 1; texDesc.ArraySize = 1; texDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM; texDesc.SampleDesc.Count = 1; texDesc.Usage = D3D11_USAGE_DEFAULT; texDesc.BindFlags = D3D11_BIND_SHADER_RESOURCE; texDesc.CPUAccessFlags = 0; ID3D11Texture2D *pTexture = NULL; D3D11_SUBRESOURCE_DATA subResource; subResource.pSysMem = pixels; subResource.SysMemPitch = texDesc.Width * 4; subResource.SysMemSlicePitch = 0; g_pd3dDevice->CreateTexture2D(&texDesc, &subResource, &pTexture); // Create texture view D3D11_SHADER_RESOURCE_VIEW_DESC srvDesc; ZeroMemory(&srvDesc, sizeof(srvDesc)); srvDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM; srvDesc.ViewDimension = D3D11_SRV_DIMENSION_TEXTURE2D; srvDesc.Texture2D.MipLevels = texDesc.MipLevels; srvDesc.Texture2D.MostDetailedMip = 0; g_pd3dDevice->CreateShaderResourceView(pTexture, &srvDesc, &g_pFontTextureView); pTexture->Release(); } // Store our identifier io.Fonts->TexID = (void *)g_pFontTextureView; // Create texture sampler { D3D11_SAMPLER_DESC samplerDesc; ZeroMemory(&samplerDesc, sizeof(samplerDesc)); samplerDesc.Filter = D3D11_FILTER_MIN_MAG_MIP_LINEAR; samplerDesc.AddressU = D3D11_TEXTURE_ADDRESS_WRAP; samplerDesc.AddressV = D3D11_TEXTURE_ADDRESS_WRAP; samplerDesc.AddressW = D3D11_TEXTURE_ADDRESS_WRAP; samplerDesc.MipLODBias = 0.f; samplerDesc.ComparisonFunc = D3D11_COMPARISON_ALWAYS; samplerDesc.MinLOD = 0.f; samplerDesc.MaxLOD = 0.f; g_pd3dDevice->CreateSamplerState(&samplerDesc, &g_pFontSampler); } } bool ImGui_ImplDX11_CreateDeviceObjects() { if (!g_pd3dDevice) return false; if (g_pVB) ImGui_ImplDX11_InvalidateDeviceObjects(); // Create the vertex shader { static const char* vertexShader = "cbuffer vertexBuffer : register(c0) \ {\ float4x4 ProjectionMatrix; \ };\ struct VS_INPUT\ {\ float2 pos : POSITION;\ float4 col : COLOR0;\ float2 uv : TEXCOORD0;\ };\ \ struct PS_INPUT\ {\ float4 pos : SV_POSITION;\ float4 col : COLOR0;\ float2 uv : TEXCOORD0;\ };\ \ PS_INPUT main(VS_INPUT input)\ {\ PS_INPUT output;\ output.pos = mul( ProjectionMatrix, float4(input.pos.xy, 0.f, 1.f));\ output.col = input.col;\ output.uv = input.uv;\ return output;\ }"; D3DCompile(vertexShader, strlen(vertexShader), NULL, NULL, NULL, "main", "vs_5_0", 0, 0, &g_pVertexShaderBlob, NULL); if (g_pVertexShaderBlob == NULL) // NB: Pass ID3D10Blob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob! return false; if (g_pd3dDevice->CreateVertexShader((DWORD*)g_pVertexShaderBlob->GetBufferPointer(), g_pVertexShaderBlob->GetBufferSize(), NULL, &g_pVertexShader) != S_OK) return false; // Create the input layout D3D11_INPUT_ELEMENT_DESC localLayout[] = { { "POSITION", 0, DXGI_FORMAT_R32G32B32A32_FLOAT, 0, (size_t)(&((ImDrawVert*)0)->pos), D3D11_INPUT_PER_VERTEX_DATA, 0 }, { "TEXCOORD", 0, DXGI_FORMAT_R32G32_FLOAT, 0, (size_t)(&((ImDrawVert*)0)->uv), D3D11_INPUT_PER_VERTEX_DATA, 0 }, { "COLOR", 0, DXGI_FORMAT_R8G8B8A8_UNORM, 0, (size_t)(&((ImDrawVert*)0)->col), D3D11_INPUT_PER_VERTEX_DATA, 0 }, }; if (g_pd3dDevice->CreateInputLayout(localLayout, 3, g_pVertexShaderBlob->GetBufferPointer(), g_pVertexShaderBlob->GetBufferSize(), &g_pInputLayout) != S_OK) return false; // Create the constant buffer { D3D11_BUFFER_DESC cbDesc; cbDesc.ByteWidth = sizeof(VERTEX_CONSTANT_BUFFER); cbDesc.Usage = D3D11_USAGE_DYNAMIC; cbDesc.BindFlags = D3D11_BIND_CONSTANT_BUFFER; cbDesc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE; cbDesc.MiscFlags = 0; g_pd3dDevice->CreateBuffer(&cbDesc, NULL, &g_pVertexConstantBuffer); } } // Create the pixel shader { static const char* pixelShader = "struct PS_INPUT\ {\ float4 pos : SV_POSITION;\ float4 col : COLOR0;\ float2 uv : TEXCOORD0;\ };\ sampler sampler0;\ Texture2D texture0;\ \ float4 main(PS_INPUT input) : SV_Target\ {\ float4 out_col = input.col * texture0.Sample(sampler0, input.uv); \ return out_col; \ }"; D3DCompile(pixelShader, strlen(pixelShader), NULL, NULL, NULL, "main", "ps_5_0", 0, 0, &g_pPixelShaderBlob, NULL); if (g_pPixelShaderBlob == NULL) // NB: Pass ID3D10Blob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob! return false; if (g_pd3dDevice->CreatePixelShader((DWORD*)g_pPixelShaderBlob->GetBufferPointer(), g_pPixelShaderBlob->GetBufferSize(), NULL, &g_pPixelShader) != S_OK) return false; } // Create the blending setup { D3D11_BLEND_DESC desc; ZeroMemory(&desc, sizeof(desc)); desc.AlphaToCoverageEnable = false; desc.RenderTarget[0].BlendEnable = true; desc.RenderTarget[0].SrcBlend = D3D11_BLEND_SRC_ALPHA; desc.RenderTarget[0].DestBlend = D3D11_BLEND_INV_SRC_ALPHA; desc.RenderTarget[0].BlendOp = D3D11_BLEND_OP_ADD; desc.RenderTarget[0].SrcBlendAlpha = D3D11_BLEND_INV_SRC_ALPHA; desc.RenderTarget[0].DestBlendAlpha = D3D11_BLEND_ZERO; desc.RenderTarget[0].BlendOpAlpha = D3D11_BLEND_OP_ADD; desc.RenderTarget[0].RenderTargetWriteMask = D3D11_COLOR_WRITE_ENABLE_ALL; g_pd3dDevice->CreateBlendState(&desc, &g_blendState); } // Create the vertex buffer { D3D11_BUFFER_DESC bufferDesc; memset(&bufferDesc, 0, sizeof(D3D11_BUFFER_DESC)); bufferDesc.Usage = D3D11_USAGE_DYNAMIC; bufferDesc.ByteWidth = VERTEX_BUFFER_SIZE * sizeof(ImDrawVert); bufferDesc.BindFlags = D3D11_BIND_VERTEX_BUFFER; bufferDesc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE; bufferDesc.MiscFlags = 0; if (g_pd3dDevice->CreateBuffer(&bufferDesc, NULL, &g_pVB) < 0) return false; } ImGui_ImplDX11_CreateFontsTexture(); return true; } void ImGui_ImplDX11_InvalidateDeviceObjects() { if (!g_pd3dDevice) return; if (g_pFontSampler) { g_pFontSampler->Release(); g_pFontSampler = NULL; } if (g_pFontTextureView) { g_pFontTextureView->Release(); ImGui::GetIO().Fonts->TexID = 0; } if (g_pVB) { g_pVB->Release(); g_pVB = NULL; } if (g_blendState) { g_blendState->Release(); g_blendState = NULL; } if (g_pPixelShader) { g_pPixelShader->Release(); g_pPixelShader = NULL; } if (g_pPixelShaderBlob) { g_pPixelShaderBlob->Release(); g_pPixelShaderBlob = NULL; } if (g_pVertexConstantBuffer) { g_pVertexConstantBuffer->Release(); g_pVertexConstantBuffer = NULL; } if (g_pInputLayout) { g_pInputLayout->Release(); g_pInputLayout = NULL; } if (g_pVertexShader) { g_pVertexShader->Release(); g_pVertexShader = NULL; } if (g_pVertexShaderBlob) { g_pVertexShaderBlob->Release(); g_pVertexShaderBlob = NULL; } } bool ImGui_ImplDX11_Init(void* hwnd, ID3D11Device* device, ID3D11DeviceContext* device_context) { g_hWnd = (HWND)hwnd; g_pd3dDevice = device; g_pd3dDeviceContext = device_context; if (!QueryPerformanceFrequency((LARGE_INTEGER *)&g_TicksPerSecond)) return false; if (!QueryPerformanceCounter((LARGE_INTEGER *)&g_Time)) return false; ImGuiIO& io = ImGui::GetIO(); io.KeyMap[ImGuiKey_Tab] = VK_TAB; // Keyboard mapping. ImGui will use those indices to peek into the io.KeyDown[] array that we will update during the application lifetime. io.KeyMap[ImGuiKey_LeftArrow] = VK_LEFT; io.KeyMap[ImGuiKey_RightArrow] = VK_RIGHT; io.KeyMap[ImGuiKey_UpArrow] = VK_UP; io.KeyMap[ImGuiKey_DownArrow] = VK_DOWN; io.KeyMap[ImGuiKey_Home] = VK_HOME; io.KeyMap[ImGuiKey_End] = VK_END; io.KeyMap[ImGuiKey_Delete] = VK_DELETE; io.KeyMap[ImGuiKey_Backspace] = VK_BACK; io.KeyMap[ImGuiKey_Enter] = VK_RETURN; io.KeyMap[ImGuiKey_Escape] = VK_ESCAPE; io.KeyMap[ImGuiKey_A] = 'A'; io.KeyMap[ImGuiKey_C] = 'C'; io.KeyMap[ImGuiKey_V] = 'V'; io.KeyMap[ImGuiKey_X] = 'X'; io.KeyMap[ImGuiKey_Y] = 'Y'; io.KeyMap[ImGuiKey_Z] = 'Z'; io.RenderDrawListsFn = ImGui_ImplDX11_RenderDrawLists; io.ImeWindowHandle = g_hWnd; return true; } void ImGui_ImplDX11_Shutdown() { ImGui_ImplDX11_InvalidateDeviceObjects(); ImGui::Shutdown(); g_pd3dDevice = NULL; g_pd3dDeviceContext = NULL; g_hWnd = (HWND)0; } void ImGui_ImplDX11_NewFrame() { if (!g_pVB) ImGui_ImplDX11_CreateDeviceObjects(); ImGuiIO& io = ImGui::GetIO(); // Setup display size (every frame to accommodate for window resizing) RECT rect; GetClientRect(g_hWnd, &rect); io.DisplaySize = ImVec2((float)(rect.right - rect.left), (float)(rect.bottom - rect.top)); // Setup time step INT64 current_time; QueryPerformanceCounter((LARGE_INTEGER *)¤t_time); io.DeltaTime = (float)(current_time - g_Time) / g_TicksPerSecond; g_Time = current_time; // Read keyboard modifiers inputs io.KeyCtrl = (GetKeyState(VK_CONTROL) & 0x8000) != 0; io.KeyShift = (GetKeyState(VK_SHIFT) & 0x8000) != 0; io.KeyAlt = (GetKeyState(VK_MENU) & 0x8000) != 0; // io.KeysDown : filled by WM_KEYDOWN/WM_KEYUP events // io.MousePos : filled by WM_MOUSEMOVE events // io.MouseDown : filled by WM_*BUTTON* events // io.MouseWheel : filled by WM_MOUSEWHEEL events // Hide OS mouse cursor if ImGui is drawing it SetCursor(io.MouseDrawCursor ? NULL : LoadCursor(NULL, IDC_ARROW)); // Start the frame ImGui::NewFrame(); }