ext-imgui/backends/imgui_impl_dx12.cpp

763 lines
35 KiB
C++

// dear imgui: Renderer Backend for DirectX12
// This needs to be used along with a Platform Backend (e.g. Win32)
// Implemented features:
// [X] Renderer: User texture binding. Use 'D3D12_GPU_DESCRIPTOR_HANDLE' as ImTextureID. Read the FAQ about ImTextureID!
// [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
// Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
// This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
// To build this on 32-bit systems:
// - [Solution 1] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'ImTextureID=ImU64' (this is what we do in the 'example_win32_direct12/example_win32_direct12.vcxproj' project file)
// - [Solution 2] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'IMGUI_USER_CONFIG="my_imgui_config.h"' and inside 'my_imgui_config.h' add '#define ImTextureID ImU64' and as many other options as you like.
// - [Solution 3] IDE/msbuild: edit imconfig.h and add '#define ImTextureID ImU64' (prefer solution 2 to create your own config file!)
// - [Solution 4] command-line: add '/D ImTextureID=ImU64' to your cl.exe command-line (this is what we do in the example_win32_direct12/build_win32.bat file)
// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
// Learn about Dear ImGui:
// - FAQ https://dearimgui.com/faq
// - Getting Started https://dearimgui.com/getting-started
// - Documentation https://dearimgui.com/docs (same as your local docs/ folder).
// - Introduction, links and more at the top of imgui.cpp
// CHANGELOG
// (minor and older changes stripped away, please see git history for details)
// 2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
// 2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
// 2021-05-19: DirectX12: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
// 2021-02-18: DirectX12: Change blending equation to preserve alpha in output buffer.
// 2021-01-11: DirectX12: Improve Windows 7 compatibility (for D3D12On7) by loading d3d12.dll dynamically.
// 2020-09-16: DirectX12: Avoid rendering calls with zero-sized scissor rectangle since it generates a validation layer warning.
// 2020-09-08: DirectX12: Clarified support for building on 32-bit systems by redefining ImTextureID.
// 2019-10-18: DirectX12: *BREAKING CHANGE* Added extra ID3D12DescriptorHeap parameter to ImGui_ImplDX12_Init() function.
// 2019-05-29: DirectX12: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
// 2019-04-30: DirectX12: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
// 2019-03-29: Misc: Various minor tidying up.
// 2018-12-03: Misc: Added #pragma comment statement to automatically link with d3dcompiler.lib when using D3DCompile().
// 2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
// 2018-06-12: DirectX12: Moved the ID3D12GraphicsCommandList* parameter from NewFrame() to RenderDrawData().
// 2018-06-08: Misc: Extracted imgui_impl_dx12.cpp/.h away from the old combined DX12+Win32 example.
// 2018-06-08: DirectX12: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle (to ease support for future multi-viewport).
// 2018-02-22: Merged into master with all Win32 code synchronized to other examples.
#include "imgui.h"
#ifndef IMGUI_DISABLE
#include "imgui_impl_dx12.h"
// DirectX
#include <d3d12.h>
#include <dxgi1_4.h>
#include <d3dcompiler.h>
#ifdef _MSC_VER
#pragma comment(lib, "d3dcompiler") // Automatically link with d3dcompiler.lib as we are using D3DCompile() below.
#endif
// DirectX data
struct ImGui_ImplDX12_RenderBuffers;
struct ImGui_ImplDX12_Data
{
ID3D12Device* pd3dDevice;
ID3D12RootSignature* pRootSignature;
ID3D12PipelineState* pPipelineState;
DXGI_FORMAT RTVFormat;
ID3D12Resource* pFontTextureResource;
D3D12_CPU_DESCRIPTOR_HANDLE hFontSrvCpuDescHandle;
D3D12_GPU_DESCRIPTOR_HANDLE hFontSrvGpuDescHandle;
ID3D12DescriptorHeap* pd3dSrvDescHeap;
UINT numFramesInFlight;
ImGui_ImplDX12_RenderBuffers* pFrameResources;
UINT frameIndex;
ImGui_ImplDX12_Data() { memset((void*)this, 0, sizeof(*this)); frameIndex = UINT_MAX; }
};
// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
static ImGui_ImplDX12_Data* ImGui_ImplDX12_GetBackendData()
{
return ImGui::GetCurrentContext() ? (ImGui_ImplDX12_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
}
// Buffers used during the rendering of a frame
struct ImGui_ImplDX12_RenderBuffers
{
ID3D12Resource* IndexBuffer;
ID3D12Resource* VertexBuffer;
int IndexBufferSize;
int VertexBufferSize;
};
struct VERTEX_CONSTANT_BUFFER_DX12
{
float mvp[4][4];
};
// Functions
static void ImGui_ImplDX12_SetupRenderState(ImDrawData* draw_data, ID3D12GraphicsCommandList* ctx, ImGui_ImplDX12_RenderBuffers* fr)
{
ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
// 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).
VERTEX_CONSTANT_BUFFER_DX12 vertex_constant_buffer;
{
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(&vertex_constant_buffer.mvp, mvp, sizeof(mvp));
}
// Setup viewport
D3D12_VIEWPORT vp;
memset(&vp, 0, sizeof(D3D12_VIEWPORT));
vp.Width = draw_data->DisplaySize.x;
vp.Height = draw_data->DisplaySize.y;
vp.MinDepth = 0.0f;
vp.MaxDepth = 1.0f;
vp.TopLeftX = vp.TopLeftY = 0.0f;
ctx->RSSetViewports(1, &vp);
// Bind shader and vertex buffers
unsigned int stride = sizeof(ImDrawVert);
unsigned int offset = 0;
D3D12_VERTEX_BUFFER_VIEW vbv;
memset(&vbv, 0, sizeof(D3D12_VERTEX_BUFFER_VIEW));
vbv.BufferLocation = fr->VertexBuffer->GetGPUVirtualAddress() + offset;
vbv.SizeInBytes = fr->VertexBufferSize * stride;
vbv.StrideInBytes = stride;
ctx->IASetVertexBuffers(0, 1, &vbv);
D3D12_INDEX_BUFFER_VIEW ibv;
memset(&ibv, 0, sizeof(D3D12_INDEX_BUFFER_VIEW));
ibv.BufferLocation = fr->IndexBuffer->GetGPUVirtualAddress();
ibv.SizeInBytes = fr->IndexBufferSize * sizeof(ImDrawIdx);
ibv.Format = sizeof(ImDrawIdx) == 2 ? DXGI_FORMAT_R16_UINT : DXGI_FORMAT_R32_UINT;
ctx->IASetIndexBuffer(&ibv);
ctx->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
ctx->SetPipelineState(bd->pPipelineState);
ctx->SetGraphicsRootSignature(bd->pRootSignature);
ctx->SetGraphicsRoot32BitConstants(0, 16, &vertex_constant_buffer, 0);
// Setup blend factor
const float blend_factor[4] = { 0.f, 0.f, 0.f, 0.f };
ctx->OMSetBlendFactor(blend_factor);
}
template<typename T>
static inline void SafeRelease(T*& res)
{
if (res)
res->Release();
res = nullptr;
}
// Render function
void ImGui_ImplDX12_RenderDrawData(ImDrawData* draw_data, ID3D12GraphicsCommandList* ctx)
{
// Avoid rendering when minimized
if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
return;
// FIXME: I'm assuming that this only gets called once per frame!
// If not, we can't just re-allocate the IB or VB, we'll have to do a proper allocator.
ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
bd->frameIndex = bd->frameIndex + 1;
ImGui_ImplDX12_RenderBuffers* fr = &bd->pFrameResources[bd->frameIndex % bd->numFramesInFlight];
// Create and grow vertex/index buffers if needed
if (fr->VertexBuffer == nullptr || fr->VertexBufferSize < draw_data->TotalVtxCount)
{
SafeRelease(fr->VertexBuffer);
fr->VertexBufferSize = draw_data->TotalVtxCount + 5000;
D3D12_HEAP_PROPERTIES props;
memset(&props, 0, sizeof(D3D12_HEAP_PROPERTIES));
props.Type = D3D12_HEAP_TYPE_UPLOAD;
props.CPUPageProperty = D3D12_CPU_PAGE_PROPERTY_UNKNOWN;
props.MemoryPoolPreference = D3D12_MEMORY_POOL_UNKNOWN;
D3D12_RESOURCE_DESC desc;
memset(&desc, 0, sizeof(D3D12_RESOURCE_DESC));
desc.Dimension = D3D12_RESOURCE_DIMENSION_BUFFER;
desc.Width = fr->VertexBufferSize * sizeof(ImDrawVert);
desc.Height = 1;
desc.DepthOrArraySize = 1;
desc.MipLevels = 1;
desc.Format = DXGI_FORMAT_UNKNOWN;
desc.SampleDesc.Count = 1;
desc.Layout = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
desc.Flags = D3D12_RESOURCE_FLAG_NONE;
if (bd->pd3dDevice->CreateCommittedResource(&props, D3D12_HEAP_FLAG_NONE, &desc, D3D12_RESOURCE_STATE_GENERIC_READ, nullptr, IID_PPV_ARGS(&fr->VertexBuffer)) < 0)
return;
}
if (fr->IndexBuffer == nullptr || fr->IndexBufferSize < draw_data->TotalIdxCount)
{
SafeRelease(fr->IndexBuffer);
fr->IndexBufferSize = draw_data->TotalIdxCount + 10000;
D3D12_HEAP_PROPERTIES props;
memset(&props, 0, sizeof(D3D12_HEAP_PROPERTIES));
props.Type = D3D12_HEAP_TYPE_UPLOAD;
props.CPUPageProperty = D3D12_CPU_PAGE_PROPERTY_UNKNOWN;
props.MemoryPoolPreference = D3D12_MEMORY_POOL_UNKNOWN;
D3D12_RESOURCE_DESC desc;
memset(&desc, 0, sizeof(D3D12_RESOURCE_DESC));
desc.Dimension = D3D12_RESOURCE_DIMENSION_BUFFER;
desc.Width = fr->IndexBufferSize * sizeof(ImDrawIdx);
desc.Height = 1;
desc.DepthOrArraySize = 1;
desc.MipLevels = 1;
desc.Format = DXGI_FORMAT_UNKNOWN;
desc.SampleDesc.Count = 1;
desc.Layout = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
desc.Flags = D3D12_RESOURCE_FLAG_NONE;
if (bd->pd3dDevice->CreateCommittedResource(&props, D3D12_HEAP_FLAG_NONE, &desc, D3D12_RESOURCE_STATE_GENERIC_READ, nullptr, IID_PPV_ARGS(&fr->IndexBuffer)) < 0)
return;
}
// Upload vertex/index data into a single contiguous GPU buffer
void* vtx_resource, *idx_resource;
D3D12_RANGE range;
memset(&range, 0, sizeof(D3D12_RANGE));
if (fr->VertexBuffer->Map(0, &range, &vtx_resource) != S_OK)
return;
if (fr->IndexBuffer->Map(0, &range, &idx_resource) != S_OK)
return;
ImDrawVert* vtx_dst = (ImDrawVert*)vtx_resource;
ImDrawIdx* idx_dst = (ImDrawIdx*)idx_resource;
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;
}
fr->VertexBuffer->Unmap(0, &range);
fr->IndexBuffer->Unmap(0, &range);
// Setup desired DX state
ImGui_ImplDX12_SetupRenderState(draw_data, ctx, fr);
// Render command lists
// (Because we merged all buffers into a single one, we maintain our own offset into them)
int global_vtx_offset = 0;
int global_idx_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 != nullptr)
{
// 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_ImplDX12_SetupRenderState(draw_data, ctx, fr);
else
pcmd->UserCallback(cmd_list, pcmd);
}
else
{
// Project scissor/clipping rectangles into framebuffer space
ImVec2 clip_min(pcmd->ClipRect.x - clip_off.x, pcmd->ClipRect.y - clip_off.y);
ImVec2 clip_max(pcmd->ClipRect.z - clip_off.x, pcmd->ClipRect.w - clip_off.y);
if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
continue;
// Apply Scissor/clipping rectangle, Bind texture, Draw
const D3D12_RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
D3D12_GPU_DESCRIPTOR_HANDLE texture_handle = {};
texture_handle.ptr = (UINT64)pcmd->GetTexID();
ctx->SetGraphicsRootDescriptorTable(1, texture_handle);
ctx->RSSetScissorRects(1, &r);
ctx->DrawIndexedInstanced(pcmd->ElemCount, 1, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset, 0);
}
}
global_idx_offset += cmd_list->IdxBuffer.Size;
global_vtx_offset += cmd_list->VtxBuffer.Size;
}
}
static void ImGui_ImplDX12_CreateFontsTexture()
{
// Build texture atlas
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
unsigned char* pixels;
int width, height;
io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
// Upload texture to graphics system
{
D3D12_HEAP_PROPERTIES props;
memset(&props, 0, sizeof(D3D12_HEAP_PROPERTIES));
props.Type = D3D12_HEAP_TYPE_DEFAULT;
props.CPUPageProperty = D3D12_CPU_PAGE_PROPERTY_UNKNOWN;
props.MemoryPoolPreference = D3D12_MEMORY_POOL_UNKNOWN;
D3D12_RESOURCE_DESC desc;
ZeroMemory(&desc, sizeof(desc));
desc.Dimension = D3D12_RESOURCE_DIMENSION_TEXTURE2D;
desc.Alignment = 0;
desc.Width = width;
desc.Height = height;
desc.DepthOrArraySize = 1;
desc.MipLevels = 1;
desc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
desc.SampleDesc.Count = 1;
desc.SampleDesc.Quality = 0;
desc.Layout = D3D12_TEXTURE_LAYOUT_UNKNOWN;
desc.Flags = D3D12_RESOURCE_FLAG_NONE;
ID3D12Resource* pTexture = nullptr;
bd->pd3dDevice->CreateCommittedResource(&props, D3D12_HEAP_FLAG_NONE, &desc,
D3D12_RESOURCE_STATE_COPY_DEST, nullptr, IID_PPV_ARGS(&pTexture));
UINT uploadPitch = (width * 4 + D3D12_TEXTURE_DATA_PITCH_ALIGNMENT - 1u) & ~(D3D12_TEXTURE_DATA_PITCH_ALIGNMENT - 1u);
UINT uploadSize = height * uploadPitch;
desc.Dimension = D3D12_RESOURCE_DIMENSION_BUFFER;
desc.Alignment = 0;
desc.Width = uploadSize;
desc.Height = 1;
desc.DepthOrArraySize = 1;
desc.MipLevels = 1;
desc.Format = DXGI_FORMAT_UNKNOWN;
desc.SampleDesc.Count = 1;
desc.SampleDesc.Quality = 0;
desc.Layout = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
desc.Flags = D3D12_RESOURCE_FLAG_NONE;
props.Type = D3D12_HEAP_TYPE_UPLOAD;
props.CPUPageProperty = D3D12_CPU_PAGE_PROPERTY_UNKNOWN;
props.MemoryPoolPreference = D3D12_MEMORY_POOL_UNKNOWN;
ID3D12Resource* uploadBuffer = nullptr;
HRESULT hr = bd->pd3dDevice->CreateCommittedResource(&props, D3D12_HEAP_FLAG_NONE, &desc,
D3D12_RESOURCE_STATE_GENERIC_READ, nullptr, IID_PPV_ARGS(&uploadBuffer));
IM_ASSERT(SUCCEEDED(hr));
void* mapped = nullptr;
D3D12_RANGE range = { 0, uploadSize };
hr = uploadBuffer->Map(0, &range, &mapped);
IM_ASSERT(SUCCEEDED(hr));
for (int y = 0; y < height; y++)
memcpy((void*) ((uintptr_t) mapped + y * uploadPitch), pixels + y * width * 4, width * 4);
uploadBuffer->Unmap(0, &range);
D3D12_TEXTURE_COPY_LOCATION srcLocation = {};
srcLocation.pResource = uploadBuffer;
srcLocation.Type = D3D12_TEXTURE_COPY_TYPE_PLACED_FOOTPRINT;
srcLocation.PlacedFootprint.Footprint.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
srcLocation.PlacedFootprint.Footprint.Width = width;
srcLocation.PlacedFootprint.Footprint.Height = height;
srcLocation.PlacedFootprint.Footprint.Depth = 1;
srcLocation.PlacedFootprint.Footprint.RowPitch = uploadPitch;
D3D12_TEXTURE_COPY_LOCATION dstLocation = {};
dstLocation.pResource = pTexture;
dstLocation.Type = D3D12_TEXTURE_COPY_TYPE_SUBRESOURCE_INDEX;
dstLocation.SubresourceIndex = 0;
D3D12_RESOURCE_BARRIER barrier = {};
barrier.Type = D3D12_RESOURCE_BARRIER_TYPE_TRANSITION;
barrier.Flags = D3D12_RESOURCE_BARRIER_FLAG_NONE;
barrier.Transition.pResource = pTexture;
barrier.Transition.Subresource = D3D12_RESOURCE_BARRIER_ALL_SUBRESOURCES;
barrier.Transition.StateBefore = D3D12_RESOURCE_STATE_COPY_DEST;
barrier.Transition.StateAfter = D3D12_RESOURCE_STATE_PIXEL_SHADER_RESOURCE;
ID3D12Fence* fence = nullptr;
hr = bd->pd3dDevice->CreateFence(0, D3D12_FENCE_FLAG_NONE, IID_PPV_ARGS(&fence));
IM_ASSERT(SUCCEEDED(hr));
HANDLE event = CreateEvent(0, 0, 0, 0);
IM_ASSERT(event != nullptr);
D3D12_COMMAND_QUEUE_DESC queueDesc = {};
queueDesc.Type = D3D12_COMMAND_LIST_TYPE_DIRECT;
queueDesc.Flags = D3D12_COMMAND_QUEUE_FLAG_NONE;
queueDesc.NodeMask = 1;
ID3D12CommandQueue* cmdQueue = nullptr;
hr = bd->pd3dDevice->CreateCommandQueue(&queueDesc, IID_PPV_ARGS(&cmdQueue));
IM_ASSERT(SUCCEEDED(hr));
ID3D12CommandAllocator* cmdAlloc = nullptr;
hr = bd->pd3dDevice->CreateCommandAllocator(D3D12_COMMAND_LIST_TYPE_DIRECT, IID_PPV_ARGS(&cmdAlloc));
IM_ASSERT(SUCCEEDED(hr));
ID3D12GraphicsCommandList* cmdList = nullptr;
hr = bd->pd3dDevice->CreateCommandList(0, D3D12_COMMAND_LIST_TYPE_DIRECT, cmdAlloc, nullptr, IID_PPV_ARGS(&cmdList));
IM_ASSERT(SUCCEEDED(hr));
cmdList->CopyTextureRegion(&dstLocation, 0, 0, 0, &srcLocation, nullptr);
cmdList->ResourceBarrier(1, &barrier);
hr = cmdList->Close();
IM_ASSERT(SUCCEEDED(hr));
cmdQueue->ExecuteCommandLists(1, (ID3D12CommandList* const*)&cmdList);
hr = cmdQueue->Signal(fence, 1);
IM_ASSERT(SUCCEEDED(hr));
fence->SetEventOnCompletion(1, event);
WaitForSingleObject(event, INFINITE);
cmdList->Release();
cmdAlloc->Release();
cmdQueue->Release();
CloseHandle(event);
fence->Release();
uploadBuffer->Release();
// Create texture view
D3D12_SHADER_RESOURCE_VIEW_DESC srvDesc;
ZeroMemory(&srvDesc, sizeof(srvDesc));
srvDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
srvDesc.ViewDimension = D3D12_SRV_DIMENSION_TEXTURE2D;
srvDesc.Texture2D.MipLevels = desc.MipLevels;
srvDesc.Texture2D.MostDetailedMip = 0;
srvDesc.Shader4ComponentMapping = D3D12_DEFAULT_SHADER_4_COMPONENT_MAPPING;
bd->pd3dDevice->CreateShaderResourceView(pTexture, &srvDesc, bd->hFontSrvCpuDescHandle);
SafeRelease(bd->pFontTextureResource);
bd->pFontTextureResource = pTexture;
}
// Store our identifier
// READ THIS IF THE STATIC_ASSERT() TRIGGERS:
// - Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
// - This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
// [Solution 1] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'ImTextureID=ImU64' (this is what we do in the 'example_win32_direct12/example_win32_direct12.vcxproj' project file)
// [Solution 2] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'IMGUI_USER_CONFIG="my_imgui_config.h"' and inside 'my_imgui_config.h' add '#define ImTextureID ImU64' and as many other options as you like.
// [Solution 3] IDE/msbuild: edit imconfig.h and add '#define ImTextureID ImU64' (prefer solution 2 to create your own config file!)
// [Solution 4] command-line: add '/D ImTextureID=ImU64' to your cl.exe command-line (this is what we do in the example_win32_direct12/build_win32.bat file)
static_assert(sizeof(ImTextureID) >= sizeof(bd->hFontSrvGpuDescHandle.ptr), "Can't pack descriptor handle into TexID, 32-bit not supported yet.");
io.Fonts->SetTexID((ImTextureID)bd->hFontSrvGpuDescHandle.ptr);
}
bool ImGui_ImplDX12_CreateDeviceObjects()
{
ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
if (!bd || !bd->pd3dDevice)
return false;
if (bd->pPipelineState)
ImGui_ImplDX12_InvalidateDeviceObjects();
// Create the root signature
{
D3D12_DESCRIPTOR_RANGE descRange = {};
descRange.RangeType = D3D12_DESCRIPTOR_RANGE_TYPE_SRV;
descRange.NumDescriptors = 1;
descRange.BaseShaderRegister = 0;
descRange.RegisterSpace = 0;
descRange.OffsetInDescriptorsFromTableStart = 0;
D3D12_ROOT_PARAMETER param[2] = {};
param[0].ParameterType = D3D12_ROOT_PARAMETER_TYPE_32BIT_CONSTANTS;
param[0].Constants.ShaderRegister = 0;
param[0].Constants.RegisterSpace = 0;
param[0].Constants.Num32BitValues = 16;
param[0].ShaderVisibility = D3D12_SHADER_VISIBILITY_VERTEX;
param[1].ParameterType = D3D12_ROOT_PARAMETER_TYPE_DESCRIPTOR_TABLE;
param[1].DescriptorTable.NumDescriptorRanges = 1;
param[1].DescriptorTable.pDescriptorRanges = &descRange;
param[1].ShaderVisibility = D3D12_SHADER_VISIBILITY_PIXEL;
// Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling.
D3D12_STATIC_SAMPLER_DESC staticSampler = {};
staticSampler.Filter = D3D12_FILTER_MIN_MAG_MIP_LINEAR;
staticSampler.AddressU = D3D12_TEXTURE_ADDRESS_MODE_WRAP;
staticSampler.AddressV = D3D12_TEXTURE_ADDRESS_MODE_WRAP;
staticSampler.AddressW = D3D12_TEXTURE_ADDRESS_MODE_WRAP;
staticSampler.MipLODBias = 0.f;
staticSampler.MaxAnisotropy = 0;
staticSampler.ComparisonFunc = D3D12_COMPARISON_FUNC_ALWAYS;
staticSampler.BorderColor = D3D12_STATIC_BORDER_COLOR_TRANSPARENT_BLACK;
staticSampler.MinLOD = 0.f;
staticSampler.MaxLOD = 0.f;
staticSampler.ShaderRegister = 0;
staticSampler.RegisterSpace = 0;
staticSampler.ShaderVisibility = D3D12_SHADER_VISIBILITY_PIXEL;
D3D12_ROOT_SIGNATURE_DESC desc = {};
desc.NumParameters = _countof(param);
desc.pParameters = param;
desc.NumStaticSamplers = 1;
desc.pStaticSamplers = &staticSampler;
desc.Flags =
D3D12_ROOT_SIGNATURE_FLAG_ALLOW_INPUT_ASSEMBLER_INPUT_LAYOUT |
D3D12_ROOT_SIGNATURE_FLAG_DENY_HULL_SHADER_ROOT_ACCESS |
D3D12_ROOT_SIGNATURE_FLAG_DENY_DOMAIN_SHADER_ROOT_ACCESS |
D3D12_ROOT_SIGNATURE_FLAG_DENY_GEOMETRY_SHADER_ROOT_ACCESS;
// Load d3d12.dll and D3D12SerializeRootSignature() function address dynamically to facilitate using with D3D12On7.
// See if any version of d3d12.dll is already loaded in the process. If so, give preference to that.
static HINSTANCE d3d12_dll = ::GetModuleHandleA("d3d12.dll");
if (d3d12_dll == nullptr)
{
// Attempt to load d3d12.dll from local directories. This will only succeed if
// (1) the current OS is Windows 7, and
// (2) there exists a version of d3d12.dll for Windows 7 (D3D12On7) in one of the following directories.
// See https://github.com/ocornut/imgui/pull/3696 for details.
const char* localD3d12Paths[] = { ".\\d3d12.dll", ".\\d3d12on7\\d3d12.dll", ".\\12on7\\d3d12.dll" }; // A. current directory, B. used by some games, C. used in Microsoft D3D12On7 sample
for (int i = 0; i < IM_ARRAYSIZE(localD3d12Paths); i++)
if ((d3d12_dll = ::LoadLibraryA(localD3d12Paths[i])) != nullptr)
break;
// If failed, we are on Windows >= 10.
if (d3d12_dll == nullptr)
d3d12_dll = ::LoadLibraryA("d3d12.dll");
if (d3d12_dll == nullptr)
return false;
}
PFN_D3D12_SERIALIZE_ROOT_SIGNATURE D3D12SerializeRootSignatureFn = (PFN_D3D12_SERIALIZE_ROOT_SIGNATURE)::GetProcAddress(d3d12_dll, "D3D12SerializeRootSignature");
if (D3D12SerializeRootSignatureFn == nullptr)
return false;
ID3DBlob* blob = nullptr;
if (D3D12SerializeRootSignatureFn(&desc, D3D_ROOT_SIGNATURE_VERSION_1, &blob, nullptr) != S_OK)
return false;
bd->pd3dDevice->CreateRootSignature(0, blob->GetBufferPointer(), blob->GetBufferSize(), IID_PPV_ARGS(&bd->pRootSignature));
blob->Release();
}
// By using D3DCompile() from <d3dcompiler.h> / d3dcompiler.lib, we introduce a dependency to a given version of d3dcompiler_XX.dll (see D3DCOMPILER_DLL_A)
// If you would like to use this DX12 sample code but remove this dependency you can:
// 1) compile once, save the compiled shader blobs into a file or source code and assign them to psoDesc.VS/PS [preferred solution]
// 2) use code to detect any version of the DLL and grab a pointer to D3DCompile from the DLL.
// See https://github.com/ocornut/imgui/pull/638 for sources and details.
D3D12_GRAPHICS_PIPELINE_STATE_DESC psoDesc;
memset(&psoDesc, 0, sizeof(D3D12_GRAPHICS_PIPELINE_STATE_DESC));
psoDesc.NodeMask = 1;
psoDesc.PrimitiveTopologyType = D3D12_PRIMITIVE_TOPOLOGY_TYPE_TRIANGLE;
psoDesc.pRootSignature = bd->pRootSignature;
psoDesc.SampleMask = UINT_MAX;
psoDesc.NumRenderTargets = 1;
psoDesc.RTVFormats[0] = bd->RTVFormat;
psoDesc.SampleDesc.Count = 1;
psoDesc.Flags = D3D12_PIPELINE_STATE_FLAG_NONE;
ID3DBlob* vertexShaderBlob;
ID3DBlob* pixelShaderBlob;
// Create the vertex shader
{
static const char* vertexShader =
"cbuffer vertexBuffer : register(b0) \
{\
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;\
}";
if (FAILED(D3DCompile(vertexShader, strlen(vertexShader), nullptr, nullptr, nullptr, "main", "vs_5_0", 0, 0, &vertexShaderBlob, nullptr)))
return false; // NB: Pass ID3DBlob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob!
psoDesc.VS = { vertexShaderBlob->GetBufferPointer(), vertexShaderBlob->GetBufferSize() };
// Create the input layout
static D3D12_INPUT_ELEMENT_DESC local_layout[] =
{
{ "POSITION", 0, DXGI_FORMAT_R32G32_FLOAT, 0, (UINT)offsetof(ImDrawVert, pos), D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 },
{ "TEXCOORD", 0, DXGI_FORMAT_R32G32_FLOAT, 0, (UINT)offsetof(ImDrawVert, uv), D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 },
{ "COLOR", 0, DXGI_FORMAT_R8G8B8A8_UNORM, 0, (UINT)offsetof(ImDrawVert, col), D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 },
};
psoDesc.InputLayout = { local_layout, 3 };
}
// Create the pixel shader
{
static const char* pixelShader =
"struct PS_INPUT\
{\
float4 pos : SV_POSITION;\
float4 col : COLOR0;\
float2 uv : TEXCOORD0;\
};\
SamplerState sampler0 : register(s0);\
Texture2D texture0 : register(t0);\
\
float4 main(PS_INPUT input) : SV_Target\
{\
float4 out_col = input.col * texture0.Sample(sampler0, input.uv); \
return out_col; \
}";
if (FAILED(D3DCompile(pixelShader, strlen(pixelShader), nullptr, nullptr, nullptr, "main", "ps_5_0", 0, 0, &pixelShaderBlob, nullptr)))
{
vertexShaderBlob->Release();
return false; // NB: Pass ID3DBlob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob!
}
psoDesc.PS = { pixelShaderBlob->GetBufferPointer(), pixelShaderBlob->GetBufferSize() };
}
// Create the blending setup
{
D3D12_BLEND_DESC& desc = psoDesc.BlendState;
desc.AlphaToCoverageEnable = false;
desc.RenderTarget[0].BlendEnable = true;
desc.RenderTarget[0].SrcBlend = D3D12_BLEND_SRC_ALPHA;
desc.RenderTarget[0].DestBlend = D3D12_BLEND_INV_SRC_ALPHA;
desc.RenderTarget[0].BlendOp = D3D12_BLEND_OP_ADD;
desc.RenderTarget[0].SrcBlendAlpha = D3D12_BLEND_ONE;
desc.RenderTarget[0].DestBlendAlpha = D3D12_BLEND_INV_SRC_ALPHA;
desc.RenderTarget[0].BlendOpAlpha = D3D12_BLEND_OP_ADD;
desc.RenderTarget[0].RenderTargetWriteMask = D3D12_COLOR_WRITE_ENABLE_ALL;
}
// Create the rasterizer state
{
D3D12_RASTERIZER_DESC& desc = psoDesc.RasterizerState;
desc.FillMode = D3D12_FILL_MODE_SOLID;
desc.CullMode = D3D12_CULL_MODE_NONE;
desc.FrontCounterClockwise = FALSE;
desc.DepthBias = D3D12_DEFAULT_DEPTH_BIAS;
desc.DepthBiasClamp = D3D12_DEFAULT_DEPTH_BIAS_CLAMP;
desc.SlopeScaledDepthBias = D3D12_DEFAULT_SLOPE_SCALED_DEPTH_BIAS;
desc.DepthClipEnable = true;
desc.MultisampleEnable = FALSE;
desc.AntialiasedLineEnable = FALSE;
desc.ForcedSampleCount = 0;
desc.ConservativeRaster = D3D12_CONSERVATIVE_RASTERIZATION_MODE_OFF;
}
// Create depth-stencil State
{
D3D12_DEPTH_STENCIL_DESC& desc = psoDesc.DepthStencilState;
desc.DepthEnable = false;
desc.DepthWriteMask = D3D12_DEPTH_WRITE_MASK_ALL;
desc.DepthFunc = D3D12_COMPARISON_FUNC_ALWAYS;
desc.StencilEnable = false;
desc.FrontFace.StencilFailOp = desc.FrontFace.StencilDepthFailOp = desc.FrontFace.StencilPassOp = D3D12_STENCIL_OP_KEEP;
desc.FrontFace.StencilFunc = D3D12_COMPARISON_FUNC_ALWAYS;
desc.BackFace = desc.FrontFace;
}
HRESULT result_pipeline_state = bd->pd3dDevice->CreateGraphicsPipelineState(&psoDesc, IID_PPV_ARGS(&bd->pPipelineState));
vertexShaderBlob->Release();
pixelShaderBlob->Release();
if (result_pipeline_state != S_OK)
return false;
ImGui_ImplDX12_CreateFontsTexture();
return true;
}
void ImGui_ImplDX12_InvalidateDeviceObjects()
{
ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
if (!bd || !bd->pd3dDevice)
return;
ImGuiIO& io = ImGui::GetIO();
SafeRelease(bd->pRootSignature);
SafeRelease(bd->pPipelineState);
SafeRelease(bd->pFontTextureResource);
io.Fonts->SetTexID(0); // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
for (UINT i = 0; i < bd->numFramesInFlight; i++)
{
ImGui_ImplDX12_RenderBuffers* fr = &bd->pFrameResources[i];
SafeRelease(fr->IndexBuffer);
SafeRelease(fr->VertexBuffer);
}
}
bool ImGui_ImplDX12_Init(ID3D12Device* device, int num_frames_in_flight, DXGI_FORMAT rtv_format, ID3D12DescriptorHeap* cbv_srv_heap,
D3D12_CPU_DESCRIPTOR_HANDLE font_srv_cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE font_srv_gpu_desc_handle)
{
ImGuiIO& io = ImGui::GetIO();
IMGUI_CHECKVERSION();
IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
// Setup backend capabilities flags
ImGui_ImplDX12_Data* bd = IM_NEW(ImGui_ImplDX12_Data)();
io.BackendRendererUserData = (void*)bd;
io.BackendRendererName = "imgui_impl_dx12";
io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
bd->pd3dDevice = device;
bd->RTVFormat = rtv_format;
bd->hFontSrvCpuDescHandle = font_srv_cpu_desc_handle;
bd->hFontSrvGpuDescHandle = font_srv_gpu_desc_handle;
bd->pFrameResources = new ImGui_ImplDX12_RenderBuffers[num_frames_in_flight];
bd->numFramesInFlight = num_frames_in_flight;
bd->pd3dSrvDescHeap = cbv_srv_heap;
bd->frameIndex = UINT_MAX;
// Create buffers with a default size (they will later be grown as needed)
for (int i = 0; i < num_frames_in_flight; i++)
{
ImGui_ImplDX12_RenderBuffers* fr = &bd->pFrameResources[i];
fr->IndexBuffer = nullptr;
fr->VertexBuffer = nullptr;
fr->IndexBufferSize = 10000;
fr->VertexBufferSize = 5000;
}
return true;
}
void ImGui_ImplDX12_Shutdown()
{
ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
ImGuiIO& io = ImGui::GetIO();
// Clean up windows and device objects
ImGui_ImplDX12_InvalidateDeviceObjects();
delete[] bd->pFrameResources;
io.BackendRendererName = nullptr;
io.BackendRendererUserData = nullptr;
io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
IM_DELETE(bd);
}
void ImGui_ImplDX12_NewFrame()
{
ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
IM_ASSERT(bd != nullptr && "Context or backend not initialized! Did you call ImGui_ImplDX12_Init()?");
if (!bd->pPipelineState)
ImGui_ImplDX12_CreateDeviceObjects();
}
//-----------------------------------------------------------------------------
#endif // #ifndef IMGUI_DISABLE