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Parks-n-Rec/libs/imgui-1.89.6/backends/imgui_impl_dx11.cpp

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basic engine
2023-06-12 20:00:53 -04:00
// dear imgui: Renderer Backend for DirectX11
// This needs to be used along with a Platform Backend (e.g. Win32)
// Implemented features:
// [X] Renderer: User texture binding. Use 'ID3D11ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
// [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
// 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.
// If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.
// Read online: https://github.com/ocornut/imgui/tree/master/docs
// 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: DirectX11: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
// 2021-02-18: DirectX11: Change blending equation to preserve alpha in output buffer.
// 2019-08-01: DirectX11: Fixed code querying the Geometry Shader state (would generally error with Debug layer enabled).
// 2019-07-21: DirectX11: Backup, clear and restore Geometry Shader is any is bound when calling ImGui_ImplDX10_RenderDrawData. Clearing Hull/Domain/Compute shaders without backup/restore.
// 2019-05-29: DirectX11: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
// 2019-04-30: DirectX11: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
// 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.
// 2018-08-01: DirectX11: Querying for IDXGIFactory instead of IDXGIFactory1 to increase compatibility.
// 2018-07-13: DirectX11: Fixed unreleased resources in Init and Shutdown functions.
// 2018-06-08: Misc: Extracted imgui_impl_dx11.cpp/.h away from the old combined DX11+Win32 example.
// 2018-06-08: DirectX11: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
// 2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplDX11_RenderDrawData() in the .h file so you can call it yourself.
// 2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
// 2016-05-07: DirectX11: Disabling depth-write.
#include "imgui.h"
#include "imgui_impl_dx11.h"
// DirectX
#include <stdio.h>
#include <d3d11.h>
#include <d3dcompiler.h>
#ifdef _MSC_VER
#pragma comment(lib, "d3dcompiler") // Automatically link with d3dcompiler.lib as we are using D3DCompile() below.
#endif
// DirectX11 data
struct ImGui_ImplDX11_Data
{
ID3D11Device* pd3dDevice;
ID3D11DeviceContext* pd3dDeviceContext;
IDXGIFactory* pFactory;
ID3D11Buffer* pVB;
ID3D11Buffer* pIB;
ID3D11VertexShader* pVertexShader;
ID3D11InputLayout* pInputLayout;
ID3D11Buffer* pVertexConstantBuffer;
ID3D11PixelShader* pPixelShader;
ID3D11SamplerState* pFontSampler;
ID3D11ShaderResourceView* pFontTextureView;
ID3D11RasterizerState* pRasterizerState;
ID3D11BlendState* pBlendState;
ID3D11DepthStencilState* pDepthStencilState;
int VertexBufferSize;
int IndexBufferSize;
ImGui_ImplDX11_Data() { memset((void*)this, 0, sizeof(*this)); VertexBufferSize = 5000; IndexBufferSize = 10000; }
};
struct VERTEX_CONSTANT_BUFFER_DX11
{
float mvp[4][4];
};
// 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_ImplDX11_Data* ImGui_ImplDX11_GetBackendData()
{
return ImGui::GetCurrentContext() ? (ImGui_ImplDX11_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
}
// Functions
static void ImGui_ImplDX11_SetupRenderState(ImDrawData* draw_data, ID3D11DeviceContext* ctx)
{
ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
// Setup viewport
D3D11_VIEWPORT vp;
memset(&vp, 0, sizeof(D3D11_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;
ctx->RSSetViewports(1, &vp);
// Setup shader and vertex buffers
unsigned int stride = sizeof(ImDrawVert);
unsigned int offset = 0;
ctx->IASetInputLayout(bd->pInputLayout);
ctx->IASetVertexBuffers(0, 1, &bd->pVB, &stride, &offset);
ctx->IASetIndexBuffer(bd->pIB, sizeof(ImDrawIdx) == 2 ? DXGI_FORMAT_R16_UINT : DXGI_FORMAT_R32_UINT, 0);
ctx->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
ctx->VSSetShader(bd->pVertexShader, nullptr, 0);
ctx->VSSetConstantBuffers(0, 1, &bd->pVertexConstantBuffer);
ctx->PSSetShader(bd->pPixelShader, nullptr, 0);
ctx->PSSetSamplers(0, 1, &bd->pFontSampler);
ctx->GSSetShader(nullptr, nullptr, 0);
ctx->HSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
ctx->DSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
ctx->CSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
// Setup blend state
const float blend_factor[4] = { 0.f, 0.f, 0.f, 0.f };
ctx->OMSetBlendState(bd->pBlendState, blend_factor, 0xffffffff);
ctx->OMSetDepthStencilState(bd->pDepthStencilState, 0);
ctx->RSSetState(bd->pRasterizerState);
}
// 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;
ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
ID3D11DeviceContext* ctx = bd->pd3dDeviceContext;
// Create and grow vertex/index buffers if needed
if (!bd->pVB || bd->VertexBufferSize < draw_data->TotalVtxCount)
{
if (bd->pVB) { bd->pVB->Release(); bd->pVB = nullptr; }
bd->VertexBufferSize = draw_data->TotalVtxCount + 5000;
D3D11_BUFFER_DESC desc;
memset(&desc, 0, sizeof(D3D11_BUFFER_DESC));
desc.Usage = D3D11_USAGE_DYNAMIC;
desc.ByteWidth = bd->VertexBufferSize * sizeof(ImDrawVert);
desc.BindFlags = D3D11_BIND_VERTEX_BUFFER;
desc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
desc.MiscFlags = 0;
if (bd->pd3dDevice->CreateBuffer(&desc, nullptr, &bd->pVB) < 0)
return;
}
if (!bd->pIB || bd->IndexBufferSize < draw_data->TotalIdxCount)
{
if (bd->pIB) { bd->pIB->Release(); bd->pIB = nullptr; }
bd->IndexBufferSize = draw_data->TotalIdxCount + 10000;
D3D11_BUFFER_DESC desc;
memset(&desc, 0, sizeof(D3D11_BUFFER_DESC));
desc.Usage = D3D11_USAGE_DYNAMIC;
desc.ByteWidth = bd->IndexBufferSize * sizeof(ImDrawIdx);
desc.BindFlags = D3D11_BIND_INDEX_BUFFER;
desc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
if (bd->pd3dDevice->CreateBuffer(&desc, nullptr, &bd->pIB) < 0)
return;
}
// Upload vertex/index data into a single contiguous GPU buffer
D3D11_MAPPED_SUBRESOURCE vtx_resource, idx_resource;
if (ctx->Map(bd->pVB, 0, D3D11_MAP_WRITE_DISCARD, 0, &vtx_resource) != S_OK)
return;
if (ctx->Map(bd->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(bd->pVB, 0);
ctx->Unmap(bd->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(bd->pVertexConstantBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mapped_resource) != S_OK)
return;
VERTEX_CONSTANT_BUFFER_DX11* constant_buffer = (VERTEX_CONSTANT_BUFFER_DX11*)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(bd->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 != 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_ImplDX11_SetupRenderState(draw_data, ctx);
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
const D3D11_RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
ctx->RSSetScissorRects(1, &r);
// Bind texture, Draw
ID3D11ShaderResourceView* texture_srv = (ID3D11ShaderResourceView*)pcmd->GetTexID();
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();
}
static void ImGui_ImplDX11_CreateFontsTexture()
{
// Build texture atlas
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
unsigned char* pixels;
int width, height;
io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
// Upload texture to graphics system
{
D3D11_TEXTURE2D_DESC desc;
ZeroMemory(&desc, sizeof(desc));
desc.Width = width;
desc.Height = height;
desc.MipLevels = 1;
desc.ArraySize = 1;
desc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
desc.SampleDesc.Count = 1;
desc.Usage = D3D11_USAGE_DEFAULT;
desc.BindFlags = D3D11_BIND_SHADER_RESOURCE;
desc.CPUAccessFlags = 0;
ID3D11Texture2D* pTexture = nullptr;
D3D11_SUBRESOURCE_DATA subResource;
subResource.pSysMem = pixels;
subResource.SysMemPitch = desc.Width * 4;
subResource.SysMemSlicePitch = 0;
bd->pd3dDevice->CreateTexture2D(&desc, &subResource, &pTexture);
IM_ASSERT(pTexture != nullptr);
// 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 = desc.MipLevels;
srvDesc.Texture2D.MostDetailedMip = 0;
bd->pd3dDevice->CreateShaderResourceView(pTexture, &srvDesc, &bd->pFontTextureView);
pTexture->Release();
}
// Store our identifier
io.Fonts->SetTexID((ImTextureID)bd->pFontTextureView);
// Create texture sampler
// (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
{
D3D11_SAMPLER_DESC desc;
ZeroMemory(&desc, sizeof(desc));
desc.Filter = D3D11_FILTER_MIN_MAG_MIP_LINEAR;
desc.AddressU = D3D11_TEXTURE_ADDRESS_WRAP;
desc.AddressV = D3D11_TEXTURE_ADDRESS_WRAP;
desc.AddressW = D3D11_TEXTURE_ADDRESS_WRAP;
desc.MipLODBias = 0.f;
desc.ComparisonFunc = D3D11_COMPARISON_ALWAYS;
desc.MinLOD = 0.f;
desc.MaxLOD = 0.f;
bd->pd3dDevice->CreateSamplerState(&desc, &bd->pFontSampler);
}
}
bool ImGui_ImplDX11_CreateDeviceObjects()
{
ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
if (!bd->pd3dDevice)
return false;
if (bd->pFontSampler)
ImGui_ImplDX11_InvalidateDeviceObjects();
// 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 DX11 sample code but remove this dependency you can:
// 1) compile once, save the compiled shader blobs into a file or source code and pass them to CreateVertexShader()/CreatePixelShader() [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.
// 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;\
}";
ID3DBlob* vertexShaderBlob;
if (FAILED(D3DCompile(vertexShader, strlen(vertexShader), nullptr, nullptr, nullptr, "main", "vs_4_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!
if (bd->pd3dDevice->CreateVertexShader(vertexShaderBlob->GetBufferPointer(), vertexShaderBlob->GetBufferSize(), nullptr, &bd->pVertexShader) != S_OK)
{
vertexShaderBlob->Release();
return false;
}
// Create the input layout
D3D11_INPUT_ELEMENT_DESC local_layout[] =
{
{ "POSITION", 0, DXGI_FORMAT_R32G32_FLOAT, 0, (UINT)IM_OFFSETOF(ImDrawVert, pos), D3D11_INPUT_PER_VERTEX_DATA, 0 },
{ "TEXCOORD", 0, DXGI_FORMAT_R32G32_FLOAT, 0, (UINT)IM_OFFSETOF(ImDrawVert, uv), D3D11_INPUT_PER_VERTEX_DATA, 0 },
{ "COLOR", 0, DXGI_FORMAT_R8G8B8A8_UNORM, 0, (UINT)IM_OFFSETOF(ImDrawVert, col), D3D11_INPUT_PER_VERTEX_DATA, 0 },
};
if (bd->pd3dDevice->CreateInputLayout(local_layout, 3, vertexShaderBlob->GetBufferPointer(), vertexShaderBlob->GetBufferSize(), &bd->pInputLayout) != S_OK)
{
vertexShaderBlob->Release();
return false;
}
vertexShaderBlob->Release();
// Create the constant buffer
{
D3D11_BUFFER_DESC desc;
desc.ByteWidth = sizeof(VERTEX_CONSTANT_BUFFER_DX11);
desc.Usage = D3D11_USAGE_DYNAMIC;
desc.BindFlags = D3D11_BIND_CONSTANT_BUFFER;
desc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
desc.MiscFlags = 0;
bd->pd3dDevice->CreateBuffer(&desc, nullptr, &bd->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; \
}";
ID3DBlob* pixelShaderBlob;
if (FAILED(D3DCompile(pixelShader, strlen(pixelShader), nullptr, nullptr, nullptr, "main", "ps_4_0", 0, 0, &pixelShaderBlob, nullptr)))
return false; // NB: Pass ID3DBlob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob!
if (bd->pd3dDevice->CreatePixelShader(pixelShaderBlob->GetBufferPointer(), pixelShaderBlob->GetBufferSize(), nullptr, &bd->pPixelShader) != S_OK)
{
pixelShaderBlob->Release();
return false;
}
pixelShaderBlob->Release();
}
// 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_ONE;
desc.RenderTarget[0].DestBlendAlpha = D3D11_BLEND_INV_SRC_ALPHA;
desc.RenderTarget[0].BlendOpAlpha = D3D11_BLEND_OP_ADD;
desc.RenderTarget[0].RenderTargetWriteMask = D3D11_COLOR_WRITE_ENABLE_ALL;
bd->pd3dDevice->CreateBlendState(&desc, &bd->pBlendState);
}
// Create the rasterizer state
{
D3D11_RASTERIZER_DESC desc;
ZeroMemory(&desc, sizeof(desc));
desc.FillMode = D3D11_FILL_SOLID;
desc.CullMode = D3D11_CULL_NONE;
desc.ScissorEnable = true;
desc.DepthClipEnable = true;
bd->pd3dDevice->CreateRasterizerState(&desc, &bd->pRasterizerState);
}
// Create depth-stencil State
{
D3D11_DEPTH_STENCIL_DESC desc;
ZeroMemory(&desc, sizeof(desc));
desc.DepthEnable = false;
desc.DepthWriteMask = D3D11_DEPTH_WRITE_MASK_ALL;
desc.DepthFunc = D3D11_COMPARISON_ALWAYS;
desc.StencilEnable = false;
desc.FrontFace.StencilFailOp = desc.FrontFace.StencilDepthFailOp = desc.FrontFace.StencilPassOp = D3D11_STENCIL_OP_KEEP;
desc.FrontFace.StencilFunc = D3D11_COMPARISON_ALWAYS;
desc.BackFace = desc.FrontFace;
bd->pd3dDevice->CreateDepthStencilState(&desc, &bd->pDepthStencilState);
}
ImGui_ImplDX11_CreateFontsTexture();
return true;
}
void ImGui_ImplDX11_InvalidateDeviceObjects()
{
ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
if (!bd->pd3dDevice)
return;
if (bd->pFontSampler) { bd->pFontSampler->Release(); bd->pFontSampler = nullptr; }
if (bd->pFontTextureView) { bd->pFontTextureView->Release(); bd->pFontTextureView = nullptr; ImGui::GetIO().Fonts->SetTexID(0); } // We copied data->pFontTextureView to io.Fonts->TexID so let's clear that as well.
if (bd->pIB) { bd->pIB->Release(); bd->pIB = nullptr; }
if (bd->pVB) { bd->pVB->Release(); bd->pVB = nullptr; }
if (bd->pBlendState) { bd->pBlendState->Release(); bd->pBlendState = nullptr; }
if (bd->pDepthStencilState) { bd->pDepthStencilState->Release(); bd->pDepthStencilState = nullptr; }
if (bd->pRasterizerState) { bd->pRasterizerState->Release(); bd->pRasterizerState = nullptr; }
if (bd->pPixelShader) { bd->pPixelShader->Release(); bd->pPixelShader = nullptr; }
if (bd->pVertexConstantBuffer) { bd->pVertexConstantBuffer->Release(); bd->pVertexConstantBuffer = nullptr; }
if (bd->pInputLayout) { bd->pInputLayout->Release(); bd->pInputLayout = nullptr; }
if (bd->pVertexShader) { bd->pVertexShader->Release(); bd->pVertexShader = nullptr; }
}
bool ImGui_ImplDX11_Init(ID3D11Device* device, ID3D11DeviceContext* device_context)
{
ImGuiIO& io = ImGui::GetIO();
IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
// Setup backend capabilities flags
ImGui_ImplDX11_Data* bd = IM_NEW(ImGui_ImplDX11_Data)();
io.BackendRendererUserData = (void*)bd;
io.BackendRendererName = "imgui_impl_dx11";
io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
// Get factory from device
IDXGIDevice* pDXGIDevice = nullptr;
IDXGIAdapter* pDXGIAdapter = nullptr;
IDXGIFactory* pFactory = nullptr;
if (device->QueryInterface(IID_PPV_ARGS(&pDXGIDevice)) == S_OK)
if (pDXGIDevice->GetParent(IID_PPV_ARGS(&pDXGIAdapter)) == S_OK)
if (pDXGIAdapter->GetParent(IID_PPV_ARGS(&pFactory)) == S_OK)
{
bd->pd3dDevice = device;
bd->pd3dDeviceContext = device_context;
bd->pFactory = pFactory;
}
if (pDXGIDevice) pDXGIDevice->Release();
if (pDXGIAdapter) pDXGIAdapter->Release();
bd->pd3dDevice->AddRef();
bd->pd3dDeviceContext->AddRef();
return true;
}
void ImGui_ImplDX11_Shutdown()
{
ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplDX11_InvalidateDeviceObjects();
if (bd->pFactory) { bd->pFactory->Release(); }
if (bd->pd3dDevice) { bd->pd3dDevice->Release(); }
if (bd->pd3dDeviceContext) { bd->pd3dDeviceContext->Release(); }
io.BackendRendererName = nullptr;
io.BackendRendererUserData = nullptr;
io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
IM_DELETE(bd);
}
void ImGui_ImplDX11_NewFrame()
{
ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplDX11_Init()?");
if (!bd->pFontSampler)
ImGui_ImplDX11_CreateDeviceObjects();
}