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diff --git a/3rdparty/bgfx/examples/48-drawindirect/drawindirect.cpp b/3rdparty/bgfx/examples/48-drawindirect/drawindirect.cpp
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+/*
+ * Copyright 2022-2022 Liam Twigger. All rights reserved.
+ * License: https://github.com/bkaradzic/bgfx/blob/master/LICENSE
+ */
+
+// Draw Indirect
+// Render multiple different objects with one draw command. This example shows a minimal implementation of indirect drawing
+// Reading References:
+// https://litasa.github.io/blog/2017/09/04/OpenGL-MultiDrawIndirect-with-Individual-Textures
+// https://cpp-rendering.io/indirect-rendering/
+
+#include "common.h"
+#include "bgfx_utils.h"
+#include "imgui/imgui.h"
+
+namespace
+{
+
+struct PosColorVertex
+{
+ float m_x;
+ float m_y;
+ float m_z;
+ uint32_t m_abgr;
+
+ static void init()
+ {
+ ms_layout
+ .begin()
+ .add(bgfx::Attrib::Position, 3, bgfx::AttribType::Float)
+ .add(bgfx::Attrib::Color0, 4, bgfx::AttribType::Uint8, true)
+ .end();
+ };
+
+ static bgfx::VertexLayout ms_layout;
+};
+
+bgfx::VertexLayout PosColorVertex::ms_layout;
+
+struct ObjectInstance {
+ float m_vertexOffset;
+ float m_vertexCount;
+ float m_indexOffset;
+ float m_indexCount;
+
+ static void init()
+ {
+ ms_layout
+ .begin()
+ .add(bgfx::Attrib::TexCoord0, 4, bgfx::AttribType::Float)
+ .end();
+ };
+
+ static bgfx::VertexLayout ms_layout;
+ };
+
+bgfx::VertexLayout ObjectInstance::ms_layout;
+
+struct RenderInstance {
+ float m_mtx[16];
+ float m_color[4];
+
+ static void init()
+ {
+ ms_layout
+ .begin()
+ .add(bgfx::Attrib::TexCoord0, 4, bgfx::AttribType::Float)
+ .add(bgfx::Attrib::TexCoord1, 4, bgfx::AttribType::Float)
+ .add(bgfx::Attrib::TexCoord2, 4, bgfx::AttribType::Float)
+ .add(bgfx::Attrib::TexCoord3, 4, bgfx::AttribType::Float)
+ .add(bgfx::Attrib::Color0, 4, bgfx::AttribType::Float)
+ .end();
+ };
+
+ static bgfx::VertexLayout ms_layout;
+ };
+
+bgfx::VertexLayout RenderInstance::ms_layout;
+
+static PosColorVertex s_multiMeshVertices[12] =
+{
+ // Cube Model
+ {-1.0f, 1.0f, 1.0f, 0xff000000 },
+ { 1.0f, 1.0f, 1.0f, 0xff0000ff },
+ {-1.0f, -1.0f, 1.0f, 0xff00ff00 },
+ { 1.0f, -1.0f, 1.0f, 0xff00ffff },
+ {-1.0f, 1.0f, -1.0f, 0xffff0000 },
+ { 1.0f, 1.0f, -1.0f, 0xffff00ff },
+ {-1.0f, -1.0f, -1.0f, 0xffffff00 },
+ { 1.0f, -1.0f, -1.0f, 0xffffffff },
+
+ // Tetrahedron Model (offset = 8)
+ { 1.0f, 1.0f, 1.0f, 0xff0000ff },
+ { 1.0f, -1.0f, -1.0f, 0xff000000 },
+ {-1.0f, 1.0f, -1.0f, 0xff00ff00 },
+ {-1.0f, -1.0f, 1.0f, 0xff00ffff },
+};
+
+static const uint16_t s_multiMeshIndices[48] =
+{
+ // Cube Indicies
+ 0, 1, 2, // 0
+ 1, 3, 2,
+ 4, 6, 5, // 2
+ 5, 6, 7,
+ 0, 2, 4, // 4
+ 4, 2, 6,
+ 1, 5, 3, // 6
+ 5, 7, 3,
+ 0, 4, 1, // 8
+ 4, 5, 1,
+ 2, 3, 6, // 10
+ 6, 3, 7,
+
+ // Tetrahedron Indices (offset = 36)
+ 0, 2, 1,
+ 1, 2, 3,
+ 0, 3, 2,
+ 1, 3, 0,
+};
+
+static const uint32_t s_maxSideSize = 81;
+
+class DrawIndirect : public entry::AppI
+{
+public:
+ DrawIndirect(const char* _name, const char* _description, const char* _url)
+ : entry::AppI(_name, _description, _url)
+ {
+ }
+
+ void init(int32_t _argc, const char* const* _argv, uint32_t _width, uint32_t _height) override
+ {
+ Args args(_argc, _argv);
+
+ m_width = _width;
+ m_height = _height;
+ m_debug = BGFX_DEBUG_TEXT;
+ m_reset = BGFX_RESET_VSYNC;
+ m_sideSize = 11;
+ m_nDrawElements = s_maxSideSize*s_maxSideSize;
+ m_useIndirectCount = false;
+
+ bgfx::Init init;
+ init.type = args.m_type;
+ init.vendorId = args.m_pciId;
+ init.platformData.nwh = entry::getNativeWindowHandle(entry::kDefaultWindowHandle);
+ init.platformData.ndt = entry::getNativeDisplayHandle();
+ init.platformData.type = entry::getNativeWindowHandleType(entry::kDefaultWindowHandle);
+ init.resolution.width = m_width;
+ init.resolution.height = m_height;
+ init.resolution.reset = m_reset;
+ bgfx::init(init);
+
+ // Enable debug text.
+ bgfx::setDebug(m_debug);
+
+ // Set view 0 clear state.
+ bgfx::setViewClear(0
+ , BGFX_CLEAR_COLOR|BGFX_CLEAR_DEPTH
+ , 0x303030ff
+ , 1.0f
+ , 0
+ );
+
+ // Create vertex stream declaration.
+ PosColorVertex::init();
+ ObjectInstance::init();
+ RenderInstance::init();
+
+ // Create static vertex buffer.
+ m_vbh = bgfx::createVertexBuffer(
+ bgfx::makeRef(s_multiMeshVertices, sizeof(s_multiMeshVertices) )
+ , PosColorVertex::ms_layout
+ );
+
+ // Create static index buffer.
+ m_ibh = bgfx::createIndexBuffer(
+ bgfx::makeRef(s_multiMeshIndices, sizeof(s_multiMeshIndices) )
+ );
+
+ // Create program from shaders.
+ m_program = loadProgram("vs_instancing", "fs_instancing"); // These are reused from 05-instancing
+
+ m_indirect_program = BGFX_INVALID_HANDLE;
+ m_indirect_count_program = BGFX_INVALID_HANDLE;
+ m_indirect_buffer_handle = BGFX_INVALID_HANDLE;
+ m_indirect_count_buffer_handle = BGFX_INVALID_HANDLE;
+ m_object_list_buffer = BGFX_INVALID_HANDLE;
+
+ u_drawParams = bgfx::createUniform("u_drawParams", bgfx::UniformType::Vec4);
+
+ const bool computeSupported = !!(BGFX_CAPS_COMPUTE & bgfx::getCaps()->supported);
+ const bool indirectSupported = !!(BGFX_CAPS_DRAW_INDIRECT & bgfx::getCaps()->supported);
+ const bool instancingSupported = !!(BGFX_CAPS_INSTANCING & bgfx::getCaps()->supported);
+
+ if (computeSupported && indirectSupported && instancingSupported)
+ {
+ // Set up indirect program
+ // This is a barebones program that populates the indirect buffer handle with draw requests
+ m_indirect_program = bgfx::createProgram(loadShader("cs_drawindirect"), true);
+ m_indirect_buffer_handle = bgfx::createIndirectBuffer(m_nDrawElements);
+
+ const bool indirectCountSupported = !!(BGFX_CAPS_DRAW_INDIRECT_COUNT & bgfx::getCaps()->supported);
+ if (indirectCountSupported)
+ {
+ m_useIndirectCount = true;
+ m_indirect_count_program = bgfx::createProgram(loadShader("cs_drawindirect_count"), true);
+
+ const bgfx::Memory * mem = bgfx::alloc(sizeof(uint32_t));
+ *(uint32_t *)mem->data = 0;
+ m_indirect_count_buffer_handle = bgfx::createIndexBuffer(mem, BGFX_BUFFER_INDEX32 | BGFX_BUFFER_COMPUTE_WRITE | BGFX_BUFFER_DRAW_INDIRECT);
+ }
+
+ const bgfx::Memory * mem = bgfx::alloc(sizeof(ObjectInstance) * m_nDrawElements);
+ ObjectInstance* objs = (ObjectInstance*) mem->data;
+
+ for (uint32_t ii = 0; ii < m_nDrawElements; ++ii)
+ {
+ if (ii % 2)
+ {
+ // Tetrahedron
+ objs[ii].m_vertexOffset = 8;
+ objs[ii].m_vertexCount = 4; // m_vertexCount is unused in compute shader, its only here for completeness
+ objs[ii].m_indexOffset = 36;
+ objs[ii].m_indexCount = 12;
+ }
+ else
+ {
+ // Cube
+ objs[ii].m_vertexOffset = 0;
+ objs[ii].m_vertexCount = 8;
+ objs[ii].m_indexOffset = 0;
+ objs[ii].m_indexCount = 36;
+ }
+ }
+
+ // This is a list of objects to be rendered via the indirect program
+ m_object_list_buffer = bgfx::createVertexBuffer(mem, ObjectInstance::ms_layout, BGFX_BUFFER_COMPUTE_READ);
+
+ // This is the instance buffer used for rendering.
+ // You could instead use a dynamic instance buffer when rendering (use bgfx::allocInstanceDataBuffer in draw loop)
+ m_instance_buffer = bgfx::createDynamicVertexBuffer(m_nDrawElements, RenderInstance::ms_layout, BGFX_BUFFER_COMPUTE_WRITE);
+ }
+
+ m_timeOffset = bx::getHPCounter();
+
+ imguiCreate();
+ }
+
+ int shutdown() override
+ {
+ imguiDestroy();
+
+ // Cleanup.
+ bgfx::destroy(m_ibh);
+ bgfx::destroy(m_vbh);
+ bgfx::destroy(m_program);
+
+ if (bgfx::isValid(m_indirect_program))
+ {
+ bgfx::destroy(m_indirect_program);
+ }
+ if (bgfx::isValid(m_indirect_count_program))
+ {
+ bgfx::destroy(m_indirect_count_program);
+ }
+ if (bgfx::isValid(m_indirect_buffer_handle))
+ {
+ bgfx::destroy(m_indirect_buffer_handle);
+ }
+ if (bgfx::isValid(m_indirect_count_buffer_handle))
+ {
+ bgfx::destroy(m_indirect_count_buffer_handle);
+ }
+ if (bgfx::isValid(m_object_list_buffer))
+ {
+ bgfx::destroy(m_object_list_buffer);
+ }
+ if (bgfx::isValid(m_instance_buffer))
+ {
+ bgfx::destroy(m_instance_buffer);
+ }
+ bgfx::destroy(u_drawParams);
+
+ // Shutdown bgfx.
+ bgfx::shutdown();
+
+ return 0;
+ }
+
+ bool update() override
+ {
+ if (!entry::processEvents(m_width, m_height, m_debug, m_reset, &m_mouseState) )
+ {
+ // Get renderer capabilities info.
+ const bool computeSupported = !!(BGFX_CAPS_COMPUTE & bgfx::getCaps()->supported);
+ const bool indirectSupported = !!(BGFX_CAPS_DRAW_INDIRECT & bgfx::getCaps()->supported);
+ const bool indirectCountSupported = !!(BGFX_CAPS_DRAW_INDIRECT_COUNT & bgfx::getCaps()->supported);
+ const bool instancingSupported = !!(BGFX_CAPS_INSTANCING & bgfx::getCaps()->supported);
+
+ imguiBeginFrame(m_mouseState.m_mx
+ , m_mouseState.m_my
+ , (m_mouseState.m_buttons[entry::MouseButton::Left ] ? IMGUI_MBUT_LEFT : 0)
+ | (m_mouseState.m_buttons[entry::MouseButton::Right ] ? IMGUI_MBUT_RIGHT : 0)
+ | (m_mouseState.m_buttons[entry::MouseButton::Middle] ? IMGUI_MBUT_MIDDLE : 0)
+ , m_mouseState.m_mz
+ , uint16_t(m_width)
+ , uint16_t(m_height)
+ );
+
+ showExampleDialog(this);
+
+ ImGui::SetNextWindowPos(
+ ImVec2(m_width - m_width / 5.0f - 10.0f, 10.0f)
+ , ImGuiCond_FirstUseEver
+ );
+ ImGui::SetNextWindowSize(
+ ImVec2(m_width / 5.0f, m_height / 2.0f)
+ , ImGuiCond_FirstUseEver
+ );
+ ImGui::Begin("Settings"
+ , NULL
+ , 0
+ );
+
+ ImGui::Text("%d draw calls", bgfx::getStats()->numDraw);
+ ImGui::Text("%d objects drawn", m_sideSize*m_sideSize);
+
+ ImGui::Text("Grid Side Size:");
+ ImGui::SliderInt("##size", (int*)&m_sideSize, 1, s_maxSideSize);
+
+ ImGui::BeginDisabled(!indirectCountSupported);
+ ImGui::Checkbox("Indirect Count", &m_useIndirectCount);
+ ImGui::EndDisabled();
+ if (!indirectCountSupported && ImGui::IsItemHovered(ImGuiHoveredFlags_AllowWhenDisabled) )
+ {
+ ImGui::SetTooltip("Indirect Count is not supported by GPU.");
+ }
+
+ ImGui::End();
+
+ imguiEndFrame();
+
+
+ // Set view 0 default viewport.
+ bgfx::setViewRect(0, 0, 0, uint16_t(m_width), uint16_t(m_height) );
+
+ // This dummy draw call is here to make sure that view 0 is cleared
+ // if no other draw calls are submitted to view 0.
+ bgfx::touch(0);
+
+ const bx::Vec3 at = { 0.0f, 0.0f, 0.0f };
+ const bx::Vec3 eye = { 0.0f, 0.0f, -35.0f };
+
+ // Set view and projection matrix for view 0.
+ {
+ float view[16];
+ bx::mtxLookAt(view, eye, at);
+
+ float proj[16];
+ bx::mtxProj(proj, 60.0f, float(m_width)/float(m_height), 0.1f, 500.0f, bgfx::getCaps()->homogeneousDepth);
+ bgfx::setViewTransform(0, view, proj);
+
+ // Set view 0 default viewport.
+ bgfx::setViewRect(0, 0, 0, uint16_t(m_width), uint16_t(m_height) );
+ }
+
+ float time = (float)( (bx::getHPCounter() - m_timeOffset)/double(bx::getHPFrequency() ) );
+
+ if (computeSupported && indirectSupported && instancingSupported)
+ {
+ // Build indirect buffer & prepare instance buffer
+ // NOTE: IF you are rendering static data then
+ // this could be done once on startup and results stored
+ // This is done here for demonstration purposes
+
+ // The model matrix for each instance is also set on compute
+ // you could modify this to, eg, do frustrum culling on the GPU
+ float ud[4] = { float(m_nDrawElements), float(m_sideSize), float(time), 0 };
+ uint32_t numToDraw = (m_sideSize*m_sideSize);
+
+ bgfx::setUniform(u_drawParams, ud);
+
+ bgfx::setBuffer(0, m_object_list_buffer, bgfx::Access::Read);
+ bgfx::setBuffer(1, m_indirect_buffer_handle, bgfx::Access::Write);
+ bgfx::setBuffer(2, m_instance_buffer, bgfx::Access::Write);
+
+ // Dispatch the call. We are using 64 local threads on the GPU to process the object list
+ // So lets dispatch ceil(numToDraw/64) workgroups of 64 local threads
+ if (m_useIndirectCount)
+ {
+ bgfx::setBuffer(3, m_indirect_count_buffer_handle, bgfx::Access::Write);
+ bgfx::dispatch(0, m_indirect_count_program, uint32_t(numToDraw/64 + 1), 1, 1);
+ }
+ else
+ {
+ bgfx::dispatch(0, m_indirect_program, uint32_t(numToDraw/64 + 1), 1, 1);
+ }
+
+ // Submit our 1 draw call
+ // Set vertex and index buffer.
+ bgfx::setIndexBuffer(m_ibh);
+ bgfx::setVertexBuffer(0, m_vbh);
+ bgfx::setInstanceDataBuffer(m_instance_buffer, 0, numToDraw);
+
+ // Set render states.
+ bgfx::setState(BGFX_STATE_DEFAULT);
+
+ // Submit primitive for rendering to view 0.
+ if (m_useIndirectCount)
+ {
+ // With indirect count, the number of draws is read from a buffer
+ bgfx::submit(0, m_program, m_indirect_buffer_handle, 0, m_indirect_count_buffer_handle);
+ }
+ else
+ {
+ bgfx::submit(0, m_program, m_indirect_buffer_handle, 0, uint16_t(numToDraw));
+ }
+ }
+ else
+ {
+ // Compute/Indirect/Instancing is not supported
+ bool blink = uint32_t(time*3.0f)&1;
+ bgfx::dbgTextPrintf(0, 0, blink ? 0x4f : 0x04, " Compute/Indirect/Instancing is not supported by GPU. ");
+ }
+
+ // Advance to next frame. Rendering thread will be kicked to
+ // process submitted rendering primitives.
+ bgfx::frame();
+
+ return true;
+ }
+
+ return false;
+ }
+
+ entry::MouseState m_mouseState;
+
+ uint32_t m_width;
+ uint32_t m_height;
+ uint32_t m_debug;
+ uint32_t m_reset;
+ uint32_t m_sideSize;
+ uint32_t m_nDrawElements;
+ bool m_useIndirectCount;
+
+ bgfx::VertexBufferHandle m_vbh;
+ bgfx::IndexBufferHandle m_ibh;
+ bgfx::ProgramHandle m_program;
+ bgfx::IndirectBufferHandle m_indirect_buffer_handle;
+ bgfx::IndexBufferHandle m_indirect_count_buffer_handle;
+ bgfx::ProgramHandle m_indirect_program;
+ bgfx::ProgramHandle m_indirect_count_program;
+ bgfx::VertexBufferHandle m_object_list_buffer;
+ bgfx::DynamicVertexBufferHandle m_instance_buffer;
+ bgfx::UniformHandle u_drawParams;
+
+ int64_t m_timeOffset;
+};
+
+} // namespace
+
+ENTRY_IMPLEMENT_MAIN(
+ DrawIndirect
+ , "48-drawindirect"
+ , "Simple example of indirect rendering to render multiple different meshes with 1 draw call"
+ , "https://bkaradzic.github.io/bgfx/examples.html#drawindirect"
+ );