bgfx/examples/05-instancing/instancing.cpp
Бранимир Караџић 0df2e90edb Cleanup.
2021-04-01 20:09:16 -07:00

352 lines
8.5 KiB
C++

/*
* Copyright 2011-2021 Branimir Karadzic. All rights reserved.
* License: https://github.com/bkaradzic/bgfx#license-bsd-2-clause
*/
#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;
static PosColorVertex s_cubeVertices[8] =
{
{-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 },
};
static const uint16_t s_cubeIndices[36] =
{
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,
};
class ExampleInstancing : public entry::AppI
{
public:
ExampleInstancing(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_useInstancing = true;
m_lastFrameMissing = 0;
m_sideSize = 11;
bgfx::Init init;
init.type = args.m_type;
init.vendorId = args.m_pciId;
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();
// Create static vertex buffer.
m_vbh = bgfx::createVertexBuffer(
bgfx::makeRef(s_cubeVertices, sizeof(s_cubeVertices) )
, PosColorVertex::ms_layout
);
// Create static index buffer.
m_ibh = bgfx::createIndexBuffer(
bgfx::makeRef(s_cubeIndices, sizeof(s_cubeIndices) )
);
// Create program from shaders.
m_program = loadProgram("vs_instancing", "fs_instancing");
m_program_non_instanced = loadProgram("vs_cubes", "fs_cubes");
m_timeOffset = bx::getHPCounter();
imguiCreate();
}
int shutdown() override
{
imguiDestroy();
// Cleanup.
bgfx::destroy(m_ibh);
bgfx::destroy(m_vbh);
bgfx::destroy(m_program);
bgfx::destroy(m_program_non_instanced);
// Shutdown bgfx.
bgfx::shutdown();
return 0;
}
bool update() override
{
if (!entry::processEvents(m_width, m_height, m_debug, m_reset, &m_mouseState) )
{
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
);
// Get renderer capabilities info.
const bgfx::Caps* caps = bgfx::getCaps();
// Check if instancing is supported.
const bool instancingSupported = 0 != (BGFX_CAPS_INSTANCING & caps->supported);
m_useInstancing &= instancingSupported;
ImGui::Text("%d draw calls", bgfx::getStats()->numDraw);
ImGui::PushEnabled(instancingSupported);
ImGui::Checkbox("Use Instancing", &m_useInstancing);
ImGui::PopEnabled();
ImGui::Text("Grid Side Size:");
ImGui::SliderInt("", (int*)&m_sideSize, 1, 512);
if (m_lastFrameMissing > 0)
{
ImGui::TextColored(ImVec4(1.0f, 0.0f, 0.0f, 1.0f), "Couldn't draw %d cubes last frame", m_lastFrameMissing);
}
if (bgfx::getStats()->numDraw >= bgfx::getCaps()->limits.maxDrawCalls)
{
ImGui::TextColored(ImVec4(1.0f, 0.0f, 0.0f, 1.0f), "Draw call limit reached!");
}
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);
float time = (float)( (bx::getHPCounter() - m_timeOffset)/double(bx::getHPFrequency() ) );
if (!instancingSupported)
{
// When instancing is not supported by GPU, implement alternative
// code path that doesn't use instancing.
bool blink = uint32_t(time*3.0f)&1;
bgfx::dbgTextPrintf(0, 0, blink ? 0x4f : 0x04, " Instancing is not supported by GPU. ");
m_useInstancing = false;
}
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, 100.0f, 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) );
}
m_lastFrameMissing = 0;
if (m_useInstancing)
{
// 80 bytes stride = 64 bytes for 4x4 matrix + 16 bytes for RGBA color.
const uint16_t instanceStride = 80;
// to total number of instances to draw
uint32_t totalCubes = m_sideSize * m_sideSize;
// figure out how big of a buffer is available
uint32_t drawnCubes = bgfx::getAvailInstanceDataBuffer(totalCubes, instanceStride);
// save how many we couldn't draw due to buffer room so we can display it
m_lastFrameMissing = totalCubes - drawnCubes;
bgfx::InstanceDataBuffer idb;
bgfx::allocInstanceDataBuffer(&idb, drawnCubes, instanceStride);
uint8_t* data = idb.data;
for (uint32_t ii = 0; ii < drawnCubes; ++ii)
{
uint32_t yy = ii / m_sideSize;
uint32_t xx = ii % m_sideSize;
float* mtx = (float*)data;
bx::mtxRotateXY(mtx, time + xx * 0.21f, time + yy * 0.37f);
mtx[12] = -15.0f + float(xx) * 3.0f;
mtx[13] = -15.0f + float(yy) * 3.0f;
mtx[14] = 0.0f;
float* color = (float*)&data[64];
color[0] = bx::sin(time + float(xx) / 11.0f) * 0.5f + 0.5f;
color[1] = bx::cos(time + float(yy) / 11.0f) * 0.5f + 0.5f;
color[2] = bx::sin(time * 3.0f) * 0.5f + 0.5f;
color[3] = 1.0f;
data += instanceStride;
}
// Set vertex and index buffer.
bgfx::setVertexBuffer(0, m_vbh);
bgfx::setIndexBuffer(m_ibh);
// Set instance data buffer.
bgfx::setInstanceDataBuffer(&idb);
// Set render states.
bgfx::setState(BGFX_STATE_DEFAULT);
// Submit primitive for rendering to view 0.
bgfx::submit(0, m_program);
}
else
{
// non-instanced path
for (uint32_t yy = 0; yy < m_sideSize; ++yy)
{
for (uint32_t xx = 0; xx < m_sideSize; ++xx)
{
float mtx[16];
bx::mtxRotateXY(mtx, time + xx * 0.21f, time + yy * 0.37f);
mtx[12] = -15.0f + float(xx) * 3.0f;
mtx[13] = -15.0f + float(yy) * 3.0f;
mtx[14] = 0.0f;
// Set model matrix for rendering.
bgfx::setTransform(mtx);
// Set vertex and index buffer.
bgfx::setVertexBuffer(0, m_vbh);
bgfx::setIndexBuffer(m_ibh);
// Set render states.
bgfx::setState(BGFX_STATE_DEFAULT);
// Submit primitive for rendering to view 0.
bgfx::submit(0, m_program_non_instanced);
}
}
}
// 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;
bool m_useInstancing;
uint32_t m_lastFrameMissing;
uint32_t m_sideSize;
bgfx::VertexBufferHandle m_vbh;
bgfx::IndexBufferHandle m_ibh;
bgfx::ProgramHandle m_program;
bgfx::ProgramHandle m_program_non_instanced;
int64_t m_timeOffset;
};
} // namespace
ENTRY_IMPLEMENT_MAIN(
ExampleInstancing
, "05-instancing"
, "Geometry instancing."
, "https://bkaradzic.github.io/bgfx/examples.html#instancing"
);