bgfx/examples/03-raymarch/raymarch.cpp
2019-08-17 12:32:16 -07:00

273 lines
6.3 KiB
C++

/*
* Copyright 2011-2019 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 PosColorTexCoord0Vertex
{
float m_x;
float m_y;
float m_z;
uint32_t m_abgr;
float m_u;
float m_v;
static void init()
{
ms_layout
.begin()
.add(bgfx::Attrib::Position, 3, bgfx::AttribType::Float)
.add(bgfx::Attrib::Color0, 4, bgfx::AttribType::Uint8, true)
.add(bgfx::Attrib::TexCoord0, 2, bgfx::AttribType::Float)
.end();
}
static bgfx::VertexLayout ms_layout;
};
bgfx::VertexLayout PosColorTexCoord0Vertex::ms_layout;
void renderScreenSpaceQuad(uint8_t _view, bgfx::ProgramHandle _program, float _x, float _y, float _width, float _height)
{
bgfx::TransientVertexBuffer tvb;
bgfx::TransientIndexBuffer tib;
if (bgfx::allocTransientBuffers(&tvb, PosColorTexCoord0Vertex::ms_layout, 4, &tib, 6) )
{
PosColorTexCoord0Vertex* vertex = (PosColorTexCoord0Vertex*)tvb.data;
float zz = 0.0f;
const float minx = _x;
const float maxx = _x + _width;
const float miny = _y;
const float maxy = _y + _height;
float minu = -1.0f;
float minv = -1.0f;
float maxu = 1.0f;
float maxv = 1.0f;
vertex[0].m_x = minx;
vertex[0].m_y = miny;
vertex[0].m_z = zz;
vertex[0].m_abgr = 0xff0000ff;
vertex[0].m_u = minu;
vertex[0].m_v = minv;
vertex[1].m_x = maxx;
vertex[1].m_y = miny;
vertex[1].m_z = zz;
vertex[1].m_abgr = 0xff00ff00;
vertex[1].m_u = maxu;
vertex[1].m_v = minv;
vertex[2].m_x = maxx;
vertex[2].m_y = maxy;
vertex[2].m_z = zz;
vertex[2].m_abgr = 0xffff0000;
vertex[2].m_u = maxu;
vertex[2].m_v = maxv;
vertex[3].m_x = minx;
vertex[3].m_y = maxy;
vertex[3].m_z = zz;
vertex[3].m_abgr = 0xffffffff;
vertex[3].m_u = minu;
vertex[3].m_v = maxv;
uint16_t* indices = (uint16_t*)tib.data;
indices[0] = 0;
indices[1] = 2;
indices[2] = 1;
indices[3] = 0;
indices[4] = 3;
indices[5] = 2;
bgfx::setState(BGFX_STATE_DEFAULT);
bgfx::setIndexBuffer(&tib);
bgfx::setVertexBuffer(0, &tvb);
bgfx::submit(_view, _program);
}
}
class ExampleRaymarch : public entry::AppI
{
public:
ExampleRaymarch(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_NONE;
m_reset = BGFX_RESET_VSYNC;
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.
PosColorTexCoord0Vertex::init();
u_mtx = bgfx::createUniform("u_mtx", bgfx::UniformType::Mat4);
u_lightDirTime = bgfx::createUniform("u_lightDirTime", bgfx::UniformType::Vec4);
// Create program from shaders.
m_program = loadProgram("vs_raymarching", "fs_raymarching");
m_timeOffset = bx::getHPCounter();
imguiCreate();
}
int shutdown() override
{
imguiDestroy();
// Cleanup.
bgfx::destroy(m_program);
bgfx::destroy(u_mtx);
bgfx::destroy(u_lightDirTime);
// 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);
imguiEndFrame();
// Set view 0 default viewport.
bgfx::setViewRect(0, 0, 0, uint16_t(m_width), uint16_t(m_height) );
// Set view 1 default viewport.
bgfx::setViewRect(1, 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 viewZ 0.
bgfx::touch(0);
const bx::Vec3 at = { 0.0f, 0.0f, 0.0f };
const bx::Vec3 eye = { 0.0f, 0.0f, -15.0f };
float view[16];
float proj[16];
bx::mtxLookAt(view, eye, at);
const bgfx::Caps* caps = bgfx::getCaps();
bx::mtxProj(proj, 60.0f, float(m_width)/float(m_height), 0.1f, 100.0f, caps->homogeneousDepth);
// Set view and projection matrix for view 1.
bgfx::setViewTransform(0, view, proj);
float ortho[16];
bx::mtxOrtho(ortho, 0.0f, 1280.0f, 720.0f, 0.0f, 0.0f, 100.0f, 0.0, caps->homogeneousDepth);
// Set view and projection matrix for view 0.
bgfx::setViewTransform(1, NULL, ortho);
float time = (float)( (bx::getHPCounter()-m_timeOffset)/double(bx::getHPFrequency() ) );
float vp[16];
bx::mtxMul(vp, view, proj);
float mtx[16];
bx::mtxRotateXY(mtx
, time
, time*0.37f
);
float mtxInv[16];
bx::mtxInverse(mtxInv, mtx);
float lightDirTime[4];
const bx::Vec3 lightDirModelN = bx::normalize(bx::Vec3{-0.4f, -0.5f, -1.0f});
bx::store(lightDirTime, bx::mul(lightDirModelN, mtxInv) );
lightDirTime[3] = time;
bgfx::setUniform(u_lightDirTime, lightDirTime);
float mvp[16];
bx::mtxMul(mvp, mtx, vp);
float invMvp[16];
bx::mtxInverse(invMvp, mvp);
bgfx::setUniform(u_mtx, invMvp);
renderScreenSpaceQuad(1, m_program, 0.0f, 0.0f, 1280.0f, 720.0f);
// 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;
int64_t m_timeOffset;
bgfx::UniformHandle u_mtx;
bgfx::UniformHandle u_lightDirTime;
bgfx::ProgramHandle m_program;
};
} // namespace
ENTRY_IMPLEMENT_MAIN(
ExampleRaymarch
, "03-raymarch"
, "Updating shader uniforms."
, "https://bkaradzic.github.io/bgfx/examples.html#raymarch"
);