browser/external/raylib-4.5.0/examples/others/rlgl_compute_shader.c
2023-09-27 15:02:24 -04:00

175 lines
7.2 KiB
C

/*******************************************************************************************
*
* raylib [rlgl] example - compute shader - Conway's Game of Life
*
* NOTE: This example requires raylib OpenGL 4.3 versions for compute shaders support,
* shaders used in this example are #version 430 (OpenGL 4.3)
*
* Example originally created with raylib 4.0, last time updated with raylib 2.5
*
* Example contributed by Teddy Astie (@tsnake41) and reviewed by Ramon Santamaria (@raysan5)
*
* Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
* BSD-like license that allows static linking with closed source software
*
* Copyright (c) 2021-2023 Teddy Astie (@tsnake41)
*
********************************************************************************************/
#include "raylib.h"
#include "rlgl.h"
#include <stdlib.h>
// IMPORTANT: This must match gol*.glsl GOL_WIDTH constant.
// This must be a multiple of 16 (check golLogic compute dispatch).
#define GOL_WIDTH 768
// Maximum amount of queued draw commands (squares draw from mouse down events).
#define MAX_BUFFERED_TRANSFERTS 48
// Game Of Life Update Command
typedef struct GolUpdateCmd {
unsigned int x; // x coordinate of the gol command
unsigned int y; // y coordinate of the gol command
unsigned int w; // width of the filled zone
unsigned int enabled; // whether to enable or disable zone
} GolUpdateCmd;
// Game Of Life Update Commands SSBO
typedef struct GolUpdateSSBO {
unsigned int count;
GolUpdateCmd commands[MAX_BUFFERED_TRANSFERTS];
} GolUpdateSSBO;
//------------------------------------------------------------------------------------
// Program main entry point
//------------------------------------------------------------------------------------
int main(void)
{
// Initialization
//--------------------------------------------------------------------------------------
InitWindow(GOL_WIDTH, GOL_WIDTH, "raylib [rlgl] example - compute shader - game of life");
const Vector2 resolution = { GOL_WIDTH, GOL_WIDTH };
unsigned int brushSize = 8;
// Game of Life logic compute shader
char *golLogicCode = LoadFileText("resources/shaders/glsl430/gol.glsl");
unsigned int golLogicShader = rlCompileShader(golLogicCode, RL_COMPUTE_SHADER);
unsigned int golLogicProgram = rlLoadComputeShaderProgram(golLogicShader);
UnloadFileText(golLogicCode);
// Game of Life logic render shader
Shader golRenderShader = LoadShader(NULL, "resources/shaders/glsl430/gol_render.glsl");
int resUniformLoc = GetShaderLocation(golRenderShader, "resolution");
// Game of Life transfert shader (CPU<->GPU download and upload)
char *golTransfertCode = LoadFileText("resources/shaders/glsl430/gol_transfert.glsl");
unsigned int golTransfertShader = rlCompileShader(golTransfertCode, RL_COMPUTE_SHADER);
unsigned int golTransfertProgram = rlLoadComputeShaderProgram(golTransfertShader);
UnloadFileText(golTransfertCode);
// Load shader storage buffer object (SSBO), id returned
unsigned int ssboA = rlLoadShaderBuffer(GOL_WIDTH*GOL_WIDTH*sizeof(unsigned int), NULL, RL_DYNAMIC_COPY);
unsigned int ssboB = rlLoadShaderBuffer(GOL_WIDTH*GOL_WIDTH*sizeof(unsigned int), NULL, RL_DYNAMIC_COPY);
unsigned int ssboTransfert = rlLoadShaderBuffer(sizeof(GolUpdateSSBO), NULL, RL_DYNAMIC_COPY);
GolUpdateSSBO transfertBuffer = { 0 };
// Create a white texture of the size of the window to update
// each pixel of the window using the fragment shader: golRenderShader
Image whiteImage = GenImageColor(GOL_WIDTH, GOL_WIDTH, WHITE);
Texture whiteTex = LoadTextureFromImage(whiteImage);
UnloadImage(whiteImage);
//--------------------------------------------------------------------------------------
// Main game loop
while (!WindowShouldClose())
{
// Update
//----------------------------------------------------------------------------------
brushSize += (int)GetMouseWheelMove();
if ((IsMouseButtonDown(MOUSE_BUTTON_LEFT) || IsMouseButtonDown(MOUSE_BUTTON_RIGHT))
&& (transfertBuffer.count < MAX_BUFFERED_TRANSFERTS))
{
// Buffer a new command
transfertBuffer.commands[transfertBuffer.count].x = GetMouseX() - brushSize/2;
transfertBuffer.commands[transfertBuffer.count].y = GetMouseY() - brushSize/2;
transfertBuffer.commands[transfertBuffer.count].w = brushSize;
transfertBuffer.commands[transfertBuffer.count].enabled = IsMouseButtonDown(MOUSE_BUTTON_LEFT);
transfertBuffer.count++;
}
else if (transfertBuffer.count > 0) // Process transfert buffer
{
// Send SSBO buffer to GPU
rlUpdateShaderBuffer(ssboTransfert, &transfertBuffer, sizeof(GolUpdateSSBO), 0);
// Process SSBO commands on GPU
rlEnableShader(golTransfertProgram);
rlBindShaderBuffer(ssboA, 1);
rlBindShaderBuffer(ssboTransfert, 3);
rlComputeShaderDispatch(transfertBuffer.count, 1, 1); // Each GPU unit will process a command!
rlDisableShader();
transfertBuffer.count = 0;
}
else
{
// Process game of life logic
rlEnableShader(golLogicProgram);
rlBindShaderBuffer(ssboA, 1);
rlBindShaderBuffer(ssboB, 2);
rlComputeShaderDispatch(GOL_WIDTH/16, GOL_WIDTH/16, 1);
rlDisableShader();
// ssboA <-> ssboB
int temp = ssboA;
ssboA = ssboB;
ssboB = temp;
}
rlBindShaderBuffer(ssboA, 1);
SetShaderValue(golRenderShader, resUniformLoc, &resolution, SHADER_UNIFORM_VEC2);
//----------------------------------------------------------------------------------
// Draw
//----------------------------------------------------------------------------------
BeginDrawing();
ClearBackground(BLANK);
BeginShaderMode(golRenderShader);
DrawTexture(whiteTex, 0, 0, WHITE);
EndShaderMode();
DrawRectangleLines(GetMouseX() - brushSize/2, GetMouseY() - brushSize/2, brushSize, brushSize, RED);
DrawText("Use Mouse wheel to increase/decrease brush size", 10, 10, 20, WHITE);
DrawFPS(GetScreenWidth() - 100, 10);
EndDrawing();
//----------------------------------------------------------------------------------
}
// De-Initialization
//--------------------------------------------------------------------------------------
// Unload shader buffers objects.
rlUnloadShaderBuffer(ssboA);
rlUnloadShaderBuffer(ssboB);
rlUnloadShaderBuffer(ssboTransfert);
// Unload compute shader programs
rlUnloadShaderProgram(golTransfertProgram);
rlUnloadShaderProgram(golLogicProgram);
UnloadTexture(whiteTex); // Unload white texture
UnloadShader(golRenderShader); // Unload rendering fragment shader
CloseWindow(); // Close window and OpenGL context
//--------------------------------------------------------------------------------------
return 0;
}