raylib/examples/shaders/shaders_julia_set.c
2021-04-07 12:25:04 +02:00

194 lines
8.6 KiB
C

/*******************************************************************************************
*
* raylib [shaders] example - julia sets
*
* NOTE: This example requires raylib OpenGL 3.3 or ES2 versions for shaders support,
* OpenGL 1.1 does not support shaders, recompile raylib to OpenGL 3.3 version.
*
* NOTE: Shaders used in this example are #version 330 (OpenGL 3.3).
*
* This example has been created using raylib 2.5 (www.raylib.com)
* raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
*
* Example contributed by eggmund (@eggmund) and reviewed by Ramon Santamaria (@raysan5)
*
* Copyright (c) 2019 eggmund (@eggmund) and Ramon Santamaria (@raysan5)
*
********************************************************************************************/
#include "raylib.h"
#if defined(PLATFORM_DESKTOP)
#define GLSL_VERSION 330
#else // PLATFORM_RPI, PLATFORM_ANDROID, PLATFORM_WEB
#define GLSL_VERSION 100
#endif
// A few good julia sets
const float pointsOfInterest[6][2] =
{
{ -0.348827, 0.607167 },
{ -0.786268, 0.169728 },
{ -0.8, 0.156 },
{ 0.285, 0.0 },
{ -0.835, -0.2321 },
{ -0.70176, -0.3842 },
};
int main(void)
{
// Initialization
//--------------------------------------------------------------------------------------
const int screenWidth = 800;
const int screenHeight = 450;
//SetConfigFlags(FLAG_WINDOW_HIGHDPI);
InitWindow(screenWidth, screenHeight, "raylib [shaders] example - julia sets");
// Load julia set shader
// NOTE: Defining 0 (NULL) for vertex shader forces usage of internal default vertex shader
Shader shader = LoadShader(0, TextFormat("resources/shaders/glsl%i/julia_set.fs", GLSL_VERSION));
// Create a RenderTexture2D to be used for render to texture
RenderTexture2D target = LoadRenderTexture(GetScreenWidth(), GetScreenHeight());
// c constant to use in z^2 + c
float c[2] = { pointsOfInterest[0][0], pointsOfInterest[0][1] };
// Offset and zoom to draw the julia set at. (centered on screen and default size)
float offset[2] = { -(float)GetScreenWidth()/2, -(float)GetScreenHeight()/2 };
float zoom = 1.0f;
Vector2 offsetSpeed = { 0.0f, 0.0f };
// Get variable (uniform) locations on the shader to connect with the program
// NOTE: If uniform variable could not be found in the shader, function returns -1
int cLoc = GetShaderLocation(shader, "c");
int zoomLoc = GetShaderLocation(shader, "zoom");
int offsetLoc = GetShaderLocation(shader, "offset");
// Tell the shader what the screen dimensions, zoom, offset and c are
float screenDims[2] = { (float)GetScreenWidth(), (float)GetScreenHeight() };
SetShaderValue(shader, GetShaderLocation(shader, "screenDims"), screenDims, SHADER_UNIFORM_VEC2);
SetShaderValue(shader, cLoc, c, SHADER_UNIFORM_VEC2);
SetShaderValue(shader, zoomLoc, &zoom, SHADER_UNIFORM_FLOAT);
SetShaderValue(shader, offsetLoc, offset, SHADER_UNIFORM_VEC2);
int incrementSpeed = 0; // Multiplier of speed to change c value
bool showControls = true; // Show controls
bool pause = false; // Pause animation
SetTargetFPS(60); // Set our game to run at 60 frames-per-second
//--------------------------------------------------------------------------------------
// Main game loop
while (!WindowShouldClose()) // Detect window close button or ESC key
{
// Update
//----------------------------------------------------------------------------------
// Press [1 - 6] to reset c to a point of interest
if (IsKeyPressed(KEY_ONE) ||
IsKeyPressed(KEY_TWO) ||
IsKeyPressed(KEY_THREE) ||
IsKeyPressed(KEY_FOUR) ||
IsKeyPressed(KEY_FIVE) ||
IsKeyPressed(KEY_SIX))
{
if (IsKeyPressed(KEY_ONE)) c[0] = pointsOfInterest[0][0], c[1] = pointsOfInterest[0][1];
else if (IsKeyPressed(KEY_TWO)) c[0] = pointsOfInterest[1][0], c[1] = pointsOfInterest[1][1];
else if (IsKeyPressed(KEY_THREE)) c[0] = pointsOfInterest[2][0], c[1] = pointsOfInterest[2][1];
else if (IsKeyPressed(KEY_FOUR)) c[0] = pointsOfInterest[3][0], c[1] = pointsOfInterest[3][1];
else if (IsKeyPressed(KEY_FIVE)) c[0] = pointsOfInterest[4][0], c[1] = pointsOfInterest[4][1];
else if (IsKeyPressed(KEY_SIX)) c[0] = pointsOfInterest[5][0], c[1] = pointsOfInterest[5][1];
SetShaderValue(shader, cLoc, c, SHADER_UNIFORM_VEC2);
}
if (IsKeyPressed(KEY_SPACE)) pause = !pause; // Pause animation (c change)
if (IsKeyPressed(KEY_F1)) showControls = !showControls; // Toggle whether or not to show controls
if (!pause)
{
if (IsKeyPressed(KEY_RIGHT)) incrementSpeed++;
else if (IsKeyPressed(KEY_LEFT)) incrementSpeed--;
// TODO: The idea is to zoom and move around with mouse
// Probably offset movement should be proportional to zoom level
if (IsMouseButtonDown(MOUSE_LEFT_BUTTON) || IsMouseButtonDown(MOUSE_RIGHT_BUTTON))
{
if (IsMouseButtonDown(MOUSE_LEFT_BUTTON)) zoom += zoom*0.003f;
if (IsMouseButtonDown(MOUSE_RIGHT_BUTTON)) zoom -= zoom*0.003f;
Vector2 mousePos = GetMousePosition();
offsetSpeed.x = mousePos.x -(float)screenWidth/2;
offsetSpeed.y = mousePos.y -(float)screenHeight/2;
// Slowly move camera to targetOffset
offset[0] += GetFrameTime()*offsetSpeed.x*0.8f;
offset[1] += GetFrameTime()*offsetSpeed.y*0.8f;
}
else offsetSpeed = (Vector2){ 0.0f, 0.0f };
SetShaderValue(shader, zoomLoc, &zoom, SHADER_UNIFORM_FLOAT);
SetShaderValue(shader, offsetLoc, offset, SHADER_UNIFORM_VEC2);
// Increment c value with time
float amount = GetFrameTime()*incrementSpeed*0.0005f;
c[0] += amount;
c[1] += amount;
SetShaderValue(shader, cLoc, c, SHADER_UNIFORM_VEC2);
}
//----------------------------------------------------------------------------------
// Draw
//----------------------------------------------------------------------------------
BeginDrawing();
ClearBackground(BLACK); // Clear the screen of the previous frame.
// Using a render texture to draw Julia set
BeginTextureMode(target); // Enable drawing to texture
ClearBackground(BLACK); // Clear the render texture
// Draw a rectangle in shader mode to be used as shader canvas
// NOTE: Rectangle uses font white character texture coordinates,
// so shader can not be applied here directly because input vertexTexCoord
// do not represent full screen coordinates (space where want to apply shader)
DrawRectangle(0, 0, GetScreenWidth(), GetScreenHeight(), BLACK);
EndTextureMode();
// Draw the saved texture and rendered julia set with shader
// NOTE: We do not invert texture on Y, already considered inside shader
BeginShaderMode(shader);
// WARNING: If FLAG_WINDOW_HIGHDPI is enabled, HighDPI monitor scaling should be considered
// when rendering the RenderTexture2D to fit in the HighDPI scaled Window
DrawTextureEx(target.texture, (Vector2){ 0.0f, 0.0f }, 0.0f, 1.0f, WHITE);
EndShaderMode();
if (showControls)
{
DrawText("Press Mouse buttons right/left to zoom in/out and move", 10, 15, 10, RAYWHITE);
DrawText("Press KEY_F1 to toggle these controls", 10, 30, 10, RAYWHITE);
DrawText("Press KEYS [1 - 6] to change point of interest", 10, 45, 10, RAYWHITE);
DrawText("Press KEY_LEFT | KEY_RIGHT to change speed", 10, 60, 10, RAYWHITE);
DrawText("Press KEY_SPACE to pause movement animation", 10, 75, 10, RAYWHITE);
}
EndDrawing();
//----------------------------------------------------------------------------------
}
// De-Initialization
//--------------------------------------------------------------------------------------
UnloadShader(shader); // Unload shader
UnloadRenderTexture(target); // Unload render texture
CloseWindow(); // Close window and OpenGL context
//--------------------------------------------------------------------------------------
return 0;
}