1/*******************************************************************************************
2*
3* raylib [shaders] example - julia sets
4*
5* NOTE: This example requires raylib OpenGL 3.3 or ES2 versions for shaders support,
6* OpenGL 1.1 does not support shaders, recompile raylib to OpenGL 3.3 version.
7*
8* NOTE: Shaders used in this example are #version 330 (OpenGL 3.3).
9*
10* This example has been created using raylib 2.5 (www.raylib.com)
11* raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
12*
13* Example contributed by eggmund (@eggmund) and reviewed by Ramon Santamaria (@raysan5)
14*
15* Copyright (c) 2019 eggmund (@eggmund) and Ramon Santamaria (@raysan5)
16*
17********************************************************************************************/
18
19#include "raylib.h"
20
21#if defined(PLATFORM_DESKTOP)
22 #define GLSL_VERSION 330
23#else // PLATFORM_RPI, PLATFORM_ANDROID, PLATFORM_WEB
24 #define GLSL_VERSION 100
25#endif
26
27// A few good julia sets
28const float POINTS_OF_INTEREST[6][2] =
29{
30 { -0.348827, 0.607167 },
31 { -0.786268, 0.169728 },
32 { -0.8, 0.156 },
33 { 0.285, 0.0 },
34 { -0.835, -0.2321 },
35 { -0.70176, -0.3842 },
36};
37
38int main(void)
39{
40 // Initialization
41 //--------------------------------------------------------------------------------------
42 const int screenWidth = 800;
43 const int screenHeight = 450;
44
45 InitWindow(screenWidth, screenHeight, "raylib [shaders] example - julia sets");
46
47 // Load julia set shader
48 // NOTE: Defining 0 (NULL) for vertex shader forces usage of internal default vertex shader
49 Shader shader = LoadShader(0, FormatText("resources/shaders/glsl%i/julia_set.fs", GLSL_VERSION));
50
51 // c constant to use in z^2 + c
52 float c[2] = { POINTS_OF_INTEREST[0][0], POINTS_OF_INTEREST[0][1] };
53
54 // Offset and zoom to draw the julia set at. (centered on screen and default size)
55 float offset[2] = { -(float)screenWidth/2, -(float)screenHeight/2 };
56 float zoom = 1.0f;
57
58 Vector2 offsetSpeed = { 0.0f, 0.0f };
59
60 // Get variable (uniform) locations on the shader to connect with the program
61 // NOTE: If uniform variable could not be found in the shader, function returns -1
62 int cLoc = GetShaderLocation(shader, "c");
63 int zoomLoc = GetShaderLocation(shader, "zoom");
64 int offsetLoc = GetShaderLocation(shader, "offset");
65
66 // Tell the shader what the screen dimensions, zoom, offset and c are
67 float screenDims[2] = { (float)screenWidth, (float)screenHeight };
68 SetShaderValue(shader, GetShaderLocation(shader, "screenDims"), screenDims, UNIFORM_VEC2);
69
70 SetShaderValue(shader, cLoc, c, UNIFORM_VEC2);
71 SetShaderValue(shader, zoomLoc, &zoom, UNIFORM_FLOAT);
72 SetShaderValue(shader, offsetLoc, offset, UNIFORM_VEC2);
73
74 // Create a RenderTexture2D to be used for render to texture
75 RenderTexture2D target = LoadRenderTexture(screenWidth, screenHeight);
76
77 int incrementSpeed = 0; // Multiplier of speed to change c value
78 bool showControls = true; // Show controls
79 bool pause = false; // Pause animation
80
81 SetTargetFPS(60); // Set our game to run at 60 frames-per-second
82 //--------------------------------------------------------------------------------------
83
84 // Main game loop
85 while (!WindowShouldClose()) // Detect window close button or ESC key
86 {
87 // Update
88 //----------------------------------------------------------------------------------
89 // Press [1 - 6] to reset c to a point of interest
90 if (IsKeyPressed(KEY_ONE) ||
91 IsKeyPressed(KEY_TWO) ||
92 IsKeyPressed(KEY_THREE) ||
93 IsKeyPressed(KEY_FOUR) ||
94 IsKeyPressed(KEY_FIVE) ||
95 IsKeyPressed(KEY_SIX))
96 {
97 if (IsKeyPressed(KEY_ONE)) c[0] = POINTS_OF_INTEREST[0][0], c[1] = POINTS_OF_INTEREST[0][1];
98 else if (IsKeyPressed(KEY_TWO)) c[0] = POINTS_OF_INTEREST[1][0], c[1] = POINTS_OF_INTEREST[1][1];
99 else if (IsKeyPressed(KEY_THREE)) c[0] = POINTS_OF_INTEREST[2][0], c[1] = POINTS_OF_INTEREST[2][1];
100 else if (IsKeyPressed(KEY_FOUR)) c[0] = POINTS_OF_INTEREST[3][0], c[1] = POINTS_OF_INTEREST[3][1];
101 else if (IsKeyPressed(KEY_FIVE)) c[0] = POINTS_OF_INTEREST[4][0], c[1] = POINTS_OF_INTEREST[4][1];
102 else if (IsKeyPressed(KEY_SIX)) c[0] = POINTS_OF_INTEREST[5][0], c[1] = POINTS_OF_INTEREST[5][1];
103
104 SetShaderValue(shader, cLoc, c, UNIFORM_VEC2);
105 }
106
107 if (IsKeyPressed(KEY_SPACE)) pause = !pause; // Pause animation (c change)
108 if (IsKeyPressed(KEY_F1)) showControls = !showControls; // Toggle whether or not to show controls
109
110 if (!pause)
111 {
112 if (IsKeyPressed(KEY_RIGHT)) incrementSpeed++;
113 else if (IsKeyPressed(KEY_LEFT)) incrementSpeed--;
114
115 // TODO: The idea is to zoom and move around with mouse
116 // Probably offset movement should be proportional to zoom level
117 if (IsMouseButtonDown(MOUSE_LEFT_BUTTON) || IsMouseButtonDown(MOUSE_RIGHT_BUTTON))
118 {
119 if (IsMouseButtonDown(MOUSE_LEFT_BUTTON)) zoom += zoom*0.003f;
120 if (IsMouseButtonDown(MOUSE_RIGHT_BUTTON)) zoom -= zoom*0.003f;
121
122 Vector2 mousePos = GetMousePosition();
123
124 offsetSpeed.x = mousePos.x -(float)screenWidth/2;
125 offsetSpeed.y = mousePos.y -(float)screenHeight/2;
126
127 // Slowly move camera to targetOffset
128 offset[0] += GetFrameTime()*offsetSpeed.x*0.8f;
129 offset[1] += GetFrameTime()*offsetSpeed.y*0.8f;
130 }
131 else offsetSpeed = (Vector2){ 0.0f, 0.0f };
132
133 SetShaderValue(shader, zoomLoc, &zoom, UNIFORM_FLOAT);
134 SetShaderValue(shader, offsetLoc, offset, UNIFORM_VEC2);
135
136 // Increment c value with time
137 float amount = GetFrameTime()*incrementSpeed*0.0005f;
138 c[0] += amount;
139 c[1] += amount;
140
141 SetShaderValue(shader, cLoc, c, UNIFORM_VEC2);
142 }
143 //----------------------------------------------------------------------------------
144
145 // Draw
146 //----------------------------------------------------------------------------------
147 BeginDrawing();
148
149 ClearBackground(BLACK); // Clear the screen of the previous frame.
150
151 // Using a render texture to draw Julia set
152 BeginTextureMode(target); // Enable drawing to texture
153 ClearBackground(BLACK); // Clear the render texture
154
155 // Draw a rectangle in shader mode to be used as shader canvas
156 // NOTE: Rectangle uses font white character texture coordinates,
157 // so shader can not be applied here directly because input vertexTexCoord
158 // do not represent full screen coordinates (space where want to apply shader)
159 DrawRectangle(0, 0, GetScreenWidth(), GetScreenHeight(), BLACK);
160 EndTextureMode();
161
162 // Draw the saved texture and rendered julia set with shader
163 // NOTE: We do not invert texture on Y, already considered inside shader
164 BeginShaderMode(shader);
165 DrawTexture(target.texture, 0, 0, WHITE);
166 EndShaderMode();
167
168 if (showControls)
169 {
170 DrawText("Press Mouse buttons right/left to zoom in/out and move", 10, 15, 10, RAYWHITE);
171 DrawText("Press KEY_F1 to toggle these controls", 10, 30, 10, RAYWHITE);
172 DrawText("Press KEYS [1 - 6] to change point of interest", 10, 45, 10, RAYWHITE);
173 DrawText("Press KEY_LEFT | KEY_RIGHT to change speed", 10, 60, 10, RAYWHITE);
174 DrawText("Press KEY_SPACE to pause movement animation", 10, 75, 10, RAYWHITE);
175 }
176
177 EndDrawing();
178 //----------------------------------------------------------------------------------
179 }
180
181 // De-Initialization
182 //--------------------------------------------------------------------------------------
183 UnloadShader(shader); // Unload shader
184 UnloadRenderTexture(target); // Unload render texture
185
186 CloseWindow(); // Close window and OpenGL context
187 //--------------------------------------------------------------------------------------
188
189 return 0;
190}
191