Add an example that generates a random sequence. (#3846)

5 files changed, 182 insertions, 0 deletions

diff --git a/examples/Makefile b/examples/Makefile
index 8362b8c8..9ce05da5 100644
--- a/examples/Makefile
+++ b/examples/Makefile
@@ -453,6 +453,7 @@ CORE = \
     core/core_input_mouse_wheel \
     core/core_input_multitouch \
     core/core_loading_thread \
+    core/core_random_sequence \
     core/core_random_values \
     core/core_scissor_test \
     core/core_smooth_pixelperfect \
diff --git a/examples/Makefile.Web b/examples/Makefile.Web
index 204db50c..af3325aa 100644
--- a/examples/Makefile.Web
+++ b/examples/Makefile.Web
@@ -359,6 +359,7 @@ CORE = \
     core/core_input_mouse_wheel \
     core/core_input_multitouch \
     core/core_loading_thread \
+    core/core_random_sequence \
     core/core_random_values \
     core/core_scissor_test \
     core/core_smooth_pixelperfect \
@@ -588,6 +589,9 @@ core/core_input_multitouch: core/core_input_multitouch.c
 core/core_loading_thread: core/core_loading_thread.c
 	$(CC) -o $@$(EXT) $< $(CFLAGS) $(INCLUDE_PATHS) $(LDFLAGS) $(LDLIBS) -D$(PLATFORM) -sUSE_PTHREADS=1
 
+core/core_random_sequence: core/core_random_sequence.c
+	$(CC) -o $@$(EXT) $< $(CFLAGS) $(INCLUDE_PATHS) $(LDFLAGS) $(LDLIBS) -D$(PLATFORM)
+
 core/core_random_values: core/core_random_values.c
 	$(CC) -o $@$(EXT) $< $(CFLAGS) $(INCLUDE_PATHS) $(LDFLAGS) $(LDLIBS) -D$(PLATFORM)
 
diff --git a/examples/README.md b/examples/README.md
index 0fed8acd..94f5369d 100644
--- a/examples/README.md
+++ b/examples/README.md
@@ -55,6 +55,7 @@ Examples using raylib core platform functionality like window creation, inputs,
 | 29 | [core_custom_frame_control](core/core_custom_frame_control.c) | <img src="core/core_custom_frame_control.png" alt="core_custom_frame_control" width="80"> | ⭐️⭐️⭐️⭐️ | **4.0** | **4.0** | [Ray](https://github.com/raysan5) |
 | 30 | [core_smooth_pixelperfect](core/core_smooth_pixelperfect.c) | <img src="core/core_smooth_pixelperfect.png" alt="core_smooth_pixelperfect" width="80"> | ⭐️⭐️⭐️☆ | 3.7 | **4.0** | [Giancamillo Alessandroni](https://github.com/NotManyIdeasDev) |
 | 31 | [core_window_should_close](core/core_window_should_close.c) | <img src="core/core_window_should_close.png" alt="core_window_should_close" width="80"> | ⭐️⭐️☆☆ | **4.2** | **4.2** | [Ray](https://github.com/raysan5) |
+| 32 | [core_random_sequence](core/core_random_sequence.c) | <img src="core/core_random_sequence.png" alt="core_random_sequence" width="80"> | ⭐️☆☆☆ | **5.0** | **5.0** | [REDl3east](https://github.com/REDl3east) |
 
 ### category: shapes
 
diff --git a/examples/core/core_random_sequence.c b/examples/core/core_random_sequence.c
new file mode 100644
index 00000000..c946b64d
--- /dev/null
+++ b/examples/core/core_random_sequence.c
@@ -0,0 +1,176 @@
+/*******************************************************************************************
+*
+*   raylib [core] example - Generates a random sequence
+*
+*   Example originally created with raylib 5.0, last time updated with raylib 5.0
+*
+*   Example contributed by Dalton Overmyer (@REDl3east) 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) 2023 Dalton Overmyer (@REDl3east)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+#include "raymath.h"
+
+#include <stdlib.h> // Required for: malloc() and free()
+
+typedef struct ColorRect{
+  Color c;
+  Rectangle r;
+} ColorRect;
+
+static Color GenerateRandomColor();
+static ColorRect* GenerateRandomColorRectSequence(float rectCount, float rectWidth, float screenWidth, float screenHeight);
+static void ShuffleColorRectSequence(ColorRect* rectangles, int rectCount);
+static void DrawTextCenterKeyHelp(const char* key, const char* text, int posX, int posY, int fontSize, Color color);
+
+//------------------------------------------------------------------------------------
+// Program main entry point
+//------------------------------------------------------------------------------------
+int main(void) {
+  // Initialization
+  //--------------------------------------------------------------------------------------
+  const int screenWidth = 800;
+  const int screenHeight = 450;
+
+  InitWindow(screenWidth, screenHeight, "raylib [core] example - Generates a random sequence");
+
+  int rectCount = 20;
+  float rectSize = (float)screenWidth/rectCount;
+  ColorRect* rectangles = GenerateRandomColorRectSequence(rectCount, rectSize, screenWidth, 0.75f * screenHeight);
+
+  SetTargetFPS(60);
+  //--------------------------------------------------------------------------------------
+
+  // Main game loop
+  while (!WindowShouldClose()) // Detect window close button or ESC key
+  {
+    // Update
+    //----------------------------------------------------------------------------------
+
+    if(IsKeyPressed(KEY_SPACE))
+    {
+      ShuffleColorRectSequence(rectangles, rectCount);
+    }
+
+    if(IsKeyPressed(KEY_UP))
+    {
+      rectCount++;
+      rectSize = (float)screenWidth/rectCount;
+      free(rectangles);
+      rectangles = GenerateRandomColorRectSequence(rectCount, rectSize, screenWidth, 0.75f * screenHeight);
+    }
+
+    if(IsKeyPressed(KEY_DOWN))
+    {
+      if(rectCount >= 4){
+        rectCount--;
+        rectSize = (float)screenWidth/rectCount;
+        free(rectangles);
+        rectangles = GenerateRandomColorRectSequence(rectCount, rectSize, screenWidth, 0.75f * screenHeight);
+      }
+    }
+
+    // Draw
+    //----------------------------------------------------------------------------------
+    BeginDrawing();
+
+    ClearBackground(RAYWHITE);
+    
+    int fontSize = 20;
+    for(int x=0;x<rectCount;x++)
+    {
+      DrawRectangleRec(rectangles[x].r, rectangles[x].c);
+      DrawTextCenterKeyHelp("SPACE", "to shuffle the sequence.", 10, screenHeight - 96, fontSize, BLACK);
+      DrawTextCenterKeyHelp("UP", "to add a rectangle and generate a new sequence.", 10, screenHeight - 64, fontSize, BLACK);
+      DrawTextCenterKeyHelp("DOWN", "to remove a rectangle and generate a new sequence.", 10, screenHeight - 32, fontSize, BLACK);
+    }
+
+    const char* rectCountText = TextFormat("%d rectangles", rectCount);
+    int rectCountTextSize = MeasureText(rectCountText, fontSize);
+    DrawText(rectCountText, screenWidth - rectCountTextSize - 10, 10, fontSize, BLACK);
+
+    DrawFPS(10, 10);
+
+    EndDrawing();
+    //----------------------------------------------------------------------------------
+  }
+
+  // De-Initialization
+  //--------------------------------------------------------------------------------------
+
+  free(rectangles);
+  CloseWindow(); // Close window and OpenGL context
+  //--------------------------------------------------------------------------------------
+
+  return 0;
+}
+
+static Color GenerateRandomColor()
+{
+  return CLITERAL(Color){
+    GetRandomValue(0, 255),
+    GetRandomValue(0, 255),
+    GetRandomValue(0, 255),
+    255,
+  };
+}
+
+static ColorRect* GenerateRandomColorRectSequence(float rectCount, float rectWidth, float screenWidth, float screenHeight){
+  int *seq = LoadRandomSequence(rectCount, 0, rectCount-1);
+  ColorRect* rectangles = (ColorRect *)malloc(rectCount*sizeof(ColorRect));
+
+  float rectSeqWidth = rectCount * rectWidth;
+  int startX = (screenWidth - rectSeqWidth) * 0.5f;
+
+  for(int x=0;x<rectCount;x++){
+    int rectHeight = Remap(seq[x], 0, rectCount-1, 0, screenHeight);
+    rectangles[x].c = GenerateRandomColor();
+    rectangles[x].r = CLITERAL(Rectangle){
+      startX + x * rectWidth, screenHeight - rectHeight, rectWidth, rectHeight
+    };
+  }
+  UnloadRandomSequence(seq);
+  return rectangles;
+}
+
+static void ShuffleColorRectSequence(ColorRect* rectangles, int rectCount)
+{
+  int *seq = LoadRandomSequence(rectCount, 0, rectCount-1);
+  for(int i1=0;i1<rectCount;i1++){
+    ColorRect* r1 = &rectangles[i1];
+    ColorRect* r2 = &rectangles[seq[i1]];
+
+    // swap only the color and height
+    ColorRect tmp = *r1;
+    r1->c = r2->c;
+    r1->r.height = r2->r.height;
+    r1->r.y = r2->r.y;
+    r2->c = tmp.c;
+    r2->r.height = tmp.r.height;
+    r2->r.y = tmp.r.y;
+
+  }
+  UnloadRandomSequence(seq);
+}
+
+static void DrawTextCenterKeyHelp(const char* key, const char* text, int posX, int posY, int fontSize, Color color)
+{
+  int spaceSize = MeasureText(" ", fontSize); 
+  int pressSize = MeasureText("Press", fontSize); 
+  int keySize = MeasureText(key, fontSize); 
+  int textSize = MeasureText(text, fontSize); 
+  int totalSize = pressSize + 2 * spaceSize + keySize + 2 * spaceSize + textSize;
+  int textSizeCurrent = 0;
+
+  DrawText("Press", posX, posY, fontSize, color);
+  textSizeCurrent += pressSize + 2 * spaceSize;
+  DrawText(key, posX + textSizeCurrent, posY, fontSize, RED);
+  DrawRectangle(posX + textSizeCurrent, posY + fontSize, keySize, 3, RED);
+  textSizeCurrent += keySize + 2 * spaceSize;
+  DrawText(text, posX + textSizeCurrent, posY, fontSize, color);
+}
\ No newline at end of file
diff --git a/examples/core/core_random_sequence.png b/examples/core/core_random_sequence.png
new file mode 100644
index 00000000..206aa8b4
--- /dev/null
+++ b/examples/core/core_random_sequence.png