git subrepo clone (merge) https://github.com/HarbourMasters/otrgui.git OTRGui

subrepo:
  subdir:   "OTRGui"
  merged:   "a6066a251"
upstream:
  origin:   "https://github.com/HarbourMasters/otrgui.git"
  branch:   "master"
  commit:   "a6066a251"
git-subrepo:
  version:  "0.4.1"
  origin:   "???"
  commit:   "???"

OTRGui/libs/raylib/examples/textures/textures_image_processing.c

@@ -0,0 +1,169 @@
+/*******************************************************************************************
+*
+*   raylib [textures] example - Image processing
+*
+*   NOTE: Images are loaded in CPU memory (RAM); textures are loaded in GPU memory (VRAM)
+*
+*   This example has been created using raylib 3.5 (www.raylib.com)
+*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
+*
+*   Copyright (c) 2016 Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+#include <stdlib.h>             // Required for: free()
+
+#define NUM_PROCESSES    8
+
+typedef enum {
+    NONE = 0,
+    COLOR_GRAYSCALE,
+    COLOR_TINT,
+    COLOR_INVERT,
+    COLOR_CONTRAST,
+    COLOR_BRIGHTNESS,
+    FLIP_VERTICAL,
+    FLIP_HORIZONTAL
+} ImageProcess;
+
+static const char *processText[] = {
+    "NO PROCESSING",
+    "COLOR GRAYSCALE",
+    "COLOR TINT",
+    "COLOR INVERT",
+    "COLOR CONTRAST",
+    "COLOR BRIGHTNESS",
+    "FLIP VERTICAL",
+    "FLIP HORIZONTAL"
+};
+
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 450;
+
+    InitWindow(screenWidth, screenHeight, "raylib [textures] example - image processing");
+
+    // NOTE: Textures MUST be loaded after Window initialization (OpenGL context is required)
+
+    Image imOrigin = LoadImage("resources/parrots.png");   // Loaded in CPU memory (RAM)
+    ImageFormat(&imOrigin, PIXELFORMAT_UNCOMPRESSED_R8G8B8A8);         // Format image to RGBA 32bit (required for texture update) <-- ISSUE
+    Texture2D texture = LoadTextureFromImage(imOrigin);    // Image converted to texture, GPU memory (VRAM)
+
+    Image imCopy = ImageCopy(imOrigin);
+
+    int currentProcess = NONE;
+    bool textureReload = false;
+
+    Rectangle toggleRecs[NUM_PROCESSES] = { 0 };
+    int mouseHoverRec = -1;
+
+    for (int i = 0; i < NUM_PROCESSES; i++) toggleRecs[i] = (Rectangle){ 40.0f, (float)(50 + 32*i), 150.0f, 30.0f };
+
+    SetTargetFPS(60);
+    //---------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+
+        // Mouse toggle group logic
+        for (int i = 0; i < NUM_PROCESSES; i++)
+        {
+            if (CheckCollisionPointRec(GetMousePosition(), toggleRecs[i]))
+            {
+                mouseHoverRec = i;
+
+                if (IsMouseButtonReleased(MOUSE_BUTTON_LEFT))
+                {
+                    currentProcess = i;
+                    textureReload = true;
+                }
+                break;
+            }
+            else mouseHoverRec = -1;
+        }
+
+        // Keyboard toggle group logic
+        if (IsKeyPressed(KEY_DOWN))
+        {
+            currentProcess++;
+            if (currentProcess > (NUM_PROCESSES - 1)) currentProcess = 0;
+            textureReload = true;
+        }
+        else if (IsKeyPressed(KEY_UP))
+        {
+            currentProcess--;
+            if (currentProcess < 0) currentProcess = 7;
+            textureReload = true;
+        }
+
+        // Reload texture when required
+        if (textureReload)
+        {
+            UnloadImage(imCopy);                // Unload image-copy data
+            imCopy = ImageCopy(imOrigin);     // Restore image-copy from image-origin
+
+            // NOTE: Image processing is a costly CPU process to be done every frame,
+            // If image processing is required in a frame-basis, it should be done
+            // with a texture and by shaders
+            switch (currentProcess)
+            {
+                case COLOR_GRAYSCALE: ImageColorGrayscale(&imCopy); break;
+                case COLOR_TINT: ImageColorTint(&imCopy, GREEN); break;
+                case COLOR_INVERT: ImageColorInvert(&imCopy); break;
+                case COLOR_CONTRAST: ImageColorContrast(&imCopy, -40); break;
+                case COLOR_BRIGHTNESS: ImageColorBrightness(&imCopy, -80); break;
+                case FLIP_VERTICAL: ImageFlipVertical(&imCopy); break;
+                case FLIP_HORIZONTAL: ImageFlipHorizontal(&imCopy); break;
+                default: break;
+            }
+
+            Color *pixels = LoadImageColors(imCopy);    // Load pixel data from image (RGBA 32bit)
+            UpdateTexture(texture, pixels);             // Update texture with new image data
+            UnloadImageColors(pixels);                  // Unload pixels data from RAM
+
+            textureReload = false;
+        }
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(RAYWHITE);
+
+            DrawText("IMAGE PROCESSING:", 40, 30, 10, DARKGRAY);
+
+            // Draw rectangles
+            for (int i = 0; i < NUM_PROCESSES; i++)
+            {
+                DrawRectangleRec(toggleRecs[i], ((i == currentProcess) || (i == mouseHoverRec)) ? SKYBLUE : LIGHTGRAY);
+                DrawRectangleLines((int)toggleRecs[i].x, (int) toggleRecs[i].y, (int) toggleRecs[i].width, (int) toggleRecs[i].height, ((i == currentProcess) || (i == mouseHoverRec)) ? BLUE : GRAY);
+                DrawText( processText[i], (int)( toggleRecs[i].x + toggleRecs[i].width/2 - MeasureText(processText[i], 10)/2), (int) toggleRecs[i].y + 11, 10, ((i == currentProcess) || (i == mouseHoverRec)) ? DARKBLUE : DARKGRAY);
+            }
+
+            DrawTexture(texture, screenWidth - texture.width - 60, screenHeight/2 - texture.height/2, WHITE);
+            DrawRectangleLines(screenWidth - texture.width - 60, screenHeight/2 - texture.height/2, texture.width, texture.height, BLACK);
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    UnloadTexture(texture);       // Unload texture from VRAM
+    UnloadImage(imOrigin);        // Unload image-origin from RAM
+    UnloadImage(imCopy);          // Unload image-copy from RAM
+
+    CloseWindow();                // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}