[examples] Add core_monitor_change (#5215)

* Add core monitor change example

* Add monitor drawing and more information

* Update monitor information every frame

* Show info and window position inside the rectangle

Author: maiconpintoabreu

examples/core/core_monitor_change.c

@@ -0,0 +1,170 @@
+/*******************************************************************************************
+*
+*   raylib [core] example - monitor change
+*
+*   Example complexity rating: [★☆☆☆] 1/4
+*
+*   Example originally created with raylib 5.5, last time updated with raylib 5.6
+*
+*   Example contributed by Maicon Santana (@maiconpintoabreu) 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) 2025-2025 Maicon Santana (@maiconpintoabreu)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+#define MAX_MONITORS 10
+
+// Monitor Details
+typedef struct Monitor {
+    Vector2 position;
+    char *name;
+    int width;
+    int height;
+    int physicalWidth;
+    int physicalHeight;
+    int refreshRate;
+} Monitor;
+
+//------------------------------------------------------------------------------------
+// Program main entry point
+//------------------------------------------------------------------------------------
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 450;
+
+    Monitor monitors[MAX_MONITORS] = { 0 };
+
+    InitWindow(screenWidth, screenHeight, "raylib [core] example - monitor change");
+
+    int currentMonitorIndex = GetCurrentMonitor();
+    int monitorCount = 0;
+
+    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
+        //----------------------------------------------------------------------------------
+
+        // Variables to find the max x and Y to calculate the scale
+        int maxWidth = 1;
+        int maxHeight = 1;
+
+        // Monitor offset is to fix when monitor position x is negative
+        int monitorOffsetX = 0;
+
+        // Rebuild monitors array every frame
+        monitorCount = GetMonitorCount();
+        for (int i = 0; i < monitorCount; i++)
+        {
+            monitors[i] = (Monitor){
+                GetMonitorPosition(i), 
+                GetMonitorName(i), 
+                GetMonitorWidth(i),
+                GetMonitorHeight(i),
+                GetMonitorPhysicalWidth(i),
+                GetMonitorPhysicalHeight(i),
+                GetMonitorRefreshRate(i)
+            };
+            if (monitors[i].position.x < monitorOffsetX) monitorOffsetX = monitors[i].position.x*-1;
+
+            const int width = monitors[i].position.x + monitors[i].width;
+            const int height = monitors[i].position.y + monitors[i].height;
+            
+            if (maxWidth < width) maxWidth = width;
+            if (maxHeight < height) maxHeight = height;
+        }
+
+        if (IsKeyPressed(KEY_ENTER) && monitorCount > 1) 
+        {
+            currentMonitorIndex += 1;
+
+            // Set index to 0 if the last one
+            if(currentMonitorIndex == monitorCount) currentMonitorIndex = 0;
+
+            SetWindowMonitor(currentMonitorIndex); // Move window to currentMonitorIndex
+        }
+        else 
+        {
+            // Get currentMonitorIndex if manually moved
+            currentMonitorIndex = GetCurrentMonitor();
+        }
+        const Monitor currentMonitor = monitors[currentMonitorIndex];
+
+        float monitorScale = 0.6; 
+
+        if(maxHeight > maxWidth + monitorOffsetX) monitorScale *= ((float)screenHeight/(float)maxHeight);
+        else monitorScale *= ((float)screenWidth/(float)(maxWidth + monitorOffsetX));
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(RAYWHITE);
+
+            DrawText("Press [Enter] to move window to next monitor available", 20, 20, 20, DARKGRAY);
+
+            DrawRectangleLines(20, 60, screenWidth - 40, screenHeight - 100, DARKGRAY);
+
+            // Draw Monitor Rectangles with information inside
+            for (int i = 0; i < monitorCount; i++)
+            {
+                // Calculate retangle position and size using monitorScale
+                const Rectangle rec = (Rectangle){
+                    (monitors[i].position.x + monitorOffsetX) * monitorScale + 140,
+                    monitors[i].position.y * monitorScale + 80,
+                    monitors[i].width * monitorScale,
+                    monitors[i].height * monitorScale
+                };
+
+                // Draw monitor name and information inside the rectangle
+                DrawText(TextFormat("[%i] %s", i, monitors[i].name), rec.x + 10, rec.y + (int)(100*monitorScale), (int)(120*monitorScale), BLUE);
+                DrawText(
+                    TextFormat("Resolution: [%ipx x %ipx]\nRefreshRate: [%ihz]\nPhysical Size: [%imm x %imm]\nPosition: %3.0f x %3.0f", 
+                        monitors[i].width, 
+                        monitors[i].height, 
+                        monitors[i].refreshRate,
+                        monitors[i].physicalWidth,
+                        monitors[i].physicalHeight,
+                        monitors[i].position.x,
+                        monitors[i].position.y
+                    ), rec.x + 10, rec.y + (int)(200*monitorScale), (int)(120*monitorScale), DARKGRAY);
+
+                // Highlight current monitor
+                if (i == currentMonitorIndex)
+                {
+                    DrawRectangleLinesEx(rec, 5, RED);
+                    Vector2 windowPosition = (Vector2){ (GetWindowPosition().x + monitorOffsetX)*monitorScale  + 140, GetWindowPosition().y*monitorScale + 80 };
+
+                    // Draw window position based on monitors
+                    DrawRectangleV(windowPosition, (Vector2){screenWidth * monitorScale, screenHeight * monitorScale}, Fade(GREEN, 0.5));
+                }
+                else
+                {
+                    DrawRectangleLinesEx(rec, 5, GRAY);
+                }
+
+            }
+
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}