Add core_highdpi example

This example enables HIGHDPI and renders a scale showing how the logical
size compares to the pixel size of the window.

Author: marler8997

examples/Makefile

@@ -508,6 +508,7 @@ CORE = \
     core/core_custom_frame_control \
     core/core_custom_logging \
     core/core_drop_files \
+    core/core_highdpi \
     core/core_input_gamepad \
     core/core_input_gestures \
     core/core_input_gestures_web \

examples/Makefile.Web

@@ -390,6 +390,7 @@ CORE = \
     core/core_custom_frame_control \
     core/core_custom_logging \
     core/core_drop_files \
+    core/core_highdpi \
     core/core_input_gamepad \
     core/core_input_gestures \
     core/core_input_gestures_web \

examples/README.md

@@ -59,6 +59,7 @@ Examples using raylib core platform functionality like window creation, inputs,
 | 33 | [core_basic_window_web](core/core_basic_window_web.c) | <img src="core/core_basic_window_web.png" alt="core_basic_window_web" width="80"> | ⭐️☆☆☆ | 1.3 | 1.3 | [Ray](https://github.com/raysan5) |
 | 34 | [core_input_gestures_web](core/core_input_gestures_web.c) | <img src="core/core_input_gestures_web.png" alt="core_input_gestures_web" width="80"> | ⭐️⭐️☆☆ | 4.6-dev | 4.6-dev | [ubkp](https://github.com/ubkp) |
 | 35 | [core_automation_events](core/core_automation_events.c) | <img src="core/core_automation_events.png" alt="core_automation_events" width="80"> | ⭐️⭐️⭐️☆ | 5.0 | 5.0 | [Ray](https://github.com/raysan5) |
+| 36 | [core_highdpi](core/core_highdpi.c) | <img src="core/core_highdpi.png" alt="core_highdpi" width="80"> | ⭐️☆☆☆ | 5.0 | 5.0 | [Jonathan Marler](https://github.com/marler8997) |
 
 ### category: shapes
 

examples/core/core_highdpi.c

@@ -0,0 +1,119 @@
+/*******************************************************************************************
+*
+*   raylib [core] example - HighDPI
+*
+*   Example complexity rating: [★☆☆☆] e/4
+*
+*   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) 2013-2025 Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+static void DrawTextCenter(const char *text, int x, int y, int fontSize, Color color)
+{
+    Vector2 size = MeasureTextEx(GetFontDefault(), text, fontSize, 3);
+    Vector2 pos = (Vector2){x - size.x/2, y - size.y/2 };
+    DrawTextEx(GetFontDefault(), text, pos, fontSize, 3, color);
+}
+
+//------------------------------------------------------------------------------------
+// Program main entry point
+//------------------------------------------------------------------------------------
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 450;
+
+    SetConfigFlags(FLAG_WINDOW_HIGHDPI | FLAG_WINDOW_RESIZABLE);
+
+    InitWindow(screenWidth, screenHeight, "raylib [core] example - highdpi");
+    SetWindowMinSize(450, 450);
+
+    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
+        //----------------------------------------------------------------------------------
+        int monitorCount = GetMonitorCount();
+        if (monitorCount > 1 && IsKeyPressed(KEY_N)) {
+            SetWindowMonitor((GetCurrentMonitor() + 1) % monitorCount);
+        }
+        int currentMonitor = GetCurrentMonitor();
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            Vector2 dpiScale = GetWindowScaleDPI();
+            ClearBackground(RAYWHITE);
+
+            int windowCenter = GetScreenWidth() / 2;
+            DrawTextCenter(TextFormat("Dpi Scale: %f", dpiScale.x), windowCenter, 30, 40, DARKGRAY);
+            DrawTextCenter(TextFormat("Monitor: %d/%d ([N] next monitor)", currentMonitor+1, monitorCount), windowCenter, 70, 16, LIGHTGRAY);
+
+            const int logicalGridDescY = 120;
+            const int logicalGridLabelY = logicalGridDescY + 30;
+            const int logicalGridTop = logicalGridLabelY + 30;
+            const int logicalGridBottom = logicalGridTop + 80;
+            const int pixelGridTop = logicalGridBottom - 20;
+            const int pixelGridBottom = pixelGridTop + 80;
+            const int pixelGridLabelY = pixelGridBottom + 30;
+            const int pixelGridDescY = pixelGridLabelY + 30;
+
+            const int cellSize = 50;
+            const float cellSizePx = ((float)cellSize) / dpiScale.x;
+
+            DrawTextCenter(TextFormat("Window is %d \"logical points\" wide", GetScreenWidth()), windowCenter, logicalGridDescY, 20, ORANGE);
+            bool odd = true;
+            for (int i = cellSize; i < GetScreenWidth(); i += cellSize, odd = !odd) {
+                if (odd) {
+                    DrawRectangle(i, logicalGridTop, cellSize, logicalGridBottom-logicalGridTop, ORANGE);
+                }
+                DrawTextCenter(TextFormat("%d", i), i, logicalGridLabelY, 12, LIGHTGRAY);
+                DrawLine(i, logicalGridLabelY + 10, i, logicalGridBottom, GRAY);
+            }
+
+            odd = true;
+            const int minTextSpace = 30;
+            int last_text_x = -minTextSpace;
+            for (int i = cellSize; i < GetRenderWidth(); i += cellSize, odd = !odd) {
+                int x = ((float)i) / dpiScale.x;
+                if (odd) {
+                    DrawRectangle(x, pixelGridTop, cellSizePx, pixelGridBottom-pixelGridTop, CLITERAL(Color){ 0, 121, 241, 100 });
+                }
+                DrawLine(x, pixelGridTop, ((float)i) / dpiScale.x, pixelGridLabelY - 10, GRAY);
+                if (x - last_text_x >= minTextSpace) {
+                    DrawTextCenter(TextFormat("%d", i), x, pixelGridLabelY, 12, LIGHTGRAY);
+                    last_text_x = x;
+                }
+            }
+
+            DrawTextCenter(TextFormat("Window is %d \"physical pixels\" wide", GetRenderWidth()), windowCenter, pixelGridDescY, 20, BLUE);
+
+            {
+                const char *text = "Can you see this?";
+                Vector2 size = MeasureTextEx(GetFontDefault(), text, 16, 3);
+                Vector2 pos = (Vector2){GetScreenWidth() - size.x - 5, GetScreenHeight() - size.y - 5};
+                DrawTextEx(GetFontDefault(), text, pos, 16, 3, LIGHTGRAY);
+            }
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}