[examples] Added `core_clipboard_text` (#5231)

* added clipboard example

* added image check

* added note about windows

* added indent

examples/core/core_clipboard_text.c

@@ -0,0 +1,208 @@
+/*******************************************************************************************
+*
+*   raylib [core] example - clipboard text
+*
+*   Example complexity rating: [★☆☆☆] 1/4
+*
+*   Example originally created with raylib 5.6-dev
+*
+*   Example contributed by Robin (@RobinsAviary) 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 Robin (@RobinsAviary)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+#include <stdio.h>
+
+//------------------------------------------------------------------------------------
+// Program main entry point
+//------------------------------------------------------------------------------------
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 450;
+
+    InitWindow(screenWidth, screenHeight, "raylib [core] example - clipboard text");
+
+    const char* clipboardText = NULL;
+
+    // List of text the user can switch through and copy
+    const char* copyableText[] = {"raylib is fun", "hello, clipboard!", "potato chips"};
+
+    unsigned int textIndex = 0;
+
+    const char* popupText = NULL;
+
+    // Initialize timers
+    // The amount of time the pop-up text is on screen, before fading
+    const float maxTime = 3.0f;
+    float textTimer = 0.0f;
+    // The length of time text is offset
+    const float animMaxTime = 0.1f;
+    float pasteAnim = 0.0f;
+    float copyAnim = 0.0f;
+    int copyAnimMult = 1;
+    float textAnim = 0.0f;
+    float textAlpha = 0.0f;
+    // Offset amount for animations
+    const int offsetAmount = -4;
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        // Check if the user has pressed the copy/paste key combinations
+        bool pastePressed = (IsKeyDown(KEY_LEFT_CONTROL) && IsKeyPressed(KEY_V));
+        bool copyPressed = (IsKeyDown(KEY_LEFT_CONTROL) && IsKeyPressed(KEY_C));
+
+        // Update animation timers
+        if (textTimer > 0) textTimer -= GetFrameTime();
+        if (pasteAnim > 0) pasteAnim -= GetFrameTime();
+        if (copyAnim > 0) copyAnim -= GetFrameTime();
+        if (textAnim > 0) textAnim -= GetFrameTime();
+
+        // React to the user pressing paste
+        if (pastePressed)
+        {
+            // Most operating systems hide this information until the user presses Ctrl-V on the window.
+
+            // Check to see if the clipboard contains an image
+            // This function does nothing outside of Windows, as it directly calls the Windows API
+            Image image = GetClipboardImage();
+            
+            if (IsImageValid(image))
+            {
+                // Unload the image
+                UnloadImage(image);
+                // Update visuals
+                popupText = "clipboard contains image";
+            }
+            else
+            {
+                // Get text from the user's clipboard
+                clipboardText = GetClipboardText();
+                
+                // Update visuals
+                popupText = "text pasted";
+                pasteAnim = animMaxTime;
+            }
+
+            // Reset animation values
+            textTimer = maxTime;
+            textAnim = animMaxTime;
+            textAlpha = 1;
+        }
+
+        // React to the user pressing copy
+        if (copyPressed)
+        {
+            // Set the text on the user's clipboard
+            SetClipboardText(copyableText[textIndex]);
+
+            // Reset values
+            textTimer = maxTime;
+            textAnim = animMaxTime;
+            copyAnim = animMaxTime;
+            copyAnimMult = 1;
+            textAlpha = 1;
+            // Update the text that pops up at the bottom of the screen
+            popupText = "text copied";
+        }
+
+        // Switch to the next item in the list when the user presses up
+        if (IsKeyPressed(KEY_UP))
+        {
+            // Reset animation
+            copyAnim = animMaxTime;
+            copyAnimMult = 1;
+
+            textIndex += 1;
+
+            if (textIndex >= sizeof(copyableText) / sizeof(const char*)) // Length of array
+            { 
+                // Loop back to the other end
+                textIndex = 0;
+            }
+        }
+
+        // Switch to the previous item in the list when the user presses down
+        if (IsKeyPressed(KEY_DOWN))
+        {
+            // Reset animation
+            copyAnim = animMaxTime;
+            copyAnimMult = -1;
+
+            if (textIndex == 0)
+            {
+                // Loop back to the other end
+                textIndex = (sizeof(copyableText) / sizeof(const char*)) - 1; // Length of array minus one
+            } 
+            else
+            {
+                textIndex -= 1;
+            }
+        }
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+			ClearBackground(RAYWHITE);
+
+			// Draw the user's pasted text, if there is any yet
+			if (clipboardText)
+			{
+				// Offset animation
+				int offset = 0;
+				if (pasteAnim > 0) offset = offsetAmount;
+
+				// Draw the pasted text
+				DrawText("pasted clipboard:", 10, 10 + offset, 20, DARKGREEN);
+				DrawText(clipboardText, 10, 30 + offset, 20, DARKGRAY);
+			}
+
+			// Offset animation
+			int textOffset = 0;
+			if (copyAnim > 0) textOffset = offsetAmount;
+
+			// Draw copyable text and controls
+			DrawText(copyableText[textIndex], 10, 330 + (textOffset * copyAnimMult), 20, MAROON);
+			DrawText("up/down to change string, ctrl-c to copy, ctrl-v to paste", 10, 355, 20, DARKGRAY);
+
+			// Alpha / Offset animation
+			if (textAlpha > 0)
+			{
+				// Offset animation
+				int offset = 0;
+				if (textAnim > 0) offset = offsetAmount;
+				// Draw pop up text
+				DrawText(popupText, 10, 425 + offset, 20, ColorAlpha(DARKGREEN, textAlpha));
+
+				// Fade-out animation
+				if (textTimer < 0)
+				{
+					textAlpha -= GetFrameTime();
+				}
+			}
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}