Added Blend Modes example. (#1261)

examples/textures/textures_blend_modes.c

@@ -0,0 +1,100 @@
+/*******************************************************************************************
+*
+*   raylib [textures] example - blend modes
+*
+*   NOTE: Images are loaded in CPU memory (RAM); textures are loaded in GPU memory (VRAM)
+*
+*   This example has been created using raylib 3.0 (www.raylib.com)
+*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
+*
+*   Copyright (c) 2020 Karlo Licudine (@accidentalrebel)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+int main(void)
+{
+	// Initialization
+	//--------------------------------------------------------------------------------------
+	const int screenWidth = 800;
+	const int screenHeight = 450;
+
+	InitWindow(screenWidth, screenHeight, "raylib [textures] example - blend modes");
+
+	// NOTE: Textures MUST be loaded after Window initialization (OpenGL context is required)
+	Image bgImage = LoadImage("resources/cyberpunk_street_background.png");     // Loaded in CPU memory (RAM)
+	Texture2D bgTexture = LoadTextureFromImage(bgImage);          // Image converted to texture, GPU memory (VRAM)
+
+	Image fgImage = LoadImage("resources/cyberpunk_street_foreground.png");     // Loaded in CPU memory (RAM)
+	Texture2D fgTexture = LoadTextureFromImage(fgImage);          // Image converted to texture, GPU memory (VRAM)
+
+	// Once image has been converted to texture and uploaded to VRAM, it can be unloaded from RAM
+	UnloadImage(bgImage);   
+	UnloadImage(fgImage);
+
+	const int blendCountMax = 4;
+	BlendMode blendMode = 0;
+	
+	// Main game loop
+	while (!WindowShouldClose())    // Detect window close button or ESC key
+	{
+		// Update
+		//----------------------------------------------------------------------------------
+		int key = GetKeyPressed();
+		if ((key >= 32) && (key <= 126))
+		{
+			if ( blendMode >= blendCountMax - 1 )
+				blendMode = 0;
+			else
+				blendMode++;
+		}
+		
+		// Draw
+		//----------------------------------------------------------------------------------
+		BeginDrawing();
+
+		ClearBackground(RAYWHITE);
+
+		BeginBlendMode(BLEND_ALPHA);
+		DrawTexture(bgTexture, screenWidth/2 - bgTexture.width/2, screenHeight/2 - bgTexture.height/2, WHITE);
+
+		// Apply the blend mode and then draw the foreground texture
+		BeginBlendMode(blendMode);
+		DrawTexture(fgTexture, screenWidth/2 - fgTexture.width/2, screenHeight/2 - fgTexture.height/2, WHITE);
+
+		EndBlendMode();
+
+		// Draw the texts
+		DrawText("Press any key to change blend modes.", 310, 350, 10, GRAY);
+		switch ( blendMode )
+		{
+		 case BLEND_ALPHA:
+			 DrawText("Current: BLEND_ALPHA", (screenWidth / 2) - 60, 370, 10, GRAY);
+			 break;
+		 case BLEND_ADDITIVE:
+			 DrawText("Current: BLEND_ADDITIVE", (screenWidth / 2) - 60, 370, 10, GRAY);
+			 break;
+		 case BLEND_MULTIPLIED:
+			 DrawText("Current: BLEND_MULTIPLIED", (screenWidth / 2) - 60, 370, 10, GRAY);
+			 break;
+		 case BLEND_ADD_COLORS:
+			 DrawText("Current: BLEND_ADD_COLORS", (screenWidth / 2) - 60, 370, 10, GRAY);
+			 break;
+		}
+		DrawText("(c) Cyberpunk Street Environment by Luis Zuno (@ansimuz)", screenWidth - 330, screenHeight - 20, 10, GRAY);
+
+		EndDrawing();
+		//----------------------------------------------------------------------------------
+	}
+
+	// De-Initialization
+	//--------------------------------------------------------------------------------------
+	UnloadTexture(fgTexture); // Unload foreground texture
+	UnloadTexture(bgTexture); // Unload background texture
+
+	CloseWindow();            // Close window and OpenGL context
+	//--------------------------------------------------------------------------------------
+	
+	return 0;
+}