New example: text/codepoints_loading

examples/text/codepoints_loading/main.go

@@ -0,0 +1,108 @@
+/*******************************************************************************************
+*
+*   raylib [text] example - Codepoints loading
+*
+*   Example originally created with raylib 4.2, last time updated with raylib 2.5
+*
+*   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) 2022-2024 Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+package main
+
+import (
+	"fmt"
+
+	rl "github.com/gen2brain/raylib-go/raylib"
+)
+
+const (
+	screenWidth  = 800
+	screenHeight = 450
+)
+
+func main() {
+	rl.InitWindow(screenWidth, screenHeight, "raylib [text] example - codepoints loading")
+
+	// Text to be displayed, must be UTF-8 (save this code file as UTF-8)
+	// NOTE: It can contain all the required text for the game,
+	// this text will be scanned to get all the required codepoints
+	text := "いろはにほへと　ちりぬるを\nわかよたれそ　つねならむ\nうゐのおくやま　けふこえて\nあさきゆめみし　ゑひもせす"
+
+	// Get codepoints from text
+	allCodepoints := []rune(text)
+
+	// Removed duplicate codepoints to generate smaller font atlas
+	codepoints := CodepointRemoveDuplicates(allCodepoints)
+	codepointsCount := len(codepoints)
+
+	// Load font containing all the provided codepoint glyphs
+	// A texture font atlas is automatically generated
+	font := rl.LoadFontEx("resources/DotGothic16-Regular.ttf", 36, codepoints, int32(codepointsCount))
+
+	// Set bi-linear scale filter for better font scaling
+	rl.SetTextureFilter(font.Texture, rl.FilterBilinear)
+	// Set line spacing for multiline text (when line breaks are included '\n')
+	rl.SetTextLineSpacing(20)
+
+	showFontAtlas := false
+
+	rl.SetTargetFPS(60) // Set our game to run at 60 frames-per-second
+
+	// Main game loop
+	for !rl.WindowShouldClose() { // Detect window close button or ESC key
+		// Update
+		if rl.IsKeyPressed(rl.KeySpace) {
+			showFontAtlas = !showFontAtlas
+		}
+
+		// Draw
+		rl.BeginDrawing()
+		rl.ClearBackground(rl.RayWhite)
+
+		rl.DrawRectangle(0, 0, screenWidth, 70, rl.Black)
+		msg := fmt.Sprintf("Total codepoints contained in provided text: %d", len(allCodepoints))
+		rl.DrawText(msg, 10, 10, 20, rl.Green)
+		msg = fmt.Sprintf("Total codepoints required for font atlas (duplicates excluded): %d", codepointsCount)
+		rl.DrawText(msg, 10, 40, 20, rl.Green)
+
+		if showFontAtlas {
+			// Draw generated font texture atlas containing provided codepoints
+			rl.DrawTexture(font.Texture, 150, 100, rl.Black)
+			rl.DrawRectangleLines(150, 100, font.Texture.Width, font.Texture.Height, rl.Black)
+		} else {
+			// Draw provided text with loaded font, containing all required codepoint glyphs
+			pos := rl.Vector2{
+				X: 160,
+				Y: 110,
+			}
+			rl.DrawTextEx(font, text, pos, 48, 5, rl.Black)
+		}
+
+		msg = "Press SPACE to toggle font atlas view!"
+		rl.DrawText(msg, 10, screenHeight-30, 20, rl.Gray)
+
+		rl.EndDrawing()
+	}
+
+	// De-Initialization
+	rl.UnloadFont(font) // Unload font
+	rl.CloseWindow()    // Close window and OpenGL context
+}
+
+// CodepointRemoveDuplicates removes codepoint duplicates if requested
+func CodepointRemoveDuplicates[T comparable](sliceList []T) []T {
+	allKeys := make(map[T]bool)
+	var list []T
+
+	for _, item := range sliceList {
+		if _, value := allKeys[item]; !value {
+			allKeys[item] = true
+			list = append(list, item)
+		}
+	}
+
+	return list
+}