example: add codepoints_loading

update c_l to include copywrite header and description

build.zig

@@ -294,6 +294,11 @@ pub fn build(b: *std.Build) !void {
             .path = "examples/textures/textures_background_scrolling.zig",
             .desc = "Background scrolling & parallax demo",
         },
+        .{
+            .name = "codepoints_loading",
+            .path = "examples/text/codepoints_loading.zig",
+            .desc = "Renders UTF-8 text",
+        },
         .{
             .name = "text_format_text",
             .path = "examples/text/text_format_text.zig",

examples/text/codepoints_loading.zig

@@ -0,0 +1,166 @@
+//!******************************************************************************************
+//!
+//!   raylib-zog port of the [text] example - Codepoints loading
+//!   https://github.com/raysan5/raylib/blob/master/examples/text/text_codepoints_loading.c
+//!
+//!   Example complexity rating: [★★★☆] 3/4
+//!
+//!   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
+//!
+//!   Translated to raylib-zig by Timothy Fiss (@TheFissk)
+//!
+//!   Copyright (c) 2022-2025 Ramon Santamaria (@raysan5)
+//!
+//!*******************************************************************************************
+
+const rl = @import("raylib");
+const std = @import("std");
+
+/// 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
+const 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";
+
+// Remove codepoint duplicates if requested
+// static int *CodepointRemoveDuplicates(int *codepoints, int codepointCount, int *codepointResultCount);
+
+//------------------------------------------------------------------------------------
+// Program main entry point
+//------------------------------------------------------------------------------------
+pub fn main() anyerror!void {
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const screen_width = 800;
+    const screen_height = 450;
+
+    rl.initWindow(screen_width, screen_height, "raylib [text] example - codepoints loading");
+    defer rl.closeWindow(); // Close window and OpenGL context
+
+    // Convert each utf-8 character into its
+    // corresponding codepoint in the font file.
+    const codepoints = try rl.loadCodepoints(text);
+    const codepoints_count = codepoints.len;
+
+    //the DebugAllocator provides us with a nice general purpose allocator, great for small projects like this
+    var font: rl.Font = undefined;
+    var codepoints_no_dups: [:0]i32 = undefined;
+    var codepoints_no_dups_count: usize = undefined;
+    {
+        var dba = std.heap.DebugAllocator(.{}){};
+        var alloc = dba.allocator();
+        // Removed duplicate codepoints to generate smaller font atlas
+        codepoints_no_dups = try CodepointRemoveDuplicates(alloc, codepoints);
+        codepoints_no_dups_count = std.mem.len(codepoints_no_dups.ptr);
+        defer alloc.free(codepoints_no_dups);
+        // we can free codepoints at the end of this block, atlas has already been generated
+        rl.unloadCodepoints(codepoints);
+
+        // Load font containing all the provided codepoint glyphs
+        // A texture font atlas is automatically generated
+        // example assumes it is being run from the root of the project
+        font = try rl.loadFontEx("examples/text/resources/DotGothic16-Regular.ttf", 36, codepoints_no_dups);
+
+        // Set bilinear scale filter for better font scaling
+        rl.setTextureFilter(font.texture, .bilinear);
+        rl.setTextLineSpacing(20); // Set line spacing for multiline text (when line breaks are included '\n')
+    }
+    defer rl.unloadFont(font); // Unload font at the end of the program
+
+    var show_font_atlas = false;
+
+    var codepoint_size: i32 = 0;
+    var start: i32 = 0;
+
+    rl.setTargetFPS(60); // Set our game to run at 60 frames-per-second
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!rl.windowShouldClose()) // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        if (rl.isKeyPressed(.space)) show_font_atlas = !show_font_atlas;
+
+        // Testing code: getting next and previous codepoints on provided text
+        if (rl.isKeyPressed(.right)) {
+            // Get next codepoint in string and move pointer
+            const err = rl.getCodepointNext(text[@intCast(start)..text.len], &codepoint_size);
+            if (err == '?') @panic("getCodepointNext failed");
+            if (start + codepoint_size < text.len) {
+                start += codepoint_size;
+            } else {
+                start = text.len;
+            }
+        } else if (rl.isKeyPressed(.left)) {
+            // Get previous codepoint in string and move pointer
+            const err = rl.getCodepointPrevious(text[@intCast(start)..text.len], &codepoint_size);
+            if (err == '?') @panic("getCodepointNext failed");
+            if (start - codepoint_size > 0) {
+                start -= codepoint_size;
+            } else {
+                start = 0;
+            }
+        }
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        rl.beginDrawing();
+        defer rl.endDrawing();
+        rl.clearBackground(.ray_white);
+
+        rl.drawRectangle(0, 0, rl.getScreenWidth(), 70, .black);
+        rl.drawText(rl.textFormat("Total codepoints contained in provided text: %i", .{codepoints_count}), 10, 10, 20, .green);
+        rl.drawText(rl.textFormat("Total codepoints required for font atlas (duplicates excluded): %u", .{codepoints_no_dups_count}), 10, 40, 20, .green);
+
+        if (show_font_atlas) {
+            // Draw generated font texture atlas containing provided codepoints
+            rl.drawTexture(font.texture, 150, 100, .black);
+            rl.drawRectangleLines(150, 100, font.texture.width, font.texture.height, .black);
+        } else {
+            // Draw provided text with loaded font, containing all required codepoint glyphs
+            rl.drawTextEx(font, text, .{ .x = 160, .y = 110 }, 48, 5, .black);
+        }
+
+        rl.drawText("Press SPACE to toggle font atlas view!", 10, rl.getScreenHeight() - 30, 20, .gray);
+
+        //----------------------------------------------------------------------------------
+    }
+}
+
+/// Remove codepoint duplicates if requested
+/// WARNING: This process could be a bit slow if there text to process is very long
+fn CodepointRemoveDuplicates(allocator: std.mem.Allocator, codepoints: []i32) ![:0]i32 {
+    var no_dups: [:0]i32 = try allocator.allocSentinel(i32, codepoints.len, 0);
+    std.mem.copyForwards(i32, no_dups, codepoints);
+
+    var no_dups_count: usize = no_dups.len;
+
+    // Remove duplicates
+    var i: usize = 0;
+    while (i < no_dups_count) {
+        defer i += 1;
+        var j: usize = i + 1;
+        while (j < no_dups_count) {
+            defer j += 1;
+            const match = no_dups[i] == no_dups[j];
+            if (match) {
+                var k: usize = j;
+                while (k < no_dups_count) {
+                    defer k += 1;
+                    no_dups[k] = no_dups[k + 1];
+                }
+                no_dups_count -= 1;
+                j -= 1;
+                no_dups[no_dups_count] = 0;
+            }
+        }
+    }
+
+    // NOTE: The size of codepointsNoDups is the same as original array but
+    // only required positions are filled (codepointsNoDupsCount)
+    return no_dups;
+}