From 7fdc7a9dfcb7e66c68b760bffac1045d595620c3 Mon Sep 17 00:00:00 2001
From: Louis Pearson <opensource@louispearson.work>
Date: Fri, 16 Feb 2024 17:58:42 -0700
Subject: [PATCH] feat: add mach-freetype, render a glyph

---
 build.zig     | 10 ++++++++++
 build.zig.zon | 15 +++++++++++++++
 src/main.zig  | 42 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 67 insertions(+)
 create mode 100644 build.zig.zon

diff --git a/build.zig b/build.zig
index 121a518..c6673a5 100644
--- a/build.zig
+++ b/build.zig
@@ -24,5 +24,15 @@ pub fn build(b: *std.Build) void {
 
     exe.addIncludePath(.{ .path = "deps/font8x8/" });
 
+    const mach_freetype_dep = b.dependency("mach_freetype", .{
+        .target = target,
+        .optimize = optimize,
+    });
+    exe.root_module.addImport("freetype", mach_freetype_dep.module("mach-freetype"));
+    exe.root_module.addImport("harfbuzz", mach_freetype_dep.module("mach-harfbuzz"));
+
+    const font_assets_dep = b.dependency("font_assets", .{});
+    exe.root_module.addImport("font-assets", font_assets_dep.module("font-assets"));
+
     b.installArtifact(exe);
 }
diff --git a/build.zig.zon b/build.zig.zon
new file mode 100644
index 0000000..5084e3b
--- /dev/null
+++ b/build.zig.zon
@@ -0,0 +1,15 @@
+.{
+    .name = "pinephone-test",
+    .version = "0.0.0",
+    .paths = .{""},
+    .dependencies = .{
+        .mach_freetype = .{
+            .url = "https://pkg.machengine.org/mach-freetype/dc4a5d8ce14f8678f35bdaf197303091e22b1f27.tar.gz",
+            .hash = "122070070dd2c402d94c279d64d4a4d154691ad49f46fa2c24ed7c6e4e4f5c531477",
+        },
+        .font_assets = .{
+            .url = "https://pkg.machengine.org/font-assets/6b43c160451e8fa5c64620ffb614929feacf2f5d.tar.gz",
+            .hash = "12202039304f0603a9706105788e450fd4f901c3e20eca28a52a2173879b14c606c7",
+        },
+    },
+}
diff --git a/src/main.zig b/src/main.zig
index a805968..b627f14 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -1,5 +1,7 @@
 const std = @import("std");
 const wayland = @import("root.zig");
+const freetype = @import("freetype");
+const font_assets = @import("font-assets");
 
 const Conn = wayland.Conn;
 const Context = wayland.Context(&.{
@@ -63,6 +65,12 @@ pub fn main() !void {
     var conn = try Conn.init(gpa, display_path);
     defer conn.deinit();
 
+    const freetype_lib = try freetype.Library.init();
+    defer freetype_lib.deinit();
+
+    const face = try freetype_lib.createFaceMemory(font_assets.fira_sans_regular_ttf, 0);
+    try face.setCharSize(60 * 48, 0, 50, 0);
+
     // Register all globals
     var ctx = try Context.init(&conn);
 
@@ -85,6 +93,8 @@ pub fn main() !void {
         .ctx = &ctx,
         .ally = gpa,
         .callbacks = std.AutoHashMap(u32, App.Callback).init(gpa),
+        .freetype_lib = freetype_lib,
+        .font_face = face,
         .state = .{ .init = .{} },
         .display = display,
         .shm = shm,
@@ -154,6 +164,8 @@ const App = struct {
     ctx: *Context,
     ally: std.mem.Allocator,
     callbacks: std.AutoHashMap(u32, Callback),
+    freetype_lib: freetype.Library,
+    font_face: freetype.Face,
 
     display: wayland.core.Display,
     shm: wayland.core.Shm,
@@ -438,6 +450,33 @@ const Canvas = struct {
             }
         }
     }
+
+    fn blitFreetypeBitmap(canvas: Canvas, bitmap: freetype.Bitmap, pos: [2]u32) void {
+        const fb = canvas.fb;
+        const width = canvas.size[0];
+        const height = canvas.size[1];
+        const rows = bitmap.rows();
+        const cols = bitmap.width();
+        const left = pos[0];
+        const top = pos[1];
+        const right = @min(left + cols, width);
+        const bottom = @min(top + rows, height);
+        const buffer = bitmap.buffer().?;
+        if (pos[0] > width or pos[1] > height) return;
+        for (top..bottom, 0..) |y, i| {
+            const row = fb[y * width .. (y + 1) * width];
+            for (left..right, 0..) |x, a| {
+                const pixel = &row[x];
+                const intensity = buffer[i * cols + a];
+                pixel.* = .{
+                    intensity,
+                    intensity,
+                    intensity,
+                    0xFF,
+                };
+            }
+        }
+    }
 };
 
 fn wmbaseHandler(app: *App, header: wayland.Header, body: []const u32) !void {
@@ -484,7 +523,10 @@ fn surfaceDesktopHandler(app: *App, header: wayland.Header, body: []const u32) !
 
             // render
             const canvas = try pool.getFramebuffer(.{ width, height });
+            try app.font_face.loadChar('H', .{ .render = true });
+            const bitmap = app.font_face.glyph().bitmap();
             canvas.renderGradient();
+            canvas.blitFreetypeBitmap(bitmap, .{ 0, 0 });
             try canvas.attach(app.surface);
             try app.callbacks.put(canvas.buffer.id, bufferHandler);
         },