feat: finish ghostty pane backend integration

1 files changed, 121 insertions, 0 deletions

diff --git a/vendor/libghostty-vt/pkg/wuffs/src/swizzle.zig b/vendor/libghostty-vt/pkg/wuffs/src/swizzle.zig
new file mode 100644
index 00000000..352cf2b5
--- /dev/null
+++ b/vendor/libghostty-vt/pkg/wuffs/src/swizzle.zig
@@ -0,0 +1,121 @@
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+const assert = std.debug.assert;
+const c = @import("c.zig").c;
+const Error = @import("error.zig").Error;
+
+const log = std.log.scoped(.wuffs_swizzler);
+
+pub fn gToRgba(alloc: Allocator, src: []const u8) Error![]u8 {
+    return swizzle(
+        alloc,
+        src,
+        c.WUFFS_BASE__PIXEL_FORMAT__Y,
+        c.WUFFS_BASE__PIXEL_FORMAT__RGBA_PREMUL,
+    );
+}
+
+pub fn gaToRgba(alloc: Allocator, src: []const u8) Error![]u8 {
+    return swizzle(
+        alloc,
+        src,
+        c.WUFFS_BASE__PIXEL_FORMAT__YA_PREMUL,
+        c.WUFFS_BASE__PIXEL_FORMAT__RGBA_PREMUL,
+    );
+}
+
+pub fn rgbToRgba(alloc: Allocator, src: []const u8) Error![]u8 {
+    return swizzle(
+        alloc,
+        src,
+        c.WUFFS_BASE__PIXEL_FORMAT__RGB,
+        c.WUFFS_BASE__PIXEL_FORMAT__RGBA_PREMUL,
+    );
+}
+
+pub fn bgrToRgba(alloc: Allocator, src: []const u8) Error![]u8 {
+    return swizzle(
+        alloc,
+        src,
+        c.WUFFS_BASE__PIXEL_FORMAT__BGR,
+        c.WUFFS_BASE__PIXEL_FORMAT__RGBA_PREMUL,
+    );
+}
+
+pub fn bgraToRgba(alloc: Allocator, src: []const u8) Error![]u8 {
+    return swizzle(
+        alloc,
+        src,
+        c.WUFFS_BASE__PIXEL_FORMAT__BGRA_PREMUL,
+        c.WUFFS_BASE__PIXEL_FORMAT__RGBA_PREMUL,
+    );
+}
+
+fn swizzle(
+    alloc: Allocator,
+    src: []const u8,
+    comptime src_pixel_format: u32,
+    comptime dst_pixel_format: u32,
+) Error![]u8 {
+    const src_slice = c.wuffs_base__make_slice_u8(
+        @constCast(src.ptr),
+        src.len,
+    );
+
+    const dst_fmt = c.wuffs_base__make_pixel_format(
+        dst_pixel_format,
+    );
+
+    assert(c.wuffs_base__pixel_format__is_direct(&dst_fmt));
+    assert(c.wuffs_base__pixel_format__is_interleaved(&dst_fmt));
+    assert(c.wuffs_base__pixel_format__bits_per_pixel(&dst_fmt) % 8 == 0);
+
+    const dst_size = c.wuffs_base__pixel_format__bits_per_pixel(&dst_fmt) / 8;
+
+    const src_fmt = c.wuffs_base__make_pixel_format(
+        src_pixel_format,
+    );
+
+    assert(c.wuffs_base__pixel_format__is_direct(&src_fmt));
+    assert(c.wuffs_base__pixel_format__is_interleaved(&src_fmt));
+    assert(c.wuffs_base__pixel_format__bits_per_pixel(&src_fmt) % 8 == 0);
+
+    const src_size = c.wuffs_base__pixel_format__bits_per_pixel(&src_fmt) / 8;
+
+    assert(src.len % src_size == 0);
+
+    const dst = try alloc.alloc(u8, src.len * dst_size / src_size);
+    errdefer alloc.free(dst);
+
+    const dst_slice = c.wuffs_base__make_slice_u8(
+        dst.ptr,
+        dst.len,
+    );
+
+    var swizzler: c.wuffs_base__pixel_swizzler = undefined;
+    {
+        const status = c.wuffs_base__pixel_swizzler__prepare(
+            &swizzler,
+            dst_fmt,
+            c.wuffs_base__empty_slice_u8(),
+            src_fmt,
+            c.wuffs_base__empty_slice_u8(),
+            c.WUFFS_BASE__PIXEL_BLEND__SRC,
+        );
+        if (!c.wuffs_base__status__is_ok(&status)) {
+            const e = c.wuffs_base__status__message(&status);
+            log.warn("{s}", .{e});
+            return error.WuffsError;
+        }
+    }
+    {
+        _ = c.wuffs_base__pixel_swizzler__swizzle_interleaved_from_slice(
+            &swizzler,
+            dst_slice,
+            c.wuffs_base__empty_slice_u8(),
+            src_slice,
+        );
+    }
+
+    return dst;
+}