feat: finish ghostty pane backend integration

1 files changed, 108 insertions, 0 deletions

diff --git a/vendor/libghostty-vt/src/renderer/metal/Target.zig b/vendor/libghostty-vt/src/renderer/metal/Target.zig
new file mode 100644
index 00000000..f20bb0b7
--- /dev/null
+++ b/vendor/libghostty-vt/src/renderer/metal/Target.zig
@@ -0,0 +1,108 @@
+//! Represents a render target.
+//!
+//! In this case, an IOSurface-backed MTLTexture.
+const Self = @This();
+
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+const objc = @import("objc");
+const macos = @import("macos");
+const graphics = macos.graphics;
+const IOSurface = macos.iosurface.IOSurface;
+
+const mtl = @import("api.zig");
+
+const log = std.log.scoped(.metal);
+
+/// Options for initializing a Target
+pub const Options = struct {
+    /// MTLDevice
+    device: objc.Object,
+
+    /// Desired width
+    width: usize,
+    /// Desired height
+    height: usize,
+
+    /// Pixel format for the MTLTexture
+    pixel_format: mtl.MTLPixelFormat,
+    /// Storage mode for the MTLTexture
+    storage_mode: mtl.MTLResourceOptions.StorageMode,
+};
+
+/// The underlying IOSurface.
+surface: *IOSurface,
+
+/// The underlying MTLTexture.
+texture: objc.Object,
+
+/// Current width of this target.
+width: usize,
+/// Current height of this target.
+height: usize,
+
+pub fn init(opts: Options) !Self {
+    // We set our surface's color space to Display P3.
+    // This allows us to have "Apple-style" alpha blending,
+    // since it seems to be the case that Apple apps like
+    // Terminal and TextEdit render text in the display's
+    // color space using converted colors, which reduces,
+    // but does not fully eliminate blending artifacts.
+    const colorspace = try graphics.ColorSpace.createNamed(.displayP3);
+    defer colorspace.release();
+
+    const surface = try IOSurface.init(.{
+        .width = @intCast(opts.width),
+        .height = @intCast(opts.height),
+        .pixel_format = .@"32BGRA",
+        .bytes_per_element = 4,
+        .colorspace = colorspace,
+    });
+
+    // Create our descriptor
+    const desc = init: {
+        const Class = objc.getClass("MTLTextureDescriptor").?;
+        const id_alloc = Class.msgSend(objc.Object, objc.sel("alloc"), .{});
+        const id_init = id_alloc.msgSend(objc.Object, objc.sel("init"), .{});
+        break :init id_init;
+    };
+    defer desc.release();
+
+    // Set our properties
+    desc.setProperty("width", @as(c_ulong, @intCast(opts.width)));
+    desc.setProperty("height", @as(c_ulong, @intCast(opts.height)));
+    desc.setProperty("pixelFormat", @intFromEnum(opts.pixel_format));
+    desc.setProperty("usage", mtl.MTLTextureUsage{ .render_target = true });
+    desc.setProperty(
+        "resourceOptions",
+        mtl.MTLResourceOptions{
+            // Indicate that the CPU writes to this resource but never reads it.
+            .cpu_cache_mode = .write_combined,
+            .storage_mode = opts.storage_mode,
+        },
+    );
+
+    const id = opts.device.msgSend(
+        ?*anyopaque,
+        objc.sel("newTextureWithDescriptor:iosurface:plane:"),
+        .{
+            desc,
+            surface,
+            @as(c_ulong, 0),
+        },
+    ) orelse return error.MetalFailed;
+
+    const texture = objc.Object.fromId(id);
+
+    return .{
+        .surface = surface,
+        .texture = texture,
+        .width = opts.width,
+        .height = opts.height,
+    };
+}
+
+pub fn deinit(self: *Self) void {
+    self.surface.deinit();
+    self.texture.release();
+}