1 files changed, 89 insertions, 0 deletions
diff --git a/src/screen/drm/crtc.zig b/src/screen/drm/crtc.zig
new file mode 100644
index 0000000..6130c86
--- /dev/null
+++ b/src/screen/drm/crtc.zig
@@ -0,0 +1,89 @@
+const std = @import("std");
+const drm = @import("root.zig");
+
+pub const Crtc = struct {
+	const Self = @This();
+
+	connector_ids: ?*u32,
+	count_connectors: u32,
+	id: u32,
+	buffer_id: u32,
+	x: u32,
+	y: u32,
+	mode: drm.Connector.Mode,
+	mode_valid: u32,
+	gamma_size: u32,
+	card: *drm.Card,
+
+	pub fn init(card: *drm.Card, id: u32) !Self {
+		var raw = std.mem.zeroInit(drm.request.Crtc, .{ .id = id });
+		try card.request(.get_crtc, &raw);
+		return .{
+			.connector_ids = raw.connector_ids,
+			.count_connectors = raw.count_connectors,
+			.id = raw.id,
+			.buffer_id = raw.buffer_id,
+			.x = raw.x,
+			.y = raw.y,
+			.mode = raw.mode,
+			.mode_valid = raw.mode_valid,
+			.gamma_size = raw.gamma_size,
+			.card = card,
+	};
+	}
+
+	pub fn attach(
+		self: *Self,
+		buffer: *drm.Buffer,
+		connector: *drm.Connector,
+		mode: drm.Connector.Mode
+	) !void {
+		self.connector_ids = &connector.id;
+		self.count_connectors = 1;
+
+		var crtc = drm.request.Crtc {
+			.id = self.id,
+			.x = self.x,
+			.y = self.y,
+			.buffer_id = buffer.crtc.id,
+			.connector_ids = self.connector_ids,
+			.count_connectors = self.count_connectors,
+			.mode = mode,
+			.mode_valid = 1,
+			.gamma_size = self.gamma_size,
+	};
+
+		try self.card.request(.set_crtc, &crtc);
+	}
+
+	pub fn page_flip(self: *Self, buffer: *drm.Buffer) !void {
+		buffer.swap();
+
+		var flip = std.mem.zeroInit(drm.request.PageFlip, .{
+			.buffer_id = buffer.crtc.id,
+			.crtc_id = self.id,
+			.flags = std.mem.zeroInit(drm.request.PageFlip.Event, .{ .event = true }),
+		});
+
+		try self.card.request(.page_flip, &flip);
+	}
+
+	pub fn detach(self: *Self) void {
+		var crtc = drm.request.Crtc {
+			.id = self.id,
+			.x = self.x,
+			.y = self.y,
+			.buffer_id = self.buffer_id,
+			.connector_ids = self.connector_ids,
+			.count_connectors = self.count_connectors,
+			.mode = self.mode,
+			.mode_valid = self.mode_valid,
+			.gamma_size = self.gamma_size,
+	};
+
+		self.card.request(
+			.set_crtc,
+			&crtc
+		) catch |err| std.debug.panic("set crtc failed on detach: {}", .{err});
+	}
+};