132 lines
3.7 KiB
Zig
132 lines
3.7 KiB
Zig
//! Wrapper for handling render passes.
|
|
const Self = @This();
|
|
|
|
const std = @import("std");
|
|
const Allocator = std.mem.Allocator;
|
|
const objc = @import("objc");
|
|
|
|
const mtl = @import("api.zig");
|
|
const Renderer = @import("../generic.zig").Renderer(Metal);
|
|
const Metal = @import("../Metal.zig");
|
|
const Target = @import("Target.zig");
|
|
const RenderPass = @import("RenderPass.zig");
|
|
|
|
const Health = @import("../../renderer.zig").Health;
|
|
|
|
const log = std.log.scoped(.metal);
|
|
|
|
/// Options for beginning a frame.
|
|
pub const Options = struct {
|
|
/// MTLCommandQueue
|
|
queue: objc.Object,
|
|
};
|
|
|
|
/// MTLCommandBuffer
|
|
buffer: objc.Object,
|
|
|
|
block: CompletionBlock.Context,
|
|
|
|
/// Begin encoding a frame.
|
|
pub fn begin(
|
|
opts: Options,
|
|
/// Once the frame has been completed, the `frameCompleted` method
|
|
/// on the renderer is called with the health status of the frame.
|
|
renderer: *Renderer,
|
|
/// The target is presented via the provided renderer's API when completed.
|
|
target: *Target,
|
|
) !Self {
|
|
const buffer = opts.queue.msgSend(
|
|
objc.Object,
|
|
objc.sel("commandBuffer"),
|
|
.{},
|
|
);
|
|
|
|
// Create our block to register for completion updates.
|
|
// The block is deallocated by the objC runtime on success.
|
|
const block = CompletionBlock.init(
|
|
.{
|
|
.renderer = renderer,
|
|
.target = target,
|
|
.sync = false,
|
|
},
|
|
&bufferCompleted,
|
|
);
|
|
|
|
return .{ .buffer = buffer, .block = block };
|
|
}
|
|
|
|
/// This is the block type used for the addCompletedHandler callback.
|
|
const CompletionBlock = objc.Block(struct {
|
|
renderer: *Renderer,
|
|
target: *Target,
|
|
sync: bool,
|
|
}, .{
|
|
objc.c.id, // MTLCommandBuffer
|
|
}, void);
|
|
|
|
fn bufferCompleted(
|
|
block: *const CompletionBlock.Context,
|
|
buffer_id: objc.c.id,
|
|
) callconv(.c) void {
|
|
const buffer = objc.Object.fromId(buffer_id);
|
|
|
|
// Get our command buffer status to pass back to the generic renderer.
|
|
const status = buffer.getProperty(mtl.MTLCommandBufferStatus, "status");
|
|
const health: Health = switch (status) {
|
|
.@"error" => .unhealthy,
|
|
else => .healthy,
|
|
};
|
|
|
|
// If the frame is healthy, present it.
|
|
if (health == .healthy) {
|
|
block.renderer.api.present(
|
|
block.target.*,
|
|
block.sync,
|
|
) catch |err| {
|
|
log.err("Failed to present render target: err={}", .{err});
|
|
};
|
|
}
|
|
|
|
block.renderer.frameCompleted(health);
|
|
}
|
|
|
|
/// Add a render pass to this frame with the provided attachments.
|
|
/// Returns a RenderPass which allows render steps to be added.
|
|
pub inline fn renderPass(
|
|
self: *const Self,
|
|
attachments: []const RenderPass.Options.Attachment,
|
|
) RenderPass {
|
|
return RenderPass.begin(.{
|
|
.attachments = attachments,
|
|
.command_buffer = self.buffer,
|
|
});
|
|
}
|
|
|
|
/// Complete this frame and present the target.
|
|
///
|
|
/// If `sync` is true, this will block until the frame is presented.
|
|
pub inline fn complete(self: *Self, sync: bool) void {
|
|
// If we don't need to complete synchronously,
|
|
// we add our block as a completion handler.
|
|
//
|
|
// It will be copied when we add the handler, and then the
|
|
// copy will be deallocated by the objc runtime on success.
|
|
if (!sync) {
|
|
self.buffer.msgSend(
|
|
void,
|
|
objc.sel("addCompletedHandler:"),
|
|
.{&self.block},
|
|
);
|
|
}
|
|
|
|
self.buffer.msgSend(void, objc.sel("commit"), .{});
|
|
|
|
// If we need to complete synchronously, we wait until
|
|
// the buffer is completed and invoke the block directly.
|
|
if (sync) {
|
|
self.buffer.msgSend(void, "waitUntilCompleted", .{});
|
|
self.block.sync = true;
|
|
CompletionBlock.invoke(&self.block, .{self.buffer.value});
|
|
}
|
|
}
|