adding base depth buffers

src/soft/device/Renderer.zig

@@ -59,12 +59,25 @@ pub const DrawCall = struct {
     viewport: vk.Viewport,
     scissor: vk.Rect2D,
 
+    color_attachments: []*base.ImageView,
+    depth_attachment: ?*base.ImageView,
+
+    render_pass: *SoftRenderPass,
+    framebuffer: *SoftFramebuffer,
+
     fn init(allocator: std.mem.Allocator, vertex_count: usize, instance_count: usize, renderer: *Self) VkError!@This() {
+        const framebuffer = renderer.framebuffer orelse return VkError.InvalidHandleDrv;
+        const render_pass = renderer.render_pass orelse return VkError.InvalidHandleDrv;
+
         const self: @This() = .{
             .vertices = allocator.alloc(Vertex, vertex_count * instance_count) catch return VkError.OutOfDeviceMemory,
             .renderer = renderer,
             .viewport = undefined,
             .scissor = undefined,
+            .color_attachments = framebuffer.interface.attachments[0..],
+            .depth_attachment = if (render_pass.interface.subpasses[0].depth_stencil_attachments) |desc| framebuffer.interface.attachments[desc.attachment] else null,
+            .render_pass = render_pass,
+            .framebuffer = framebuffer,
         };
 
         for (self.vertices) |*vertex| {

src/soft/device/blitter.zig

@@ -577,7 +577,9 @@ pub fn readFloat4(map: []const u8, src_format: vk.Format) F32x4 {
         .r32_uint,
         => c[0] = @floatFromInt(std.mem.bytesToValue(u32, map)),
 
-        .r32_sfloat => c[0] = std.mem.bytesToValue(f32, map),
+        .d32_sfloat,
+        .r32_sfloat,
+        => c[0] = std.mem.bytesToValue(f32, map),
 
         .r32g32b32a32_sfloat => c = std.mem.bytesToValue(F32x4, map),
 

src/soft/device/rasterizer/bresenham.zig

@@ -119,7 +119,8 @@ fn runWrapper(data: RunData) void {
 }
 
 inline fn run(data: RunData) !void {
-    const render_target_view: *base.ImageView = (data.draw_call.renderer.framebuffer orelse return).interface.attachments[0];
+    const color_attachment = if (data.draw_call.render_pass.interface.subpasses[0].color_attachments) |attachments| attachments[0].attachment else return VkError.InvalidAttachmentDrv;
+    const render_target_view: *base.ImageView = data.draw_call.color_attachments[color_attachment];
     const render_target: *SoftImage = @alignCast(@fieldParentPtr("interface", render_target_view.image));
 
     var step = data.start_step;

src/soft/device/rasterizer/edge_function.zig

@@ -108,9 +108,13 @@ fn runWrapper(data: RunData) void {
 }
 
 inline fn run(data: RunData) !void {
-    const render_target_view: *base.ImageView = (data.draw_call.renderer.framebuffer orelse return).interface.attachments[0];
+    const color_attachment = if (data.draw_call.render_pass.interface.subpasses[0].color_attachments) |attachments| attachments[0].attachment else return VkError.InvalidAttachmentDrv;
+    const render_target_view: *base.ImageView = data.draw_call.color_attachments[color_attachment];
     const render_target: *SoftImage = @alignCast(@fieldParentPtr("interface", render_target_view.image));
 
+    const depth_attachment_view: ?*base.ImageView = if (data.draw_call.depth_attachment) |view| view else null;
+    const depth_attachment: ?*SoftImage = if (depth_attachment_view) |view| @alignCast(@fieldParentPtr("interface", view.image)) else null;
+
     var y = data.min_y;
     while (y <= data.max_y) : (y += 1) {
         var x = data.min_x;
@@ -138,6 +142,40 @@ inline fn run(data: RunData) !void {
             const b2 = w2 / data.area;
             const z = (b0 * data.v0.position[2]) + (b1 * data.v1.position[2]) + (b2 * data.v2.position[2]);
 
+            if (depth_attachment) |depth| {
+                const depth_value = try depth.readFloat4(
+                    .{
+                        .x = x,
+                        .y = y,
+                        .z = 0,
+                    },
+                    .{
+                        .aspect_mask = depth_attachment_view.?.subresource_range.aspect_mask,
+                        .mip_level = depth_attachment_view.?.subresource_range.base_mip_level,
+                        .array_layer = depth_attachment_view.?.subresource_range.base_array_layer,
+                    },
+                    depth_attachment_view.?.format,
+                );
+
+                if (z >= depth_value[0])
+                    continue;
+
+                try depth.writeFloat4(
+                    .{
+                        .x = x,
+                        .y = y,
+                        .z = 0,
+                    },
+                    .{
+                        .aspect_mask = depth_attachment_view.?.subresource_range.aspect_mask,
+                        .mip_level = depth_attachment_view.?.subresource_range.base_mip_level,
+                        .array_layer = depth_attachment_view.?.subresource_range.base_array_layer,
+                    },
+                    depth_attachment_view.?.format,
+                    zm.f32x4s(z),
+                );
+            }
+
             const pixel = fragment.shaderInvocation(
                 data.allocator,
                 data.draw_call,
@@ -156,7 +194,7 @@ inline fn run(data: RunData) !void {
                 .{
                     .x = x,
                     .y = y,
-                    .z = 0, // FIXME
+                    .z = 0,
                 },
                 .{
                     .aspect_mask = render_target_view.subresource_range.aspect_mask,