Merge SPIRV backend with shader module

src/coral/shaders.zig

@@ -8,8 +8,6 @@ pub const Type = @import("./shaders/Type.zig");
 
 const coral = @import("./coral.zig");
 
-const spirv = @import("./shaders/spirv.zig");
-
 const std = @import("std");
 
 const tokens = @import("./shaders/tokens.zig");
@@ -349,14 +347,3 @@ pub const Uniform = struct {
     binding: u8,
     has_field: ?*const Field = null,
 };
-
-pub fn compileFragmentSpirv(arena: *std.heap.ArenaAllocator, function: *const coral.shaders.Function) spirv.BuildError!spirv.Module {
-    var module = spirv.Module{
-        .capabilities = &.{.shader},
-        .memory_model = .{ .logical, .glsl450 },
-    };
-
-    _ = try module.shaderEntryPoint(arena, .fragment, function);
-
-    return module;
-}

src/coral/shaders/Root.zig

@@ -1,5 +1,7 @@
 const coral = @import("../coral.zig");
 
+const spirv = @import("./spirv.zig");
+
 const std = @import("std");
 
 const tokens = @import("./tokens.zig");
@@ -11,6 +13,10 @@ uniforms: std.BoundedArray(*const coral.shaders.Uniform, 15) = .{},
 textures: std.BoundedArray(*const coral.shaders.Texture, 15) = .{},
 functions: std.BoundedArray(*const coral.shaders.Function, max_functions) = .{},
 
+pub const BuildError = spirv.BuildError || error{
+    InvalidEntryPoint,
+};
+
 pub const ParseResult = union(enum) {
     ok,
     failure: [:0]const u8,
@@ -18,6 +24,19 @@ pub const ParseResult = union(enum) {
 
 const Self = @This();
 
+pub fn buildSpirvFragment(self: *Self, arena: *std.heap.ArenaAllocator, identifier: []const u8) BuildError!spirv.Module {
+    var module = spirv.Module{
+        .capabilities = &.{.shader},
+        .memory_model = .{ .logical, .glsl450 },
+    };
+
+    _ = try module.shaderEntryPoint(arena, .fragment, self.hasFunction(identifier) orelse {
+        return error.InvalidEntryPoint;
+    });
+
+    return module;
+}
+
 pub fn clear(self: *Self) void {
     self.scope.clear();
     self.inputs.clear();

src/coral/shaders/spirv.zig

@@ -112,6 +112,11 @@ pub const Module = struct {
                     };
                 },
 
+                .convert => |_| {
+                    // TODO: Review how type conversions are represented in AST.
+                    unreachable;
+                },
+
                 .invoke => |invoke| {
                     const arguments = try arena.allocator().alloc(*const Value, invoke.argument_count);
 

src/ona/gfx.zig

@@ -72,12 +72,7 @@ fn compile_shaders(_: ona.Write(Context), assets: ona.Assets) !void {
 
     switch (try root.parse(&arena, try assets.load(shader_path, arena.allocator()))) {
         .ok => {
-            const spirv_module = try coral.shaders.compileFragmentSpirv(&arena, root.hasFunction("frag") orelse {
-                std.log.err("effect shader {s} requires an entry-point named `frag`", .{shader_path});
-
-                return error.ShaderParseFailure;
-            });
-
+            const spirv_module = try root.buildSpirvFragment(&arena, "frag");
             var codes = coral.Stack(u8).empty;
 
             defer {