shader: Add Metal tests

Fixes #1340

internal/shader/shader_test.go

@@ -29,13 +29,41 @@ import (
 	"github.com/hajimehoshi/ebiten/internal/shaderir/metal"
 )
 
-func normalize(str string) string {
+func glslNormalize(str string) string {
 	if strings.HasPrefix(str, glsl.FragmentPrelude) {
 		str = str[len(glsl.FragmentPrelude):]
 	}
 	return strings.TrimSpace(str)
 }
 
+func metalNormalize(str string) string {
+	if strings.HasPrefix(str, metal.Prelude) {
+		str = str[len(metal.Prelude):]
+	}
+	return strings.TrimSpace(str)
+}
+
+func compare(t *testing.T, title, got, want string) {
+	var msg string
+	gotlines := strings.Split(got, "\n")
+	wantlines := strings.Split(want, "\n")
+	for i := range gotlines {
+		if len(wantlines) <= i {
+			msg = fmt.Sprintf(`lines %d:
+got:  %s
+want: (out of range)`, i+1, gotlines[i])
+			break
+		}
+		if gotlines[i] != wantlines[i] {
+			msg = fmt.Sprintf(`lines %d:
+got:  %s
+want: %s`, i+1, gotlines[i], wantlines[i])
+			break
+		}
+	}
+	t.Errorf("%s: got: %v, want: %v\n\n%s", title, got, want, msg)
+}
+
 func TestCompile(t *testing.T) {
 	if runtime.GOOS == "js" {
 		t.Skip("file open might not be implemented in this environment")
@@ -51,6 +79,7 @@ func TestCompile(t *testing.T) {
 		Src   []byte
 		VS    []byte
 		FS    []byte
+		Metal []byte
 	}
 
 	fnames := map[string]struct{}{}
@@ -100,6 +129,15 @@ func TestCompile(t *testing.T) {
 			t.Fatalf("no expected file for %s", name)
 		}
 
+		metaln := name + ".expected.metal"
+		if _, ok := fnames[metaln]; ok {
+			metal, err := ioutil.ReadFile(filepath.Join("testdata", metaln))
+			if err != nil {
+				t.Fatal(err)
+			}
+			tc.Metal = metal
+		}
+
 		tests = append(tests, tc)
 	}
 
@@ -116,30 +154,22 @@ func TestCompile(t *testing.T) {
 				t.Error(err)
 				return
 			}
+
+			// GLSL
 			vs, fs := glsl.Compile(s)
-			if got, want := normalize(vs), normalize(string(tc.VS)); got != want {
+			if got, want := glslNormalize(vs), glslNormalize(string(tc.VS)); got != want {
-				var msg string
+				compare(t, "GLSL Vertex", got, want)
-				gotlines := strings.Split(got, "\n")
-				wantlines := strings.Split(want, "\n")
-				for i := range gotlines {
-					if len(wantlines) <= i {
-						msg = fmt.Sprintf(`lines %d:
-got:  %s
-want: (out of range)`, i+1, gotlines[i])
-						break
-					}
-					if gotlines[i] != wantlines[i] {
-						msg = fmt.Sprintf(`lines %d:
-got:  %s
-want: %s`, i+1, gotlines[i], wantlines[i])
-						break
-					}
-				}
-				t.Errorf("got: %v, want: %v\n\n%s", got, want, msg)
 			}
 			if tc.FS != nil {
-				if got, want := normalize(fs), normalize(string(tc.FS)); got != want {
+				if got, want := glslNormalize(fs), glslNormalize(string(tc.FS)); got != want {
-					t.Errorf("got: %v, want: %v", got, want)
+					compare(t, "GLSL Fragment", got, want)
+				}
+			}
+
+			if tc.Metal != nil {
+				m := metal.Compile(s, "Vertex", "Fragment")
+				if got, want := metalNormalize(m), metalNormalize(string(tc.Metal)); got != want {
+					compare(t, "Metal", got, want)
 				}
 			}
 

internal/shader/testdata/array2.expected.metal

@@ -0,0 +1,12 @@
+void F0(thread array<float2, 3>& l0);
+
+void F0(thread array<float2, 3>& l0) {
+	array<float2, 2> l1 = {};
+	array<float2, 3> l2 = {};
+	{
+		array<float2, 2> l2 = {};
+		l2 = l1;
+	}
+	l0 = l2;
+	return;
+}

internal/shader/testdata/vertex.expected.metal

@@ -0,0 +1,24 @@
+struct Attributes {
+	packed_float2 M0;
+	packed_float2 M1;
+	packed_float4 M2;
+};
+
+struct Varyings {
+	float4 Position [[position]];
+	float2 M0;
+	float4 M1;
+};
+
+vertex Varyings Vertex(
+	uint vid [[vertex_id]],
+	const device Attributes* attributes [[buffer(0)]],
+	constant float2& U0 [[buffer(1)]]) {
+	Varyings varyings = {};
+	float4x4 l0 = float4x4(0);
+	l0 = float4x4((2.0) / ((U0).x), 0.0, 0.0, 0.0, 0.0, (2.0) / ((U0).y), 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, -1.0, -1.0, 0.0, 1.0);
+	varyings.Position = (l0) * (float4(attributes[vid].M0, 0.0, 1.0));
+	varyings.M0 = attributes[vid].M1;
+	varyings.M1 = attributes[vid].M2;
+	return varyings;
+}

internal/shader/testdata/vertex_fragment.expected.metal

@@ -0,0 +1,32 @@
+struct Attributes {
+	packed_float2 M0;
+	packed_float2 M1;
+	packed_float4 M2;
+};
+
+struct Varyings {
+	float4 Position [[position]];
+	float2 M0;
+	float4 M1;
+};
+
+vertex Varyings Vertex(
+	uint vid [[vertex_id]],
+	const device Attributes* attributes [[buffer(0)]],
+	constant float2& U0 [[buffer(1)]]) {
+	Varyings varyings = {};
+	float4x4 l0 = float4x4(0);
+	l0 = float4x4((2.0) / ((U0).x), 0.0, 0.0, 0.0, 0.0, (2.0) / ((U0).y), 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, -1.0, -1.0, 0.0, 1.0);
+	varyings.Position = (l0) * (float4(attributes[vid].M0, 0.0, 1.0));
+	varyings.M0 = attributes[vid].M1;
+	varyings.M1 = attributes[vid].M2;
+	return varyings;
+}
+
+fragment float4 Fragment(
+	Varyings varyings [[stage_in]],
+	constant float2& U0 [[buffer(1)]]) {
+	float4 out = float4(0);
+	out = float4((varyings.Position).x, (varyings.M0).y, (varyings.M1).z, 1.0);
+	return out;
+}

internal/shaderir/metal/metal.go

@@ -48,20 +48,20 @@ func (c *compileContext) structName(p *shaderir.Program, t *shaderir.Type) strin
 	return n
 }
 
+const Prelude = `#include <metal_stdlib>
+
+using namespace metal;
+
+constexpr sampler texture_sampler{filter::nearest};`
+
 func Compile(p *shaderir.Program, vertex, fragment string) (shader string) {
 	c := &compileContext{
 		structNames: map[string]string{},
 	}
 
 	var lines []string
-	lines = append(lines,
+	lines = append(lines, strings.Split(Prelude, "\n")...)
-		"#include <metal_stdlib>",
+	lines = append(lines, "", "{{.Structs}}")
-		"",
-		"using namespace metal;",
-		"",
-		"{{.Structs}}",
-		"",
-		"constexpr sampler texture_sampler{filter::nearest};")
 
 	if len(p.Attributes) > 0 {
 		lines = append(lines, "")