refactoring finished

assets/embed.go

@@ -0,0 +1,8 @@
+package assets
+
+import _ "embed"
+
+// JetBrainsMono contains the font used for video text overlays.
+//
+//go:embed fonts/JetBrainsMonoNLNerdFontMono-Regular.ttf
+var JetBrainsMono []byte

internal/generator/text.go

@@ -33,9 +33,19 @@ func LoadFace(path string, size float64) (font.Face, error) {
 	if err != nil {
 		return nil, fmt.Errorf("text: %w", err)
 	}
+	face, err := NewFace(data, size)
+	if err != nil {
+		return nil, fmt.Errorf("text: load %s: %w", path, err)
+	}
+	return face, nil
+}
+
+// NewFace parses TTF/OTF data and builds a render-ready face at the given
+// pixel size (DPI 72, full hinting for crisp video text).
+func NewFace(data []byte, size float64) (font.Face, error) {
 	f, err := opentype.Parse(data)
 	if err != nil {
-		return nil, fmt.Errorf("text: parse %s: %w", path, err)
+		return nil, fmt.Errorf("parse font: %w", err)
 	}
 	face, err := opentype.NewFace(f, &opentype.FaceOptions{
 		Size:    size,
@@ -43,7 +53,7 @@ func LoadFace(path string, size float64) (font.Face, error) {
 		Hinting: font.HintingFull,
 	})
 	if err != nil {
-		return nil, fmt.Errorf("text: face %s: %w", path, err)
+		return nil, fmt.Errorf("create font face: %w", err)
 	}
 	return face, nil
 }

internal/generator/text_test.go

@@ -1,17 +1,17 @@
 package generator
 
 import (
-	"path/filepath"
 	"strings"
 	"testing"
 
+	"mxl-pattern-generator/assets"
+
 	"golang.org/x/image/font"
 )
 
 func testFace(t *testing.T, size float64) font.Face {
 	t.Helper()
-	face, err := LoadFace(filepath.Join("..", "..", "assets", "fonts",
-		"JetBrainsMonoNLNerdFontMono-Regular.ttf"), size)
+	face, err := NewFace(assets.JetBrainsMono, size)
 	if err != nil {
 		t.Fatalf("LoadFace: %v", err)
 	}

internal/generator/wgpu.go

@@ -6,7 +6,6 @@ import (
 	"context"
 	"encoding/binary"
 	"fmt"
-	"os"
 	"time"
 
 	"github.com/gogpu/gputypes"
@@ -47,7 +46,7 @@ var _ FrameGenerator = (*WGPUGenerator)(nil)
 // WGPUOption customizes NewWGPUGenerator.
 type WGPUOption func(*WGPUGenerator)
 
-func NewWGPUGenerator(width, height uint, kernelPath string, opts ...WGPUOption) (*WGPUGenerator, error) {
+func NewWGPUGenerator(width, height uint, wgsl string, opts ...WGPUOption) (*WGPUGenerator, error) {
 	g := &WGPUGenerator{
 		width:  int(width),
 		height: int(height),
@@ -75,13 +74,8 @@ func NewWGPUGenerator(width, height uint, kernelPath string, opts ...WGPUOption)
 	}
 	g.queue = g.device.Queue()
 
-	wgsl, err := os.ReadFile(kernelPath)
-	if err != nil {
-		g.Close()
-		return nil, fmt.Errorf("wgpu: read kernel: %w", err)
-	}
 	if g.shader, err = g.device.CreateShaderModule(&wgpu.ShaderModuleDescriptor{
-		Label: "v210-shader", WGSL: string(wgsl),
+		Label: "v210-shader", WGSL: wgsl,
 	}); err != nil {
 		g.Close()
 		return nil, fmt.Errorf("wgpu: shader: %w", err)

internal/generator/wgpu_move_test.go

@@ -1,13 +1,18 @@
 package generator
 
 import (
-	"path/filepath"
 	"testing"
+
+	"mxl-pattern-generator/kernels"
 )
 
 func TestWGPUMoveSquare(t *testing.T) {
 	const width, height = 1920, 1080
-	g, err := NewWGPUGenerator(width, height, filepath.Join("..", "..", "kernels", "dynamic", "smpteBars.wgsl"))
+	shader, err := kernels.Read("dynamic/smpteBars.wgsl")
+	if err != nil {
+		t.Fatalf("read shader: %v", err)
+	}
+	g, err := NewWGPUGenerator(width, height, string(shader))
 	if err != nil {
 		t.Fatalf("init: %v", err)
 	}

internal/generator/wgpu_test.go

@@ -1,13 +1,18 @@
 package generator
 
 import (
-	"path/filepath"
 	"testing"
+
+	"mxl-pattern-generator/kernels"
 )
 
 func TestWGPUSMPTEPattern(t *testing.T) {
 	const width, height = 1920, 1080
-	g, err := NewWGPUGenerator(width, height, filepath.Join("..", "..", "kernels", "static", "smpteBars.wgsl"))
+	shader, err := kernels.Read("static/smpteBars.wgsl")
+	if err != nil {
+		t.Fatalf("read shader: %v", err)
+	}
+	g, err := NewWGPUGenerator(width, height, string(shader))
 	if err != nil {
 		t.Fatalf("init: %v", err)
 	}

internal/video/pattern.go

@@ -1,6 +1,11 @@
 package video
 
-import "sort"
+import (
+	"fmt"
+	"sort"
+
+	"mxl-pattern-generator/kernels"
+)
 
 type PatternInfo struct {
 	Name        string
@@ -9,52 +14,60 @@ type PatternInfo struct {
 
 type pattern struct {
 	PatternInfo
-	kernelPath string
+	kernelSource string
 }
 
 var patterns = map[string]pattern{
 	"ebu75": {
-		PatternInfo: PatternInfo{Name: "ebu75", Description: "EBU 75% Color Bar Signal"},
-		kernelPath:  "kernels/static/ebu75.wgsl",
+		PatternInfo:  PatternInfo{Name: "ebu75", Description: "EBU 75% Color Bar Signal"},
+		kernelSource: mustReadKernel("static/ebu75.wgsl"),
 	},
 	"ebu75-move": {
-		PatternInfo: PatternInfo{Name: "ebu75-move", Description: "EBU 75% Color Bar Signal with moving square"},
-		kernelPath:  "kernels/dynamic/ebu75.wgsl",
+		PatternInfo:  PatternInfo{Name: "ebu75-move", Description: "EBU 75% Color Bar Signal with moving square"},
+		kernelSource: mustReadKernel("dynamic/ebu75.wgsl"),
 	},
 	"ebu100": {
-		PatternInfo: PatternInfo{Name: "ebu100", Description: "EBU 100% Color Bar Signal"},
-		kernelPath:  "kernels/static/ebu100.wgsl",
+		PatternInfo:  PatternInfo{Name: "ebu100", Description: "EBU 100% Color Bar Signal"},
+		kernelSource: mustReadKernel("static/ebu100.wgsl"),
 	},
 	"ebu100-move": {
-		PatternInfo: PatternInfo{Name: "ebu100-move", Description: "EBU 100% Color Bar Signal with moving square"},
-		kernelPath:  "kernels/dynamic/ebu100.wgsl",
+		PatternInfo:  PatternInfo{Name: "ebu100-move", Description: "EBU 100% Color Bar Signal with moving square"},
+		kernelSource: mustReadKernel("dynamic/ebu100.wgsl"),
 	},
 	"smpte": {
-		PatternInfo: PatternInfo{Name: "smpte", Description: "SMPTE RP-219 Color Bar Signal"},
-		kernelPath:  "kernels/static/smpteBars.wgsl",
+		PatternInfo:  PatternInfo{Name: "smpte", Description: "SMPTE RP-219 Color Bar Signal"},
+		kernelSource: mustReadKernel("static/smpteBars.wgsl"),
 	},
 	"smpte-move": {
-		PatternInfo: PatternInfo{Name: "smpte-move", Description: "SMPTE RP-219 Color Bar Signal with moving square"},
-		kernelPath:  "kernels/dynamic/smpteBars.wgsl",
+		PatternInfo:  PatternInfo{Name: "smpte-move", Description: "SMPTE RP-219 Color Bar Signal with moving square"},
+		kernelSource: mustReadKernel("dynamic/smpteBars.wgsl"),
 	},
 	"gray-bars": {
-		PatternInfo: PatternInfo{Name: "gray-bars", Description: "13-step grayscale bars (Y 64..940)"},
-		kernelPath:  "kernels/static/yBars.wgsl",
+		PatternInfo:  PatternInfo{Name: "gray-bars", Description: "13-step grayscale bars (Y 64..940)"},
+		kernelSource: mustReadKernel("static/yBars.wgsl"),
 	},
 	"gray-bars-move": {
-		PatternInfo: PatternInfo{Name: "gray-bars-move", Description: "13-step grayscale bars (Y 64..940) with moving square"},
-		kernelPath:  "kernels/dynamic/yBars.wgsl",
+		PatternInfo:  PatternInfo{Name: "gray-bars-move", Description: "13-step grayscale bars (Y 64..940) with moving square"},
+		kernelSource: mustReadKernel("dynamic/yBars.wgsl"),
 	},
 	"gray-ramp": {
-		PatternInfo: PatternInfo{Name: "gray-ramp", Description: "Y gradient (black -> 100% white)"},
-		kernelPath:  "kernels/static/yRamp.wgsl",
+		PatternInfo:  PatternInfo{Name: "gray-ramp", Description: "Y gradient (black -> 100% white)"},
+		kernelSource: mustReadKernel("static/yRamp.wgsl"),
 	},
 	"gray-ramp-move": {
-		PatternInfo: PatternInfo{Name: "gray-ramp-move", Description: "Y gradient with moving square"},
-		kernelPath:  "kernels/dynamic/yRamp.wgsl",
+		PatternInfo:  PatternInfo{Name: "gray-ramp-move", Description: "Y gradient with moving square"},
+		kernelSource: mustReadKernel("dynamic/yRamp.wgsl"),
 	},
 }
 
+func mustReadKernel(name string) string {
+	source, err := kernels.Read(name)
+	if err != nil {
+		panic(fmt.Sprintf("read embedded video kernel %q: %v", name, err))
+	}
+	return string(source)
+}
+
 func HasPattern(name string) bool {
 	_, ok := patterns[name]
 	return ok

internal/video/pattern_test.go

@@ -40,8 +40,8 @@ func TestPatternRegistryKeysMatchNames(t *testing.T) {
 		if pattern.Name != name {
 			t.Errorf("pattern map key %q does not match pattern name %q", name, pattern.Name)
 		}
-		if pattern.kernelPath == "" {
-			t.Errorf("pattern %q has an empty kernel path", name)
+		if pattern.kernelSource == "" {
+			t.Errorf("pattern %q has empty kernel source", name)
 		}
 	}
 }

internal/video/runner.go

@@ -6,6 +6,8 @@ import (
 	"errors"
 	"fmt"
 	"log"
+
+	"mxl-pattern-generator/assets"
 	"mxl-pattern-generator/internal/generator"
 
 	"github.com/qvest-digital/go-mxl/mxl"
@@ -18,7 +20,7 @@ func Run(ctx context.Context, inst *mxl.Instance, cfg Config) (runErr error) {
 	}
 
 	// TODO: fall back to a CPU generator if GPU initialization fails.
-	gen, err := generator.NewWGPUGenerator(cfg.Width(), cfg.Height(), pattern.kernelPath)
+	gen, err := generator.NewWGPUGenerator(cfg.Width(), cfg.Height(), pattern.kernelSource)
 	if err != nil {
 		return fmt.Errorf("initialize wgpu video generator: %w", err)
 	}
@@ -102,7 +104,7 @@ func buildTextOverlay(cfg Config) (overlay *generator.TextOverlay, resultErr err
 		return nil, nil
 	}
 
-	face, err := generator.LoadFace("assets/fonts/JetBrainsMonoNLNerdFontMono-Regular.ttf", 48)
+	face, err := generator.NewFace(assets.JetBrainsMono, 48)
 	if err != nil {
 		return nil, fmt.Errorf("load text overlay font: %w", err)
 	}

internal/video/runner_test.go

@@ -34,9 +34,6 @@ func TestBuildTextOverlayDisabled(t *testing.T) {
 }
 
 func TestBuildTextOverlayPositioning(t *testing.T) {
-	// Production assets are resolved from the repository root.
-	t.Chdir("../..")
-
 	tests := []struct {
 		name    string
 		overlay OverlayConfig
@@ -59,8 +56,6 @@ func TestBuildTextOverlayPositioning(t *testing.T) {
 }
 
 func TestBuildTextOverlayRejectsInvalidPosition(t *testing.T) {
-	t.Chdir("../..")
-
 	tests := []struct {
 		name       string
 		overlay    OverlayConfig

kernels/embed.go

@@ -0,0 +1,12 @@
+package kernels
+
+import "embed"
+
+// files contains every built-in video pattern shader.
+//
+//go:embed static/*.wgsl dynamic/*.wgsl
+var files embed.FS
+
+func Read(name string) ([]byte, error) {
+	return files.ReadFile(name)
+}