video run extraction

2026-09-17 20:21:16 +03:00
parent 07769859f7
commit d341d22611
3 changed files with 213 additions and 204 deletions
@@ -0,0 +1,133 @@
+package video
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"log"
+	"mxl-pattern-generator/internal/generator"
+
+	"github.com/qvest-digital/go-mxl/mxl"
+)
+
+func Run(ctx context.Context, inst *mxl.Instance, cfg Config) (runErr error) {
+	pattern, ok := patterns[cfg.Pattern]
+	if !ok {
+		return fmt.Errorf("unknown video pattern %q", cfg.Pattern)
+	}
+
+	// TODO: fall back to a CPU generator if GPU initialization fails.
+	gen, err := generator.NewWGPUGenerator(cfg.Width(), cfg.Height(), pattern.kernelPath)
+	if err != nil {
+		return fmt.Errorf("initialize wgpu video generator: %w", err)
+	}
+	defer func() {
+		if err := gen.Close(); err != nil {
+			runErr = errors.Join(runErr, fmt.Errorf("close video generator: %w", err))
+		}
+	}()
+
+	overlay, err := buildTextOverlay(cfg)
+	if err != nil {
+		return err
+	}
+
+	flowJSON, err := json.Marshal(cfg.Definition)
+	if err != nil {
+		return fmt.Errorf("marshal video flow definition: %w", err)
+	}
+	writer, isCreated, err := inst.NewWriter(string(flowJSON))
+	if err != nil {
+		return fmt.Errorf("create video writer: %w", err)
+	}
+	defer func() {
+		if err := writer.Close(); err != nil {
+			runErr = errors.Join(runErr, fmt.Errorf("close video writer: %w", err))
+		}
+	}()
+	if !isCreated {
+		log.Printf("reusing existing video flow: %s", cfg.ID())
+	}
+
+	rate := writer.Config().Common.GrainRate
+	idx := mxl.CurrentIndex(rate)
+	log.Printf("writing video flow grainRate=%d/%d starting at idx=%d", rate.Num, rate.Den, idx)
+
+	var grainsWritten int64
+	var tick uint32 // Small animation counter; shaders cannot use the full grain index yet.
+	for {
+		select {
+		case <-ctx.Done():
+			log.Printf("stopping video after %d grains", grainsWritten)
+			return nil
+		default:
+		}
+
+		grain, err := writer.OpenGrain(idx)
+		if err != nil {
+			return fmt.Errorf("open video grain %d: %w", idx, err)
+		}
+		if err := gen.GenerateFrame(grain.Payload, int(tick)); err != nil {
+			return cancelGrain(grain, fmt.Errorf("generate frame for grain %d: %w", idx, err))
+		}
+		if overlay != nil {
+			if err := overlay.ApplyV210(grain.Payload); err != nil {
+				return cancelGrain(grain, fmt.Errorf("apply text overlay to grain %d: %w", idx, err))
+			}
+		}
+		if err := grain.Commit(grain.TotalSlices, 0); err != nil {
+			return fmt.Errorf("commit video grain %d: %w", idx, err)
+		}
+
+		grainsWritten++
+		idx++
+		tick++
+		if grainsWritten%100 == 0 {
+			log.Printf("video grains written=%d, next index=%d", grainsWritten, idx)
+		}
+		mxl.SleepNs(mxl.NsUntilIndex(idx, rate))
+	}
+}
+
+func cancelGrain(grain *mxl.GrainWriteAccess, cause error) error {
+	if err := grain.Cancel(); err != nil {
+		return errors.Join(cause, fmt.Errorf("cancel video grain: %w", err))
+	}
+	return cause
+}
+
+func buildTextOverlay(cfg Config) (overlay *generator.TextOverlay, resultErr error) {
+	if cfg.Overlay.Text == "" {
+		return nil, nil
+	}
+	if cfg.Overlay.X < 0 || cfg.Overlay.X > int(cfg.Width()) ||
+		cfg.Overlay.Y < 0 || cfg.Overlay.Y > int(cfg.Height()) {
+		return nil, fmt.Errorf("text overlay position (%d, %d) is outside the %dx%d video frame",
+			cfg.Overlay.X, cfg.Overlay.Y, cfg.Width(), cfg.Height())
+	}
+
+	face, err := generator.LoadFace("assets/fonts/JetBrainsMonoNLNerdFontMono-Regular.ttf", 48)
+	if err != nil {
+		return nil, fmt.Errorf("load text overlay font: %w", err)
+	}
+	defer func() {
+		if err := face.Close(); err != nil {
+			resultErr = errors.Join(resultErr, fmt.Errorf("close text overlay font: %w", err))
+		}
+	}()
+
+	overlay, err = generator.NewTextOverlay(
+		cfg.Overlay.Text,
+		int(cfg.Width()),
+		int(cfg.Height()),
+		cfg.Overlay.X,
+		cfg.Overlay.Y,
+		cfg.Overlay.Position,
+		face,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("create text overlay: %w", err)
+	}
+	return overlay, nil
+}