graphicscommand: Dump internal image info on the debug mode

Closes #1714

internal/debug/debug_ebitendebug.go

@@ -21,6 +21,8 @@ import (
 	"fmt"
 )
 
+const IsDebug = true
+
 func Logf(format string, args ...interface{}) {
 	fmt.Printf(format, args...)
 }

internal/debug/debug_notebitendebug.go

@@ -17,5 +17,7 @@
 
 package debug
 
+const IsDebug = false
+
 func Logf(format string, args ...interface{}) {
 }

internal/graphicscommand/command.go

@@ -217,7 +217,7 @@ func (q *commandQueue) flush() error {
 
 	es := q.indices
 	vs := q.vertices
-	debug.Logf("--\nGraphics commands:\n")
+	debug.Logf("Graphics commands:\n")
 
 	if theGraphicsDriver.HasHighPrecisionFloat() {
 		n := q.nvertices / graphics.VertexFloatNum

internal/graphicscommand/image.go

@@ -18,9 +18,11 @@ import (
 	"fmt"
 	"image"
 	"os"
+	"sort"
 	"strings"
 
 	"github.com/hajimehoshi/ebiten/v2/internal/affine"
+	"github.com/hajimehoshi/ebiten/v2/internal/debug"
 	"github.com/hajimehoshi/ebiten/v2/internal/driver"
 	"github.com/hajimehoshi/ebiten/v2/internal/graphics"
 	"github.com/hajimehoshi/ebiten/v2/internal/png"
@@ -240,3 +242,13 @@ func (i *Image) Dump(path string, blackbg bool, rect image.Rectangle) error {
 	}
 	return nil
 }
+
+func LogImagesInfo(images []*Image) {
+	sort.Slice(images, func(a, b int) bool {
+		return images[a].id < images[b].id
+	})
+	for _, i := range images {
+		w, h := i.InternalSize()
+		debug.Logf("  %d: (%d, %d)\n", i.id, w, h)
+	}
+}

internal/restorable/images.go

@@ -18,6 +18,7 @@ import (
 	"image"
 	"path/filepath"
 
+	"github.com/hajimehoshi/ebiten/v2/internal/debug"
 	"github.com/hajimehoshi/ebiten/v2/internal/driver"
 	"github.com/hajimehoshi/ebiten/v2/internal/graphicscommand"
 )
@@ -57,6 +58,15 @@ var theImages = &images{
 //
 // ResolveStaleImages is intended to be called at the end of a frame.
 func ResolveStaleImages() error {
+	if debug.IsDebug {
+		debug.Logf("Internal image sizes:\n")
+		imgs := make([]*graphicscommand.Image, 0, len(theImages.images))
+		for i := range theImages.images {
+			imgs = append(imgs, i.image)
+		}
+		graphicscommand.LogImagesInfo(imgs)
+	}
+
 	if err := graphicscommand.FlushCommands(); err != nil {
 		return err
 	}

uicontext.go

@@ -160,6 +160,8 @@ func (c *uiContext) update(updateCount int) error {
 		return err
 	}
 
+	debug.Logf("----\n")
+
 	if err := buffered.BeginFrame(); err != nil {
 		return err
 	}
@@ -185,7 +187,7 @@ func (c *uiContext) updateImpl(updateCount int) error {
 		updateCount = 1
 		c.updateCalled = true
 	}
-	debug.Logf("--\nUpdate count per frame: %d\n", updateCount)
+	debug.Logf("Update count per frame: %d\n", updateCount)
 
 	for i := 0; i < updateCount; i++ {
 		if err := hooks.RunBeforeUpdateHooks(); err != nil {