New gradient global settings

settings/Settings.go

@@ -46,6 +46,8 @@ type Settings struct {
 	// GradientBlur Amount of blur to apply to gradients
 	GradientBlur float64
 
+	GradientApplyOverlapOnTransparency bool
+
 	// BitmapPaletteSize Number of colors bitmap shapes will be paletted into.
 	// Transparency is not included and will be handled separately. Set to 0 to disable.
 	BitmapPaletteSize int
@@ -55,6 +57,9 @@ type Settings struct {
 }
 
 const GradientAutoSlices = -1
+
+// DefaultASSDrawingScale libass uses a fixed precision decimal of size 26.6
+// Using scale 6 allows getting accurate precision without using decimals, as it will be later divided by the drawing scale.
 const DefaultASSDrawingScale = 6
 const DefaultASSDrawingPrecision = 2
 
@@ -71,9 +76,11 @@ var GlobalSettings = Settings{
 
 	KeyFrameInterval: 0,
 
-	GradientSlices:  GradientAutoSlices,
-	GradientOverlap: 2,
-	GradientBlur:    0.1,
+	GradientSlices: GradientAutoSlices,
+	//TODO: this has issues with transparent backgrounds
+	GradientOverlap:                    2,
+	GradientBlur:                       0.1,
+	GradientApplyOverlapOnTransparency: false,
 
 	BitmapPaletteSize:  32,
 	BitmapMaxDimension: 256,

types/shapes/Gradient.go

@@ -80,11 +80,11 @@ var GradientBounds = Rectangle[float64]{
 
 const GradientRatioDivisor = math.MaxUint8
 
-func InterpolateGradient(gradient Gradient, gradientSlices int) (result []GradientSlice) {
-	items := gradient.GetItems()
+func (g Gradient) Interpolate(gradientSlices int) (result []GradientSlice) {
+	items := g.GetItems()
 	//TODO: spread modes
 
-	interpolationMode := gradient.InterpolationMode
+	interpolationMode := g.InterpolationMode
 
 	first := items[0]
 	last := items[len(items)-1]
@@ -115,8 +115,8 @@ func InterpolateGradient(gradient Gradient, gradientSlices int) (result []Gradie
 
 		maxColorDistance := max(math.Abs(float64(prevColor.R)-float64(currentColor.R)), math.Abs(float64(prevColor.G)-float64(currentColor.G)), math.Abs(float64(prevColor.B)-float64(currentColor.B)), math.Abs(float64(prevColor.Alpha)-float64(currentColor.Alpha)))
 
-		prevPosition := float64(prevItem.Ratio)
-		currentPosition := float64(item.Ratio)
+		prevPosition := float64(prevItem.Ratio) / GradientRatioDivisor
+		currentPosition := float64(item.Ratio) / GradientRatioDivisor
 		distance := math.Abs(currentPosition - prevPosition)
 
 		var partitions int
@@ -126,7 +126,7 @@ func InterpolateGradient(gradient Gradient, gradientSlices int) (result []Gradie
 			//TODO: better heuristic for change including distance in ratio
 			partitions = max(1, int(math.Ceil(min(GradientRatioDivisor/float64(len(items)+1), max(1, math.Ceil(maxColorDistance))))))
 		} else {
-			partitions = max(1, int(math.Ceil((distance/GradientRatioDivisor)*float64(gradientSlices))))
+			partitions = max(1, int(math.Ceil(distance*float64(gradientSlices))))
 		}
 
 		fromPos := prevPosition
@@ -141,8 +141,8 @@ func InterpolateGradient(gradient Gradient, gradientSlices int) (result []Gradie
 			toPos := math2.Lerp(prevPosition, currentPosition, ratio)
 
 			result = append(result, GradientSlice{
-				Start: fromPos / GradientRatioDivisor,
-				End:   toPos / GradientRatioDivisor,
+				Start: fromPos,
+				End:   toPos,
 				Color: color,
 			})
 			fromPos = toPos

types/shapes/LinearGradient.go

@@ -3,6 +3,7 @@ package shapes
 import (
 	swfsubtypes "git.gammaspectra.live/WeebDataHoarder/swf-go/subtypes"
 	"git.gammaspectra.live/WeebDataHoarder/swf-go/types"
+	"git.gammaspectra.live/WeebDataHoarder/swf2ass-go/settings"
 	"git.gammaspectra.live/WeebDataHoarder/swf2ass-go/types/math"
 )
 
@@ -27,13 +28,16 @@ func interpolateLinearGradient(self Gradient, overlap, blur float64, gradientSli
 
 	vOverlap := math.NewVector2(overlap, 0).Divide(2)
 
-	items := InterpolateGradient(self, gradientSlices)
-	for _, i := range items {
-		if i.Color.Alpha != 255 {
-			//transparency! remove overlaps
-			blur = 0
-			overlap = 0
-			break
+	items := self.Interpolate(gradientSlices)
+
+	if !settings.GlobalSettings.GradientApplyOverlapOnTransparency {
+		for _, i := range items {
+			if i.Color.Alpha != 255 {
+				//transparency! remove overlaps
+				blur = 0
+				overlap = 0
+				break
+			}
 		}
 	}
 

types/shapes/RadialGradient.go

@@ -3,6 +3,7 @@ package shapes
 import (
 	swfsubtypes "git.gammaspectra.live/WeebDataHoarder/swf-go/subtypes"
 	"git.gammaspectra.live/WeebDataHoarder/swf-go/types"
+	"git.gammaspectra.live/WeebDataHoarder/swf2ass-go/settings"
 	"git.gammaspectra.live/WeebDataHoarder/swf2ass-go/types/math"
 	math2 "math"
 )
@@ -13,13 +14,16 @@ func interpolateRadialGradient(self Gradient, overlap, blur float64, gradientSli
 
 	//TODO spreadMode
 
-	items := InterpolateGradient(self, gradientSlices)
-	for _, i := range items {
-		if i.Color.Alpha != 255 {
-			//transparency! remove overlaps
-			blur = 0
-			overlap = 0
-			break
+	items := self.Interpolate(gradientSlices)
+
+	if !settings.GlobalSettings.GradientApplyOverlapOnTransparency {
+		for _, i := range items {
+			if i.Color.Alpha != 255 {
+				//transparency! remove overlaps
+				blur = 0
+				overlap = 0
+				break
+			}
 		}
 	}