all: rename arguments in Fragment

Updates #2767

examples/flappy/crt.go

@@ -31,11 +31,11 @@ func Warp(pos vec2) vec2 {
 	return pos/2 + 0.5
 }
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
 	// Adjust the texture position to [0, 1].
 	origin := imageSrc0Origin()
 	size := imageSrc0Size()
-	pos := texCoord
+	pos := srcPos
 	pos -= origin
 	pos /= size
 

examples/shader/chromaticaberration.go

@@ -21,12 +21,12 @@ package main
 var Time float
 var Cursor vec2
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
 	center := imageDstSize() / 2
 	amount := (center - Cursor) / 10
 	var clr vec3
-	clr.r = imageSrc2At(texCoord + amount).r
-	clr.g = imageSrc2UnsafeAt(texCoord).g
-	clr.b = imageSrc2At(texCoord - amount).b
+	clr.r = imageSrc2At(srcPos + amount).r
+	clr.g = imageSrc2UnsafeAt(srcPos).g
+	clr.b = imageSrc2At(srcPos - amount).b
 	return vec4(clr, 1)
 }

examples/shader/default.go

@@ -21,8 +21,8 @@ package main
 var Time float
 var Cursor vec2
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
-	pos := (position.xy - imageDstOrigin()) / imageDstSize()
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
+	pos := (dstPos.xy - imageDstOrigin()) / imageDstSize()
 	pos += Cursor / imageDstSize() / 4
 	clr := 0.0
 	clr += sin(pos.x*cos(Time/15)*80) + cos(pos.y*cos(Time/15)*10)

examples/shader/dissolve.go

@@ -21,16 +21,16 @@ package main
 var Time float
 var Cursor vec2
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
 	// Triangle wave to go 0-->1-->0...
 	limit := abs(2*fract(Time/3) - 1)
-	level := imageSrc3UnsafeAt(texCoord).x
+	level := imageSrc3UnsafeAt(srcPos).x
 
 	// Add a white border
 	if limit-0.1 < level && level < limit {
-		alpha := imageSrc0UnsafeAt(texCoord).w
+		alpha := imageSrc0UnsafeAt(srcPos).w
 		return vec4(alpha)
 	}
 
-	return step(limit, level) * imageSrc0UnsafeAt(texCoord)
+	return step(limit, level) * imageSrc0UnsafeAt(srcPos)
 }

examples/shader/lighting.go

@@ -21,13 +21,13 @@ package main
 var Time float
 var Cursor vec2
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
-	pos := position.xy - imageDstOrigin()
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
+	pos := dstPos.xy - imageDstOrigin()
 
 	lightpos := vec3(Cursor, 50)
 	lightdir := normalize(lightpos - vec3(pos, 0))
-	normal := normalize(imageSrc1UnsafeAt(texCoord) - 0.5)
+	normal := normalize(imageSrc1UnsafeAt(srcPos) - 0.5)
 	const ambient = 0.25
 	diffuse := 0.75 * max(0.0, dot(normal.xyz, lightdir))
-	return imageSrc0UnsafeAt(texCoord) * (ambient + diffuse)
+	return imageSrc0UnsafeAt(srcPos) * (ambient + diffuse)
 }

examples/shader/radialblur.go

@@ -21,18 +21,18 @@ package main
 var Time float
 var Cursor vec2
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
-	pos := position.xy - imageDstOrigin()
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
+	pos := dstPos.xy - imageDstOrigin()
 
 	dir := normalize(pos - Cursor)
-	clr := imageSrc2UnsafeAt(texCoord)
+	clr := imageSrc2UnsafeAt(srcPos)
 
 	samples := [...]float{
 		-22, -14, -8, -4, -2, 2, 4, 8, 14, 22,
 	}
 	sum := clr
 	for i := 0; i < len(samples); i++ {
-		sum += imageSrc2At(texCoord + dir*samples[i])
+		sum += imageSrc2At(srcPos + dir*samples[i])
 	}
 	sum /= 10 + 1
 

examples/shader/texel.go

@@ -18,8 +18,8 @@
 
 package main
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
-	pos := position.xy
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
+	pos := dstPos.xy
 	pos -= imageDstOrigin()
 	pos /= imageDstSize()
 	return vec4(pos.x, pos.y, 0, 1)

examples/shader/water.go

@@ -21,20 +21,20 @@ package main
 var Time float
 var Cursor vec2
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
-	pos := position.xy - imageDstOrigin()
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
+	pos := dstPos.xy - imageDstOrigin()
 
 	border := imageDstSize().y*0.6 + 4*cos(Time*3+pos.y/10)
 	if pos.y < border {
-		return imageSrc2UnsafeAt(texCoord)
+		return imageSrc2UnsafeAt(srcPos)
 	}
 
 	xoffset := 4 * cos(Time*3+pos.y/10)
 	yoffset := 20 * (1 + cos(Time*3+pos.y/40))
 	srcOrigin := imageSrc0Origin()
 	clr := imageSrc2At(vec2(
-		texCoord.x+xoffset,
-		-(texCoord.y+yoffset-srcOrigin.y)+border*2+srcOrigin.y,
+		srcPos.x+xoffset,
+		-(srcPos.y+yoffset-srcOrigin.y)+border*2+srcOrigin.y,
 	)).rgb
 
 	overlay := vec3(0.5, 1, 1)

gameforui.go

@@ -28,10 +28,10 @@ const screenShaderSrc = `//kage:unit pixels
 
 package main
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
 	// Blend source colors in a square region, which size is 1/scale.
 	scale := imageDstSize()/imageSrc0Size()
-	pos := texCoord
+	pos := srcPos
 	p0 := pos - 1/2.0/scale
 	p1 := pos + 1/2.0/scale
 

internal/builtinshader/shader.go

@@ -67,18 +67,18 @@ func adjustTexelForAddressRepeat(p vec2) vec2 {
 }
 {{end}}
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
 {{if eq .Filter .FilterNearest}}
 {{if eq .Address .AddressUnsafe}}
-	clr := imageSrc0UnsafeAt(texCoord)
+	clr := imageSrc0UnsafeAt(srcPos)
 {{else if eq .Address .AddressClampToZero}}
-	clr := imageSrc0At(texCoord)
+	clr := imageSrc0At(srcPos)
 {{else if eq .Address .AddressRepeat}}
-	clr := imageSrc0At(adjustTexelForAddressRepeat(texCoord))
+	clr := imageSrc0At(adjustTexelForAddressRepeat(srcPos))
 {{end}}
 {{else if eq .Filter .FilterLinear}}
-	p0 := texCoord - 1/2.0
-	p1 := texCoord + 1/2.0
+	p0 := srcPos - 1/2.0
+	p1 := srcPos + 1/2.0
 
 {{if eq .Address .AddressRepeat}}
 	p0 = adjustTexelForAddressRepeat(p0)

internal/graphics/shader.go

@@ -154,8 +154,8 @@ func imageSrc%[1]dAt(pos vec2) vec4 {
 	shaderSuffix += `
 var __projectionMatrix mat4
 
-func __vertex(position vec2, texCoord vec2, color vec4) (vec4, vec2, vec4) {
-	return __projectionMatrix * vec4(position, 0, 1), texCoord, color
+func __vertex(dstPos vec2, srcPos vec2, color vec4) (vec4, vec2, vec4) {
+	return __projectionMatrix * vec4(dstPos, 0, 1), srcPos, color
 }
 `
 	return shaderSuffix, nil

internal/restorable/shader.go

@@ -84,7 +84,7 @@ func init() {
 
 package main
 
-func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
+func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
 	return vec4(0)
 }`))
 		if err != nil {