added sourceBox parameter to resizeInto in RasterYuv420Semiplanar

source/draw/RasterYuv420Semiplanar.ooc

@@ -92,30 +92,36 @@ RasterYuv420Semiplanar: class extends RasterImage {
 		}
 		result
 	}
-	resizeInto: func (target: This) {
+	resizeInto: func (target: This, sourceBox := IntBox2D new()) {
+		if (sourceBox hasZeroArea)
+			sourceBox = IntBox2D new(this size)
+		version(safe)
+			raise(sourceBox intersection(IntBox2D new(this size)) != sourceBox, "invalid source box in RasterYuv420Semiplanar resizeInto !")
+		thisSizeY := sourceBox height
+		thisSizeX := sourceBox width
 		thisYBuffer := this y buffer pointer
 		targetYBuffer := target y buffer pointer
 		for (row in 0 .. target size y) {
-			srcRow := (this size y * row) / target size y
+			srcRow := (thisSizeY * row) / target size y + sourceBox top
 			thisStride := srcRow * this y stride
 			targetStride := row * target y stride
 			for (column in 0 .. target size x) {
-				srcColumn := (this size x * column) / target size x
+				srcColumn := (thisSizeX * column) / target size x + sourceBox left
 				targetYBuffer[column + targetStride] = thisYBuffer[srcColumn + thisStride]
 			}
 		}
 		targetSizeHalf := target size / 2
-		thisSizeHalf := this size / 2
+		thisSizeHalf := sourceBox size / 2
 		thisUvBuffer := this uv buffer pointer as ColorUv*
 		targetUvBuffer := target uv buffer pointer as ColorUv*
 		if (target size y isOdd)
 			targetSizeHalf = IntVector2D new(targetSizeHalf x, targetSizeHalf y + 1)
 		for (row in 0 .. targetSizeHalf y) {
-			srcRow := (thisSizeHalf y * row) / targetSizeHalf y
+			srcRow := (thisSizeHalf y * row) / targetSizeHalf y + sourceBox top / 2
 			thisStride := srcRow * this uv stride / 2
 			targetStride := row * target uv stride / 2
 			for (column in 0 .. targetSizeHalf x) {
-				srcColumn := (thisSizeHalf x * column) / targetSizeHalf x
+				srcColumn := (thisSizeHalf x * column) / targetSizeHalf x + sourceBox left / 2
 				targetUvBuffer[column + targetStride] = thisUvBuffer[srcColumn + thisStride]
 			}
 		}

test/draw/RasterYuv420SemiplanarTest.ooc

@@ -122,6 +122,16 @@ RasterYuv420SemiplanarTest: class extends Fixture {
 			(resized, source) referenceCount decrease()
 			output free()
 		})
+		this add("resize (with box)", func {
+			source := RasterYuv420Semiplanar open(this _inputPath)
+			box := IntBox2D new(0, source height / 2, source width, source height / 2)
+			target := RasterYuv420Semiplanar new(source size)
+			source resizeInto(target, box)
+			output := "test/draw/output/RasterYuv420SemiplanarTest_lowerHalfResized.png"
+			target save(output)
+			(target, source) referenceCount decrease()
+			output free()
+		})
 	}
 	free: override func {
 		(this _inputPath, this _inputOddWidth, this _inputOddHeight) free()