paths.nim masks take blendMode for masking, tests, fixes and etc

pixie.nimble

@@ -1,4 +1,4 @@
-version     = "2.0.5"
+version     = "2.1.0"
 author      = "Andre von Houck and Ryan Oldenburg"
 description = "Full-featured 2d graphics library for Nim."
 license     = "MIT"

src/pixie/blends.nim

@@ -435,9 +435,6 @@ proc blendSubtractMask(backdrop, source: ColorRGBX): ColorRGBX =
   result.b = ((backdrop.b * a) div 255).uint8
   result.a = a.uint8
 
-proc blendIntersectMask(backdrop, source: ColorRGBX): ColorRGBX =
-  blendMask(backdrop, source)
-
 proc blendExcludeMask(backdrop, source: ColorRGBX): ColorRGBX =
   let a = max(backdrop.a, source.a).uint32 - min(backdrop.a, source.a)
   result.r = ((source.r * a) div 255).uint8
@@ -489,9 +486,6 @@ proc maskMask(backdrop, source: uint8): uint8 =
 proc maskSubtract(backdrop, source: uint8): uint8 =
   ((backdrop.uint32 * (255 - source)) div 255).uint8
 
-proc maskIntersect(backdrop, source: uint8): uint8 =
-  maskMask(backdrop, source)
-
 proc maskExclude(backdrop, source: uint8): uint8 =
   max(backdrop, source) - min(backdrop, source)
 
@@ -592,7 +586,7 @@ when defined(amd64) and not defined(pixieNoSimd):
       div255 = mm_set1_epi16(cast[int16](0x8081))
 
     var
-      sourceEven = mm_slli_epi16(mm_andnot_si128(oddMask, source), 8)
+      sourceEven = mm_slli_epi16(source, 8)
       sourceOdd = mm_and_si128(source, oddMask)
 
     let
@@ -600,7 +594,7 @@ when defined(amd64) and not defined(pixieNoSimd):
       oddK = mm_sub_epi16(v255high, sourceOdd)
 
     var
-      backdropEven = mm_slli_epi16(mm_andnot_si128(oddMask, backdrop), 8)
+      backdropEven = mm_slli_epi16(backdrop, 8)
       backdropOdd = mm_and_si128(backdrop, oddMask)
 
     # backdrop * k
@@ -625,11 +619,11 @@ when defined(amd64) and not defined(pixieNoSimd):
     let
       oddMask = mm_set1_epi16(cast[int16](0xff00))
       div255 = mm_set1_epi16(cast[int16](0x8081))
-      sourceEven = mm_slli_epi16(mm_andnot_si128(oddMask, source), 8)
+      sourceEven = mm_slli_epi16(source, 8)
       sourceOdd = mm_and_si128(source, oddMask)
 
     var
-      backdropEven = mm_slli_epi16(mm_andnot_si128(oddMask, backdrop), 8)
+      backdropEven = mm_slli_epi16(backdrop, 8)
       backdropOdd = mm_and_si128(backdrop, oddMask)
 
     # backdrop * source

src/pixie/paths.nim

@@ -1137,7 +1137,9 @@ iterator walk(
       # between zero and nonzero (or the last hit)
       count += winding
       continue
-    if at > 0:
+    if at <= 0:
+      count += winding
+      continue
     if shouldFill(windingRule, count):
       yield (prevAt, at, count)
     prevAt = at
@@ -1226,13 +1228,15 @@ proc computeCoverages(
           for j in i ..< fillStart + fillLen:
             coverages[j] += sampleCoverage
 
-proc clearUnsafe(image: Image, startX, startY, toX, toY: int) =
+proc clearUnsafe(target: Image | Mask, startX, startY, toX, toY: int) =
-  ## From startXY to toXY, exclusive, toXY is not cleared.
+  ## Clears data from [start, to).
-  image.data.fillUnsafe(
+  let
-    rgbx(0, 0, 0, 0),
+    start = target.dataIndex(startX, startY)
-    image.dataIndex(startX, startY),
+    len = target.dataIndex(toX, toY) - start
-    image.dataIndex(toX, toY) - image.dataIndex(startX, startY)
+  when type(target) is Image:
-  )
+    target.data.fillUnsafe(rgbx(0, 0, 0, 0), start, len)
+  else: # target is Mask
+    target.data.fillUnsafe(0, start, len)
 
 proc fillCoverage(
   image: Image,
@@ -1258,7 +1262,7 @@ proc fillCoverage(
         let
           index = image.dataIndex(x, y)
           eqZero = mm_cmpeq_epi16(coverage, mm_setzero_si128())
-        if mm_movemask_epi8(eqZero) != 0xffff:
+        if mm_movemask_epi8(eqZero) != 0xffff: # or blendMode == bmExcludeMask:
           # If the coverages are not all zero
           if mm_movemask_epi8(mm_cmpeq_epi32(coverage, first32)) == 0xffff:
             # Coverages are all 255
@@ -1294,6 +1298,8 @@ proc fillCoverage(
               image.data[index].addr,
               blenderSimd(backdrop, source)
             )
+        elif blendMode == bmMask:
+          mm_storeu_si128(image.data[index].addr, mm_setzero_si128())
         x += 4
 
   let blender = blendMode.blender()
@@ -1319,31 +1325,45 @@ proc fillCoverage(
   if blendMode == bmMask:
     image.clearUnsafe(0, y, startX, y)
 
-proc fillCoverage(mask: Mask, startX, y: int, coverages: seq[uint8]) =
+proc fillCoverage(
+  mask: Mask,
+  startX, y: int,
+  coverages: seq[uint8],
+  blendMode: BlendMode
+) =
   var x = startX
   when defined(amd64) and not defined(pixieNoSimd):
-    # When supported, SIMD blend as much as possible
+    if blendMode.hasSimdMasker():
-    let maskerSimd = bmNormal.maskerSimd()
+      let maskerSimd = blendMode.maskerSimd()
       for _ in countup(x, coverages.len - 16, 16):
         let
+          index = mask.dataIndex(x, y)
           coverage = mm_loadu_si128(coverages[x].unsafeAddr)
           eqZero = mm_cmpeq_epi16(coverage, mm_setzero_si128())
-      if mm_movemask_epi8(eqZero) != 0xffff:
+        if mm_movemask_epi8(eqZero) != 0xffff: # or blendMode == bmExcludeMask:
           # If the coverages are not all zero
-        let backdrop = mm_loadu_si128(mask.data[mask.dataIndex(x, y)].addr)
+          let backdrop = mm_loadu_si128(mask.data[index].addr)
           mm_storeu_si128(
-          mask.data[mask.dataIndex(x, y)].addr,
+            mask.data[index].addr,
             maskerSimd(backdrop, coverage)
           )
+        elif blendMode == bmMask:
+          mm_storeu_si128(mask.data[index].addr, mm_setzero_si128())
         x += 16
 
+  let masker = blendMode.masker()
   while x < mask.width:
     let coverage = coverages[x]
-    if coverage != 0:
+    if coverage != 0 or blendMode == bmExcludeMask:
       let backdrop = mask.getValueUnsafe(x, y)
-      mask.setValueUnsafe(x, y, blendAlpha(backdrop, coverage))
+      mask.setValueUnsafe(x, y, masker(backdrop, coverage))
+    elif blendMode == bmMask:
+      mask.setValueUnsafe(x, y, 0)
     inc x
 
+  if blendMode == bmMask:
+    mask.clearUnsafe(0, y, startX, y)
+
 proc fillHits(
   image: Image,
   rgbx: ColorRGBX,
@@ -1354,16 +1374,21 @@ proc fillHits(
   blendMode: BlendMode
 ) =
   let blender = blendMode.blender()
-  var x = 0
+  var filledTo: int
   for (prevAt, at, count) in hits.walk(numHits, windingRule, y, image.wh):
     let
       fillStart = prevAt.int
       fillLen = at.int - fillStart
-    if fillLen > 0:
+    if fillLen <= 0:
+      continue
+
+    filledTo = fillStart + fillLen
+
     if blendMode == bmNormal and rgbx.a == 255:
       fillUnsafe(image.data, rgbx, image.dataIndex(fillStart, y), fillLen)
-      else:
+      continue
-        x = fillStart
+
+    var x = fillStart
     when defined(amd64) and not defined(pixieNoSimd):
       if blendMode.hasSimdBlender():
         # When supported, SIMD blend as much as possible
@@ -1379,28 +1404,59 @@ proc fillHits(
             blenderSimd(backdrop, vColor)
           )
           x += 4
-        while x < fillStart + fillLen:
+
+    for x in x ..< fillStart + fillLen:
       let backdrop = image.getRgbaUnsafe(x, y)
       image.setRgbaUnsafe(x, y, blender(backdrop, rgbx))
-          inc x
 
   if blendMode == bmMask:
     image.clearUnsafe(0, y, startX, y)
-    image.clearUnsafe(x, y, image.width, y)
+    image.clearUnsafe(filledTo, y, image.width, y)
 
 proc fillHits(
   mask: Mask,
   startX, y: int,
   hits: seq[(float32, int16)],
   numHits: int,
-  windingRule: WindingRule
+  windingRule: WindingRule,
+  blendMode: BlendMode
 ) =
+  let masker = blendMode.masker()
+  var filledTo: int
   for (prevAt, at, count) in hits.walk(numHits, windingRule, y, mask.wh):
     let
       fillStart = prevAt.int
       fillLen = at.int - fillStart
-    if fillLen > 0:
+    if fillLen <= 0:
+      continue
+
+    filledTo = fillStart + fillLen
+
+    if blendMode == bmNormal:
       fillUnsafe(mask.data, 255, mask.dataIndex(fillStart, y), fillLen)
+      continue
+
+    var x = fillStart
+    when defined(amd64) and not defined(pixieNoSimd):
+      if blendMode.hasSimdMasker():
+        let
+          maskerSimd = blendMode.maskerSimd()
+          vValue = mm_set1_epi8(cast[int8](255))
+        for _ in countup(fillStart, fillLen - 16, 16):
+          let backdrop = mm_loadu_si128(mask.data[mask.dataIndex(x, y)].addr)
+          mm_storeu_si128(
+            mask.data[mask.dataIndex(x, y)].addr,
+            maskerSimd(backdrop, vValue)
+          )
+          x += 16
+
+    for x in x ..< fillStart + fillLen:
+      let backdrop = mask.getValueUnsafe(x, y)
+      mask.setValueUnsafe(x, y, masker(backdrop, 255))
+
+  if blendMode == bmMask:
+    mask.clearUnsafe(0, y, startX, y)
+    mask.clearUnsafe(filledTo, y, mask.width, y)
 
 proc fillShapes(
   image: Image,
@@ -1460,7 +1516,12 @@ proc fillShapes(
     image.clearUnsafe(0, 0, 0, startY)
     image.clearUnsafe(0, pathHeight, 0, image.height)
 
-proc fillShapes(mask: Mask, shapes: seq[seq[Vec2]], windingRule: WindingRule) =
+proc fillShapes(
+  mask: Mask,
+  shapes: seq[seq[Vec2]],
+  windingRule: WindingRule,
+  blendMode: BlendMode
+) =
   # Figure out the total bounds of all the shapes,
   # rasterize only within the total bounds
   let
@@ -1469,8 +1530,7 @@ proc fillShapes(mask: Mask, shapes: seq[seq[Vec2]], windingRule: WindingRule) =
     bounds = computePixelBounds(segments)
     startX = max(0, bounds.x.int)
     startY = max(0, bounds.y.int)
-    stopY = min(mask.height, (bounds.y + bounds.h).int)
+    pathHeight = min(mask.height, (bounds.y + bounds.h).int)
-    pathHeight = stopY - startY
     partitioning = partitionSegments(segments, startY, pathHeight)
 
   var
@@ -1478,7 +1538,7 @@ proc fillShapes(mask: Mask, shapes: seq[seq[Vec2]], windingRule: WindingRule) =
     hits = newSeq[(float32, int16)](4)
     numHits: int
 
-  for y in startY ..< stopY:
+  for y in startY ..< pathHeight:
     computeCoverages(
       coverages,
       hits,
@@ -1490,9 +1550,13 @@ proc fillShapes(mask: Mask, shapes: seq[seq[Vec2]], windingRule: WindingRule) =
       windingRule
     )
     if aa:
-      mask.fillCoverage(startX, y, coverages)
+      mask.fillCoverage(startX, y, coverages, blendMode)
     else:
-      mask.fillHits(startX, y, hits, numHits, windingRule)
+      mask.fillHits(startX, y, hits, numHits, windingRule, blendMode)
+
+  if blendMode == bmMask:
+    mask.clearUnsafe(0, 0, 0, startY)
+    mask.clearUnsafe(0, pathHeight, 0, mask.height)
 
 proc miterLimitToAngle*(limit: float32): float32 =
   ## Converts miter-limit-ratio to miter-limit-angle.
@@ -1668,12 +1732,13 @@ proc fillPath*(
   mask: Mask,
   path: SomePath,
   transform: Vec2 | Mat3 = vec2(),
-  windingRule = wrNonZero
+  windingRule = wrNonZero,
+  blendMode = bmNormal
 ) =
   ## Fills a path.
   var shapes = parseSomePath(path, true, transform.pixelScale())
   shapes.transform(transform)
-  mask.fillShapes(shapes, windingRule)
+  mask.fillShapes(shapes, windingRule, blendMode)
 
 proc fillPath*(
   image: Image,
@@ -1721,7 +1786,8 @@ proc strokePath*(
   lineCap = lcButt,
   lineJoin = ljMiter,
   miterLimit = defaultMiterLimit,
-  dashes: seq[float32] = @[]
+  dashes: seq[float32] = @[],
+  blendMode = bmNormal
 ) =
   ## Strokes a path.
   var strokeShapes = strokeShapes(
@@ -1733,7 +1799,7 @@ proc strokePath*(
     dashes
   )
   strokeShapes.transform(transform)
-  mask.fillShapes(strokeShapes, wrNonZero)
+  mask.fillShapes(strokeShapes, wrNonZero, blendMode)
 
 proc strokePath*(
   image: Image,

tests/test_paths.nim

@@ -415,23 +415,23 @@ block:
 block:
   let mask = newMask(100, 100)
   mask.fillPath("M 10 10 H 60 V 60 H 10 z")
-  mask.fillPath("M 30 30 H 80 V 80 H 30 z")#, blendMode = bmExcludeMask)
+  mask.fillPath("M 30 30 H 80 V 80 H 30 z", blendMode = bmExcludeMask)
   writeFile("tests/images/paths/maskRectExcludeMask.png", mask.encodePng())
 
 block:
   let mask = newMask(100, 100)
   mask.fillPath("M 10.1 10.1 H 60.1 V 60.1 H 10.1 z")
-  mask.fillPath("M 30.1 30.1 H 80.1 V 80.1 H 30.1 z")#, blendMode = bmExcludeMask)
+  mask.fillPath("M 30.1 30.1 H 80.1 V 80.1 H 30.1 z", blendMode = bmExcludeMask)
   writeFile("tests/images/paths/maskRectExcludeMaskAA.png", mask.encodePng())
 
 block:
   let mask = newMask(100, 100)
   mask.fillPath("M 10 10 H 60 V 60 H 10 z")
-  mask.fillPath("M 30 30 H 80 V 80 H 30 z")#, blendMode = bmMask)
+  mask.fillPath("M 30 30 H 80 V 80 H 30 z", blendMode = bmMask)
   writeFile("tests/images/paths/maskRectMask.png", mask.encodePng())
 
 block:
   let mask = newMask(100, 100)
   mask.fillPath("M 10.1 10.1 H 60.1 V 60.1 H 10.1 z")
-  mask.fillPath("M 30.1 30.1 H 80.1 V 80.1 H 30.1 z")#, blendMode = bmMask)
+  mask.fillPath("M 30.1 30.1 H 80.1 V 80.1 H 30.1 z", blendMode = bmMask)
   writeFile("tests/images/paths/maskRectMaskAA.png", mask.encodePng())