From 06f211f7353786ad93850a1773172f164ebc66ff Mon Sep 17 00:00:00 2001
From: Ryan Oldenburg <ryan@guzba.com>
Date: Tue, 30 Nov 2021 16:00:30 -0600
Subject: [PATCH] path fillImage

---
 experiments/benchmark_cairo.nim | 23 +++++++++----
 src/pixie/paths.nim             | 60 +++++++++++++++++++++++++++++++--
 2 files changed, 73 insertions(+), 10 deletions(-)

diff --git a/experiments/benchmark_cairo.nim b/experiments/benchmark_cairo.nim
index 17ef2ac..5e1acb9 100644
--- a/experiments/benchmark_cairo.nim
+++ b/experiments/benchmark_cairo.nim
@@ -151,12 +151,17 @@ block:
     ctx = surface.create()
 
   timeIt "cairo4":
-    ctx.setSourceRgba(1, 1, 1, 0.25)
+    ctx.setSourceRgba(0, 0, 0, 0)
     let operator = ctx.getOperator()
     ctx.setOperator(OperatorSource)
     ctx.paint()
     ctx.setOperator(operator)
 
+  # timeIt "cairo4":
+  #   let
+  #     surface = imageSurfaceCreate(FORMAT_ARGB32, 1000, 1000)
+  #     ctx = surface.create()
+
     ctx.setSourceRgba(1, 0, 0, 0.5)
 
     ctx.newPath()
@@ -169,10 +174,10 @@ block:
 
   # discard surface.writeToPng("cairo4.png")
 
-  let a = newImage(1000, 1000)
-
+  var a: Image
+  a = newImage(1000, 1000)
   timeIt "pixie4":
-    a.fill(rgba(255, 255, 255, 63))
+    # a = newImage(1000, 1000)
 
     let p = newPath()
     p.moveTo(shapes[0][0])
@@ -185,10 +190,8 @@ block:
 
   # doDiff(readImage("cairo4.png"), a, "4")
 
-  let mask = newMask(1000, 1000)
-
   timeIt "pixie4 mask":
-    mask.fill(63)
+    let mask = newMask(1000, 1000)
 
     let p = newPath()
     p.moveTo(shapes[0][0])
@@ -196,3 +199,9 @@ block:
       for v in shape:
         p.lineTo(v)
     mask.fillPath(p)
+
+  var tmp: Image
+  timeIt "pixie fillImage":
+    tmp = path.fillImage(1000, 1000, rgba(255, 0, 0, 127))
+
+  # tmp.writeFile("tmp.png")
diff --git a/src/pixie/paths.nim b/src/pixie/paths.nim
index a1307d8..73c523d 100644
--- a/src/pixie/paths.nim
+++ b/src/pixie/paths.nim
@@ -1327,14 +1327,14 @@ proc fillCoverage(
         oddMask = mm_set1_epi16(cast[int16](0xff00))
         div255 = mm_set1_epi16(cast[int16](0x8081))
         vec255 = mm_set1_epi32(cast[int32](uint32.high))
-        zeroVec = mm_setzero_si128()
+        vecZero = mm_setzero_si128()
         colorVec = mm_set1_epi32(cast[int32](rgbx))
       for _ in 0 ..< coverages.len div 16:
         let
           index = image.dataIndex(x, y)
           coverageVec = mm_loadu_si128(coverages[x - startX].unsafeAddr)
 
-        if mm_movemask_epi8(mm_cmpeq_epi16(coverageVec, zeroVec)) != 0xffff:
+        if mm_movemask_epi8(mm_cmpeq_epi16(coverageVec, vecZero)) != 0xffff:
           # If the coverages are not all zero
           if mm_movemask_epi8(mm_cmpeq_epi32(coverageVec, vec255)) == 0xffff:
             # If the coverages are all 255
@@ -1393,7 +1393,7 @@ proc fillCoverage(
 
         elif blendMode == bmMask:
           for i in 0 ..< 4:
-            mm_storeu_si128(image.data[index + i * 4].addr, zeroVec)
+            mm_storeu_si128(image.data[index + i * 4].addr, vecZero)
 
         x += 16
 
@@ -2454,5 +2454,59 @@ else:
       image.clearUnsafe(0, 0, 0, startY)
       image.clearUnsafe(0, pathHeight, 0, image.height)
 
+proc fillImage*(path: SomePath, width, height: int, color: SomeColor): Image =
+  result = newImage(width, height)
+
+  let mask = newMask(width, height)
+  mask.fillPath(path)
+
+  let rgbx = color.rgbx()
+
+  var i: int
+  when defined(amd64) and not defined(pixieNoSimd):
+    let
+      colorVec = mm_set1_epi32(cast[int32](rgbx))
+      oddMask = mm_set1_epi16(cast[int16](0xff00))
+      div255 = mm_set1_epi16(cast[int16](0x8081))
+      vec255 = mm_set1_epi32(cast[int32](uint32.high))
+      vecZero = mm_setzero_si128()
+      colorVecEven = mm_slli_epi16(colorVec, 8)
+      colorVecOdd = mm_and_si128(colorVec, oddMask)
+      iterations = result.data.len div 16
+    for _ in 0 ..< iterations:
+      var coverageVec = mm_loadu_si128(mask.data[i].addr)
+      if mm_movemask_epi8(mm_cmpeq_epi16(coverageVec, vecZero)) != 0xffff:
+        if mm_movemask_epi8(mm_cmpeq_epi32(coverageVec, vec255)) == 0xffff:
+          for q in [0, 4, 8, 12]:
+            mm_storeu_si128(result.data[i + q].addr, colorVec)
+        else:
+          for q in [0, 4, 8, 12]:
+            var unpacked = unpackAlphaValues(coverageVec)
+            # Shift the coverages from `a` to `g` and `a` for multiplying
+            unpacked = mm_or_si128(unpacked, mm_srli_epi32(unpacked, 16))
+
+            var
+              sourceEven = mm_mulhi_epu16(colorVecEven, unpacked)
+              sourceOdd = mm_mulhi_epu16(colorVecOdd, unpacked)
+            sourceEven = mm_srli_epi16(mm_mulhi_epu16(sourceEven, div255), 7)
+            sourceOdd = mm_srli_epi16(mm_mulhi_epu16(sourceOdd, div255), 7)
+
+            mm_storeu_si128(
+              result.data[i + q].addr,
+              mm_or_si128(sourceEven, mm_slli_epi16(sourceOdd, 8))
+            )
+
+            coverageVec = mm_srli_si128(coverageVec, 4)
+
+      i += 16
+
+  let channels = [rgbx.r.uint32, rgbx.g.uint32, rgbx.b.uint32, rgbx.a.uint32]
+  for i in i ..< result.data.len:
+    let coverage = mask.data[i]
+    result.data[i].r = ((channels[0] * coverage) div 255).uint8
+    result.data[i].g = ((channels[1] * coverage) div 255).uint8
+    result.data[i].b = ((channels[2] * coverage) div 255).uint8
+    result.data[i].a = ((channels[3] * coverage) div 255).uint8
+
 when defined(release):
   {.pop.}