From cddfe43315662a18e9282df928d39835c3fc90bf Mon Sep 17 00:00:00 2001
From: Ryan Oldenburg <guzba8@gmail.com>
Date: Fri, 4 Dec 2020 14:09:08 -0600
Subject: [PATCH] scanLineHits a bunch faster
---
src/pixie/paths.nim | 42 ++++++++++++++++++++++++------------------
tests/test_svg.nim | 5 ++++-
2 files changed, 28 insertions(+), 19 deletions(-)
diff --git a/src/pixie/paths.nim b/src/pixie/paths.nim
index f9d3b0a..cccc626 100644
--- a/src/pixie/paths.nim
+++ b/src/pixie/paths.nim
@@ -599,32 +599,38 @@ proc fillPolygons*(
proc scanLineHits(
polys: seq[seq[Vec2]],
hits: var seq[(float32, bool)],
+ size: Vec2,
y: int,
shiftY: float32
- ) =
+ ) {.inline.} =
hits.setLen(0)
- var yLine = (float32(y) + ep) + shiftY
- var scan = Segment(at: vec2(-10000, yLine), to: vec2(100000, yLine))
+
+ let
+ yLine = (float32(y) + ep) + shiftY
+ scan = Segment(at: vec2(-10000, yLine), to: vec2(100000, yLine))
for poly in polys:
- for (at, to) in poly.zipwise:
- let line = Segment(at: at, to: to)
+ for e in poly.zipwise:
+ let line = cast[Segment](e)
var at: Vec2
if line.intersects(scan, at):
- let winding = line.at.y > line.to.y
- let x = at.x.clamp(0, size.x)
+ let
+ winding = line.at.y > line.to.y
+ x = at.x.clamp(0, size.x)
hits.add((x, winding))
hits.sort(proc(a, b: (float32, bool)): int = cmp(a[0], b[0]))
- var hits: seq[(float32, bool)]
-
- var alphas = newSeq[float32](result.width)
+ var
+ hits = newSeq[(float32, bool)]()
+ alphas = newSeq[float32](result.width)
for y in 0 ..< result.height:
- for x in 0 ..< result.width:
- alphas[x] = 0
+ # Reset alphas for this row.
+ zeroMem(alphas[0].addr, alphas.len * 4)
+
+ # Do scanlines for this row.
for m in 0 ..< quality:
- polys.scanLineHits(hits, y, float32(m)/float32(quality))
+ polys.scanLineHits(hits, size, y, float32(m) / float32(quality))
if hits.len == 0:
continue
var
@@ -633,12 +639,11 @@ proc fillPolygons*(
for x in 0 ..< result.width:
var penEdge = penFill
while true:
- if curHit >= hits.len:
+ if curHit >= hits.len or x != hits[curHit][0].int:
break
- if x != hits[curHit][0].int:
- break
- let cover = hits[curHit][0] - x.float32
- let winding = hits[curHit][1]
+ let
+ cover = hits[curHit][0] - x.float32
+ winding = hits[curHit][1]
if winding == false:
penFill += 1.0
penEdge += 1.0 - cover
@@ -647,6 +652,7 @@ proc fillPolygons*(
penEdge -= 1.0 - cover
inc curHit
alphas[x] += penEdge
+
for x in 0 ..< result.width:
let a = clamp(abs(alphas[x]) / float32(quality), 0.0, 1.0)
var colorWithAlpha = color
diff --git a/tests/test_svg.nim b/tests/test_svg.nim
index e9a63ed..d9b2361 100644
--- a/tests/test_svg.nim
+++ b/tests/test_svg.nim
@@ -3,4 +3,7 @@ import pixie/fileformats/svg, pixie
let
original = readFile("tests/images/svg/Ghostscript_Tiger.svg")
image = decodeSvg(original)
-image.writeFile("tests/images/svg/Ghostscript_Tiger.png")
+ gold = readImage("tests/images/svg/Ghostscript_Tiger.png")
+
+doAssert image.data == gold.data
+# image.writeFile("tests/images/svg/Ghostscript_Tiger.png")