diff --git a/src/pixie/paths.nim b/src/pixie/paths.nim
index 1f6db0d..48b2229 100644
--- a/src/pixie/paths.nim
+++ b/src/pixie/paths.nim
@@ -45,7 +45,7 @@ type
startY, partitionHeight: uint32
const
- epsilon: float32 = 0.0001 * PI ## Tiny value used for some computations.
+ epsilon = 0.0001 * PI ## Tiny value used for some computations.
defaultMiterLimit*: float32 = 4
when defined(release):
@@ -651,7 +651,7 @@ proc commandsToShapes(
prevCommandKind = Move
prevCtrl, prevCtrl2: Vec2
- let errorMargin = 0.2 / pixelScale
+ let errorMargin = pow(0.2.float32 / pixelScale, 2)
proc addSegment(shape: var seq[Vec2], at, to: Vec2) =
# Don't add any 0 length lines
@@ -669,27 +669,29 @@ proc commandsToShapes(
(1 - t) * 3 * pow(t, 2) * ctrl2 +
pow(t, 3) * to
- var prev = at
-
- proc discretize(shape: var seq[Vec2], i, steps: int) =
- # Closure captures at, ctrl1, ctrl2, to and prev
+ var
+ t: float32 # Where we are at on the curve from [0, 1]
+ step = 1.float32 # How far we want to try to move along the curve
+ prev = at
+ next = compute(at, ctrl1, ctrl2, to, t + step)
+ halfway = compute(at, ctrl1, ctrl2, to, t + step / 2)
+ while true:
let
- tPrev = (i - 1).float32 / steps.float32
- t = i.float32 / steps.float32
- next = compute(at, ctrl1, ctrl2, to, t)
- halfway = compute(at, ctrl1, ctrl2, to, tPrev + (t - tPrev) / 2)
midpoint = (prev + next) / 2
- error = (midpoint - halfway).length
-
- if error >= errorMargin:
- # Error too large, double precision for this step
- shape.discretize(i * 2 - 1, steps * 2)
- shape.discretize(i * 2, steps * 2)
+ error = (midpoint - halfway).lengthSq
+ if error > errorMargin:
+ next = halfway
+ halfway = compute(at, ctrl1, ctrl2, to, t + step / 4)
+ step /= 2
else:
shape.addSegment(prev, next)
+ t += step
+ if t == 1:
+ break
prev = next
-
- shape.discretize(1, 1)
+ step = min(step * 2, 1 - t) # Optimistically attempt larger steps
+ next = compute(at, ctrl1, ctrl2, to, t + step)
+ halfway = compute(at, ctrl1, ctrl2, to, t + step / 2)
proc addQuadratic(shape: var seq[Vec2], at, ctrl, to: Vec2) =
## Adds quadratic segments to shape.
@@ -698,27 +700,34 @@ proc commandsToShapes(
2 * (1 - t) * t * ctrl +
pow(t, 2) * to
- var prev = at
-
- proc discretize(shape: var seq[Vec2], i, steps: int) =
- # Closure captures at, ctrl, to and prev
+ var
+ t: float32 # Where we are at on the curve from [0, 1]
+ step = 1.float32 # How far we want to try to move along the curve
+ prev = at
+ next = compute(at, ctrl, to, t + step)
+ halfway = compute(at, ctrl, to, t + step / 2)
+ halfStepping = false
+ while true:
let
- tPrev = (i - 1).float32 / steps.float32
- t = i.float32 / steps.float32
- next = compute(at, ctrl, to, t)
- halfway = compute(at, ctrl, to, tPrev + (t - tPrev) / 2)
midpoint = (prev + next) / 2
- error = (midpoint - halfway).length
-
- if error >= errorMargin:
- # Error too large, double precision for this step
- shape.discretize(i * 2 - 1, steps * 2)
- shape.discretize(i * 2, steps * 2)
+ error = (midpoint - halfway).lengthSq
+ if error > errorMargin:
+ next = halfway
+ halfway = compute(at, ctrl, to, t + step / 4)
+ step /= 2
+ halfStepping = true
else:
shape.addSegment(prev, next)
+ t += step
+ if t == 1:
+ break
prev = next
-
- shape.discretize(1, 1)
+ if halfStepping:
+ step = min(step, 1 - t)
+ else:
+ step = min(step * 2, 1 - t) # Optimistically attempt larger steps
+ next = compute(at, ctrl, to, t + step)
+ halfway = compute(at, ctrl, to, t + step / 2)
proc addArc(
shape: var seq[Vec2],
@@ -808,28 +817,37 @@ proc commandsToShapes(
result = vec2(cos(a) * arc.radii.x, sin(a) * arc.radii.y)
result = arc.rotMat * result + arc.center
- var prev = at
+ let arc = endpointToCenterArcParams(at, radii, rotation, large, sweep, to)
- proc discretize(shape: var seq[Vec2], arc: ArcParams, i, steps: int) =
+ var
+ t: float32 # Where we are at on the curve from [0, 1]
+ step = 1.float32 # How far we want to try to move along the curve
+ prev = at
+ while t != 1:
let
- step = arc.delta / steps.float32
- aPrev = arc.theta + step * (i - 1).float32
- a = arc.theta + step * i.float32
+ aPrev = arc.theta + arc.delta * t
+ a = arc.theta + arc.delta * (t + step)
next = arc.compute(a)
halfway = arc.compute(aPrev + (a - aPrev) / 2)
midpoint = (prev + next) / 2
- error = (midpoint - halfway).length
-
- if error >= errorMargin:
- # Error too large, try again with doubled precision
- shape.discretize(arc, i * 2 - 1, steps * 2)
- shape.discretize(arc, i * 2, steps * 2)
+ error = (midpoint - halfway).lengthSq
+ if error > errorMargin:
+ let
+ quarterway = arc.compute(aPrev + (a - aPrev) / 4)
+ midpoint = (prev + halfway) / 2
+ halfwayError = (midpoint - quarterway).lengthSq
+ if halfwayError < errorMargin:
+ shape.addSegment(prev, halfway)
+ prev = halfway
+ t += step / 2
+ step = min(step / 2, 1 - t) # Assume next steps hould be the same size
+ else:
+ step = step / 4 # We know a half-step is too big
else:
shape.addSegment(prev, next)
prev = next
-
- let arc = endpointToCenterArcParams(at, radii, rotation, large, sweep, to)
- shape.discretize(arc, 1, 1)
+ t += step
+ step = min(step * 2, 1 - t) # Optimistically attempt larger steps
for command in path.commands:
if command.numbers.len != command.kind.parameterCount():
@@ -1214,7 +1232,7 @@ proc computeCoverage(
let
quality = if aa: 5 else: 1 # Must divide 255 cleanly (1, 3, 5, 15, 17, 51, 85)
sampleCoverage = (255 div quality).uint8
- offset = 1 / quality.float32
+ offset = 1 / quality.float64
initialOffset = offset / 2 + epsilon
if aa: # Coverage is only used for anti-aliasing
@@ -1224,7 +1242,7 @@ proc computeCoverage(
let
partitionIndex = partitioning.getIndexForY(y)
partitionEntryCount = partitioning.partitions[partitionIndex].len
- var yLine = y.float32 + initialOffset - offset
+ var yLine = y.float64 + initialOffset - offset
for m in 0 ..< quality:
yLine += offset
numHits = 0
@@ -1813,8 +1831,7 @@ proc fillPath*(
var shapes = parseSomePath(path, true, transform.pixelScale())
shapes.transform(transform)
var color = paint.color
- if paint.opacity != 1:
- color.a *= paint.opacity
+ color.a *= paint.opacity
image.fillShapes(shapes, color, windingRule, paint.blendMode)
return
@@ -1897,8 +1914,7 @@ proc strokePath*(
)
strokeShapes.transform(transform)
var color = paint.color
- if paint.opacity != 1:
- color.a *= paint.opacity
+ color.a *= paint.opacity
image.fillShapes(strokeShapes, color, wrNonZero, paint.blendMode)
return
diff --git a/tests/benchmark_svg.nim b/tests/benchmark_svg.nim
index a17351d..c158d6d 100644
--- a/tests/benchmark_svg.nim
+++ b/tests/benchmark_svg.nim
@@ -3,4 +3,4 @@ import benchy, pixie/fileformats/svg
let data = readFile("tests/fileformats/svg/Ghostscript_Tiger.svg")
timeIt "svg decode":
- keep decodeSvg(data)
+ discard decodeSvg(data)