move pixieSweeps
This commit is contained in:
Ryan Oldenburg
parent
152be5c902
commit
2e163e6e6c
426
experiments/sweeps4.nim
Normal file
426
experiments/sweeps4.nim
Normal file
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@ -0,0 +1,426 @@
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when defined(pixieSweeps):
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import algorithm
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proc pixelCover(a0, b0: Vec2): float32 =
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## Returns the amount of area a given segment sweeps to the right
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## in a [0,0 to 1,1] box.
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var
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a = a0
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b = b0
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aI: Vec2
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bI: Vec2
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area: float32 = 0.0
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if (a.x < 0 and b.x < 0) or # Both to the left.
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(a.x == b.x): # Vertical line
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# Area of the rectangle:
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return (1 - clamp(a.x, 0, 1)) * (min(b.y, 1) - max(a.y, 0))
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else:
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# y = mm*x + bb
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let
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mm: float32 = (b.y - a.y) / (b.x - a.x)
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bb: float32 = a.y - mm * a.x
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if a.x >= 0 and a.x <= 1 and a.y >= 0 and a.y <= 1:
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# A is in pixel bounds.
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aI = a
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else:
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aI = vec2((0 - bb) / mm, 0)
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if aI.x < 0:
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let y = mm * 0 + bb
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# Area of the extra rectangle.
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area += (min(bb, 1) - max(a.y, 0)).clamp(0, 1)
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aI = vec2(0, y.clamp(0, 1))
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elif aI.x > 1:
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let y = mm * 1 + bb
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aI = vec2(1, y.clamp(0, 1))
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if b.x >= 0 and b.x <= 1 and b.y >= 0 and b.y <= 1:
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# B is in pixel bounds.
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bI = b
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else:
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bI = vec2((1 - bb) / mm, 1)
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if bI.x < 0:
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let y = mm * 0 + bb
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# Area of the extra rectangle.
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area += (min(b.y, 1) - max(bb, 0)).clamp(0, 1)
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bI = vec2(0, y.clamp(0, 1))
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elif bI.x > 1:
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let y = mm * 1 + bb
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bI = vec2(1, y.clamp(0, 1))
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area += ((1 - aI.x) + (1 - bI.x)) / 2 * (bI.y - aI.y)
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return area
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proc intersectsInner*(a, b: Segment, at: var Vec2): bool {.inline.} =
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## Checks if the a segment intersects b segment.
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## If it returns true, at will have point of intersection
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let
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s1 = a.to - a.at
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s2 = b.to - b.at
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denominator = (-s2.x * s1.y + s1.x * s2.y)
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s = (-s1.y * (a.at.x - b.at.x) + s1.x * (a.at.y - b.at.y)) / denominator
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t = (s2.x * (a.at.y - b.at.y) - s2.y * (a.at.x - b.at.x)) / denominator
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if s > 0 and s < 1 and t > 0 and t < 1:
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at = a.at + (t * s1)
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return true
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type
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Trapezoid = object
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nw, ne, se, sw: Vec2
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SweepLine = object
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#m, x, b: float32
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atx, tox: float32
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winding: int16
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proc toLine(s: (Segment, int16)): SweepLine =
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var line = SweepLine()
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line.atx = s[0].at.x
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line.tox = s[0].to.x
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# y = mx + b
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# line.m = (s.at.y - s.to.y) / (s.at.x - s.to.x)
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# line.b = s.at.y - line.m * s.at.x
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line.winding = s[1]
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return line
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proc intersectsYLine(
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y: float32, s: Segment, atx: var float32
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): bool {.inline.} =
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let
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s2y = s.to.y - s.at.y
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denominator = -s2y
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numerator = s.at.y - y
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u = numerator / denominator
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if u >= 0 and u <= 1:
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let at = s.at + (u * vec2(s.to.x - s.at.x, s2y))
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atx = at.x
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return true
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proc binaryInsert(arr: var seq[float32], v: float32) =
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if arr.len == 0:
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arr.add(v)
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return
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var
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L = 0
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R = arr.len - 1
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while L < R:
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let m = (L + R) div 2
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if arr[m] ~= v:
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return
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elif arr[m] < v:
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L = m + 1
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else: # arr[m] > v:
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R = m - 1
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if arr[L] ~= v:
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return
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elif arr[L] > v:
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arr.insert(v, L)
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else:
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arr.insert(v, L + 1)
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proc sortSegments(segments: var seq[(Segment, int16)], inl, inr: int) =
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## Quicksort + insertion sort, in-place and faster than standard lib sort.
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let n = inr - inl + 1
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if n < 32: # Use insertion sort for the rest
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for i in inl + 1 .. inr:
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var
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j = i - 1
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k = i
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while j >= 0 and segments[j][0].at.y > segments[k][0].at.y:
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swap(segments[j + 1], segments[j])
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dec j
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dec k
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return
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var
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l = inl
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r = inr
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let p = segments[l + n div 2][0].at.y
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while l <= r:
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if segments[l][0].at.y < p:
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inc l
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elif segments[r][0].at.y > p:
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dec r
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else:
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swap(segments[l], segments[r])
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inc l
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dec r
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sortSegments(segments, inl, r)
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sortSegments(segments, l, inr)
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proc sortSweepLines(segments: var seq[SweepLine], inl, inr: int) =
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## Quicksort + insertion sort, in-place and faster than standard lib sort.
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proc avg(line: SweepLine): float32 {.inline.} =
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(line.tox + line.atx) / 2.float32
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let n = inr - inl + 1
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if n < 32: # Use insertion sort for the rest
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for i in inl + 1 .. inr:
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var
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j = i - 1
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k = i
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while j >= 0 and segments[j].avg > segments[k].avg:
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swap(segments[j + 1], segments[j])
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dec j
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dec k
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return
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var
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l = inl
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r = inr
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let p = segments[l + n div 2].avg
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while l <= r:
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if segments[l].avg < p:
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inc l
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elif segments[r].avg > p:
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dec r
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else:
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swap(segments[l], segments[r])
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inc l
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dec r
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sortSweepLines(segments, inl, r)
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sortSweepLines(segments, l, inr)
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proc fillShapes(
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image: Image,
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shapes: seq[seq[Vec2]],
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color: SomeColor,
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windingRule: WindingRule,
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blendMode: BlendMode
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) =
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let rgbx = color.rgbx
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var segments = shapes.shapesToSegments()
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let
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bounds = computeBounds(segments).snapToPixels()
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startX = max(0, bounds.x.int)
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if segments.len == 0 or bounds.w.int == 0 or bounds.h.int == 0:
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return
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# const q = 1/10
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# for i in 0 ..< segments.len:
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# segments[i][0].at.x = quantize(segments[i][0].at.x, q)
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# segments[i][0].at.y = quantize(segments[i][0].at.y, q)
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# segments[i][0].to.x = quantize(segments[i][0].to.x, q)
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# segments[i][0].to.y = quantize(segments[i][0].to.y, q)
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# Create sorted segments.
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segments.sortSegments(0, segments.high)
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# Compute cut lines
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var cutLines: seq[float32]
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for s in segments:
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cutLines.binaryInsert(s[0].at.y)
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cutLines.binaryInsert(s[0].to.y)
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var
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# Dont add bottom cutLine.
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sweeps = newSeq[seq[SweepLine]](cutLines.len - 1)
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lastSeg = 0
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i = 0
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while i < sweeps.len:
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if lastSeg < segments.len:
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while segments[lastSeg][0].at.y == cutLines[i]:
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let s = segments[lastSeg]
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if s[0].to.y != cutLines[i + 1]:
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var atx: float32
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var seg = s[0]
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for j in i ..< sweeps.len:
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let y = cutLines[j + 1]
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if intersectsYLine(y, seg, atx):
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sweeps[j].add(toLine((segment(seg.at, vec2(atx, y)), s[1])))
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seg = segment(vec2(atx, y), seg.to)
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else:
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if seg.at.y != seg.to.y:
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sweeps[j].add(toLine(s))
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break
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else:
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sweeps[i].add(toLine(s))
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inc lastSeg
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if lastSeg >= segments.len:
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break
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inc i
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# i = 0
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# while i < sweeps.len:
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# # TODO: Maybe finds all cuts first, add them to array, cut all lines at once.
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# var crossCuts: seq[float32]
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# # echo i, " cut?"
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# for aIndex in 0 ..< sweeps[i].len:
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# let a = sweeps[i][aIndex]
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# # echo i, ":", sweeps.len, ":", cutLines.len
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# let aSeg = segment(vec2(a.atx, cutLines[i]), vec2(a.tox, cutLines[i+1]))
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# for bIndex in aIndex + 1 ..< sweeps[i].len:
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# let b = sweeps[i][bIndex]
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# let bSeg = segment(vec2(b.atx, cutLines[i]), vec2(b.tox, cutLines[i+1]))
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# var at: Vec2
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# if intersectsInner(aSeg, bSeg, at):
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# crossCuts.binaryInsert(at.y)
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# if crossCuts.len > 0:
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# var
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# thisSweep = sweeps[i]
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# yTop = cutLines[i]
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# yBottom = cutLines[i + 1]
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# sweeps[i].setLen(0)
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# for k in crossCuts:
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# let prevLen = cutLines.len
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# cutLines.binaryInsert(k)
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# if prevLen != cutLines.len:
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# sweeps.insert(newSeq[SweepLine](), i + 1)
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# for a in thisSweep:
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# var seg = segment(vec2(a.atx, yTop), vec2(a.tox, yBottom))
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# var at: Vec2
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# for j, cutterLine in crossCuts:
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# if intersects(line(vec2(0, cutterLine), vec2(1, cutterLine)), seg, at):
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# sweeps[i+j].add(toLine((segment(seg.at, at), a.winding)))
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# seg = segment(at, seg.to)
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# sweeps[i+crossCuts.len].add(toLine((seg, a.winding)))
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# i += crossCuts.len
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# inc i
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i = 0
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while i < sweeps.len:
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# Sort the sweep by X
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sweeps[i].sortSweepLines(0, sweeps[i].high)
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# Do winding order
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var
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pen = 0
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prevFill = false
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j = 0
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while j < sweeps[i].len:
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let a = sweeps[i][j]
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if a.winding == 1:
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inc pen
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if a.winding == -1:
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dec pen
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let thisFill = shouldFill(windingRule, pen)
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if prevFill == thisFill:
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# Remove this sweep line.
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sweeps[i].delete(j)
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continue
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prevFill = thisFill
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inc j
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inc i
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# Used to debug sweeps:
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# for s in 0 ..< sweeps.len:
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# let
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# y1 = cutLines[s]
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# echo "M -100 ", y1
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# echo "L 300 ", y1
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# for line in sweeps[s]:
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# let
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# nw = vec2(line.atx, cutLines[s])
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# sw = vec2(line.tox, cutLines[s + 1])
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# echo "M ", nw.x, " ", nw.y
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# echo "L ", sw.x, " ", sw.y
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proc computeCoverage(
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coverages: var seq[uint16],
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y: int,
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startX: int,
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cutLines: seq[float32],
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currCutLine: int,
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sweep: seq[SweepLine]
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) =
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if cutLines[currCutLine + 1] - cutLines[currCutLine] < 1/256:
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# TODO some thing about micro sweeps
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return
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let
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sweepHeight = cutLines[currCutLine + 1] - cutLines[currCutLine]
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yFracTop = ((y.float32 - cutLines[currCutLine]) / sweepHeight).clamp(0, 1)
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yFracBottom = ((y.float32 + 1 - cutLines[currCutLine]) /
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sweepHeight).clamp(0, 1)
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var i = 0
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while i < sweep.len:
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let
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nwX = mix(sweep[i+0].atx, sweep[i+0].tox, yFracTop)
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neX = mix(sweep[i+1].atx, sweep[i+1].tox, yFracTop)
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swX = mix(sweep[i+0].atx, sweep[i+0].tox, yFracBottom)
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seX = mix(sweep[i+1].atx, sweep[i+1].tox, yFracBottom)
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minWi = min(nwX, swX).int #.clamp(startX, coverages.len + startX)
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maxWi = max(nwX, swX).ceil.int #.clamp(startX, coverages.len + startX)
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minEi = min(neX, seX).int #.clamp(startX, coverages.len + startX)
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maxEi = max(neX, seX).ceil.int #.clamp(startX, coverages.len + startX)
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let
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nw = vec2(sweep[i+0].atx, cutLines[currCutLine])
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sw = vec2(sweep[i+0].tox, cutLines[currCutLine + 1])
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f16 = (256 * 256 - 1).float32
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for x in minWi ..< maxWi:
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var area = pixelCover(
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nw - vec2(x.float32, y.float32),
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sw - vec2(x.float32, y.float32)
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)
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coverages[x - startX] += (area * f16).uint16
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let x = maxWi
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var midArea = pixelCover(
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nw - vec2(x.float32, y.float32),
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sw - vec2(x.float32, y.float32)
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)
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for x in maxWi ..< maxEi:
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coverages[x - startX] += (midArea * f16).uint16
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let
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ne = vec2(sweep[i+1].atx, cutLines[currCutLine])
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se = vec2(sweep[i+1].tox, cutLines[currCutLine + 1])
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for x in minEi ..< maxEi:
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var area = pixelCover(
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ne - vec2(x.float32, y.float32),
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se - vec2(x.float32, y.float32)
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)
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coverages[x - startX] -= (area * f16).uint16
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i += 2
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var
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currCutLine = 0
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coverages16 = newSeq[uint16](bounds.w.int)
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coverages8 = newSeq[uint8](bounds.w.int)
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for scanLine in max(cutLines[0].int, 0) ..< min(cutLines[^1].ceil.int, image.height):
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zeroMem(coverages16[0].addr, coverages16.len * 2)
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coverages16.computeCoverage(
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scanLine, startX, cutLines, currCutLine, sweeps[currCutLine])
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while cutLines[currCutLine + 1] < scanLine.float + 1.0:
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inc currCutLine
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if currCutLine == sweeps.len:
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break
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coverages16.computeCoverage(
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scanLine, startX, cutLines, currCutLine, sweeps[currCutLine])
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for i in 0 ..< coverages16.len:
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coverages8[i] = (coverages16[i] shr 8).uint8
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image.fillCoverage(
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rgbx,
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startX = startX,
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y = scanLine,
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coverages8,
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blendMode
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)
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else:
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@ -1580,7 +1580,59 @@ proc fillShapes(
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color: SomeColor,
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windingRule: WindingRule,
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blendMode: BlendMode
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)
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) =
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# Figure out the total bounds of all the shapes,
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# rasterize only within the total bounds
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let
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rgbx = color.asRgbx()
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segments = shapes.shapesToSegments()
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bounds = computeBounds(segments).snapToPixels()
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startX = max(0, bounds.x.int)
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startY = max(0, bounds.y.int)
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pathHeight = min(image.height, (bounds.y + bounds.h).int)
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partitioning = partitionSegments(segments, startY, pathHeight - startY)
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var
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coverages = newSeq[uint8](bounds.w.int)
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hits = newSeq[(float32, int16)](partitioning.maxEntryCount)
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numHits: int
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aa: bool
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for y in startY ..< pathHeight:
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computeCoverage(
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cast[ptr UncheckedArray[uint8]](coverages[0].addr),
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||||
hits,
|
||||
numHits,
|
||||
aa,
|
||||
image.width.float32,
|
||||
y,
|
||||
startX,
|
||||
partitioning,
|
||||
windingRule
|
||||
)
|
||||
if aa:
|
||||
image.fillCoverage(
|
||||
rgbx,
|
||||
startX,
|
||||
y,
|
||||
coverages,
|
||||
blendMode
|
||||
)
|
||||
zeroMem(coverages[0].addr, coverages.len)
|
||||
else:
|
||||
image.fillHits(
|
||||
rgbx,
|
||||
startX,
|
||||
y,
|
||||
hits,
|
||||
numHits,
|
||||
windingRule,
|
||||
blendMode
|
||||
)
|
||||
|
||||
if blendMode == bmMask:
|
||||
image.clearUnsafe(0, 0, 0, startY)
|
||||
image.clearUnsafe(0, pathHeight, 0, image.height)
|
||||
|
||||
proc fillShapes(
|
||||
mask: Mask,
|
||||
|
|
@ -2017,491 +2069,6 @@ proc strokeOverlaps*(
|
|||
strokeShapes.transform(transform)
|
||||
strokeShapes.overlaps(test, wrNonZero)
|
||||
|
||||
when defined(pixieSweeps):
|
||||
import algorithm
|
||||
|
||||
proc pixelCover(a0, b0: Vec2): float32 =
|
||||
## Returns the amount of area a given segment sweeps to the right
|
||||
## in a [0,0 to 1,1] box.
|
||||
var
|
||||
a = a0
|
||||
b = b0
|
||||
aI: Vec2
|
||||
bI: Vec2
|
||||
area: float32 = 0.0
|
||||
|
||||
if (a.x < 0 and b.x < 0) or # Both to the left.
|
||||
(a.x == b.x): # Vertical line
|
||||
# Area of the rectangle:
|
||||
return (1 - clamp(a.x, 0, 1)) * (min(b.y, 1) - max(a.y, 0))
|
||||
|
||||
else:
|
||||
# y = mm*x + bb
|
||||
let
|
||||
mm: float32 = (b.y - a.y) / (b.x - a.x)
|
||||
bb: float32 = a.y - mm * a.x
|
||||
|
||||
if a.x >= 0 and a.x <= 1 and a.y >= 0 and a.y <= 1:
|
||||
# A is in pixel bounds.
|
||||
aI = a
|
||||
else:
|
||||
aI = vec2((0 - bb) / mm, 0)
|
||||
if aI.x < 0:
|
||||
let y = mm * 0 + bb
|
||||
# Area of the extra rectangle.
|
||||
area += (min(bb, 1) - max(a.y, 0)).clamp(0, 1)
|
||||
aI = vec2(0, y.clamp(0, 1))
|
||||
elif aI.x > 1:
|
||||
let y = mm * 1 + bb
|
||||
aI = vec2(1, y.clamp(0, 1))
|
||||
|
||||
if b.x >= 0 and b.x <= 1 and b.y >= 0 and b.y <= 1:
|
||||
# B is in pixel bounds.
|
||||
bI = b
|
||||
else:
|
||||
bI = vec2((1 - bb) / mm, 1)
|
||||
if bI.x < 0:
|
||||
let y = mm * 0 + bb
|
||||
# Area of the extra rectangle.
|
||||
area += (min(b.y, 1) - max(bb, 0)).clamp(0, 1)
|
||||
bI = vec2(0, y.clamp(0, 1))
|
||||
elif bI.x > 1:
|
||||
let y = mm * 1 + bb
|
||||
bI = vec2(1, y.clamp(0, 1))
|
||||
|
||||
area += ((1 - aI.x) + (1 - bI.x)) / 2 * (bI.y - aI.y)
|
||||
return area
|
||||
|
||||
proc intersectsInner*(a, b: Segment, at: var Vec2): bool {.inline.} =
|
||||
## Checks if the a segment intersects b segment.
|
||||
## If it returns true, at will have point of intersection
|
||||
let
|
||||
s1 = a.to - a.at
|
||||
s2 = b.to - b.at
|
||||
denominator = (-s2.x * s1.y + s1.x * s2.y)
|
||||
s = (-s1.y * (a.at.x - b.at.x) + s1.x * (a.at.y - b.at.y)) / denominator
|
||||
t = (s2.x * (a.at.y - b.at.y) - s2.y * (a.at.x - b.at.x)) / denominator
|
||||
|
||||
if s > 0 and s < 1 and t > 0 and t < 1:
|
||||
at = a.at + (t * s1)
|
||||
return true
|
||||
|
||||
type
|
||||
|
||||
Trapezoid = object
|
||||
nw, ne, se, sw: Vec2
|
||||
|
||||
SweepLine = object
|
||||
#m, x, b: float32
|
||||
atx, tox: float32
|
||||
winding: int16
|
||||
|
||||
proc toLine(s: (Segment, int16)): SweepLine =
|
||||
var line = SweepLine()
|
||||
line.atx = s[0].at.x
|
||||
line.tox = s[0].to.x
|
||||
# y = mx + b
|
||||
# line.m = (s.at.y - s.to.y) / (s.at.x - s.to.x)
|
||||
# line.b = s.at.y - line.m * s.at.x
|
||||
line.winding = s[1]
|
||||
return line
|
||||
|
||||
proc intersectsYLine(
|
||||
y: float32, s: Segment, atx: var float32
|
||||
): bool {.inline.} =
|
||||
let
|
||||
s2y = s.to.y - s.at.y
|
||||
denominator = -s2y
|
||||
numerator = s.at.y - y
|
||||
u = numerator / denominator
|
||||
if u >= 0 and u <= 1:
|
||||
let at = s.at + (u * vec2(s.to.x - s.at.x, s2y))
|
||||
atx = at.x
|
||||
return true
|
||||
|
||||
proc binaryInsert(arr: var seq[float32], v: float32) =
|
||||
if arr.len == 0:
|
||||
arr.add(v)
|
||||
return
|
||||
var
|
||||
L = 0
|
||||
R = arr.len - 1
|
||||
while L < R:
|
||||
let m = (L + R) div 2
|
||||
if arr[m] ~= v:
|
||||
return
|
||||
elif arr[m] < v:
|
||||
L = m + 1
|
||||
else: # arr[m] > v:
|
||||
R = m - 1
|
||||
if arr[L] ~= v:
|
||||
return
|
||||
elif arr[L] > v:
|
||||
arr.insert(v, L)
|
||||
else:
|
||||
arr.insert(v, L + 1)
|
||||
|
||||
proc sortSegments(segments: var seq[(Segment, int16)], inl, inr: int) =
|
||||
## Quicksort + insertion sort, in-place and faster than standard lib sort.
|
||||
|
||||
let n = inr - inl + 1
|
||||
if n < 32: # Use insertion sort for the rest
|
||||
for i in inl + 1 .. inr:
|
||||
var
|
||||
j = i - 1
|
||||
k = i
|
||||
while j >= 0 and segments[j][0].at.y > segments[k][0].at.y:
|
||||
swap(segments[j + 1], segments[j])
|
||||
dec j
|
||||
dec k
|
||||
return
|
||||
var
|
||||
l = inl
|
||||
r = inr
|
||||
let p = segments[l + n div 2][0].at.y
|
||||
while l <= r:
|
||||
if segments[l][0].at.y < p:
|
||||
inc l
|
||||
elif segments[r][0].at.y > p:
|
||||
dec r
|
||||
else:
|
||||
swap(segments[l], segments[r])
|
||||
inc l
|
||||
dec r
|
||||
sortSegments(segments, inl, r)
|
||||
sortSegments(segments, l, inr)
|
||||
|
||||
proc sortSweepLines(segments: var seq[SweepLine], inl, inr: int) =
|
||||
## Quicksort + insertion sort, in-place and faster than standard lib sort.
|
||||
|
||||
proc avg(line: SweepLine): float32 {.inline.} =
|
||||
(line.tox + line.atx) / 2.float32
|
||||
|
||||
let n = inr - inl + 1
|
||||
if n < 32: # Use insertion sort for the rest
|
||||
for i in inl + 1 .. inr:
|
||||
var
|
||||
j = i - 1
|
||||
k = i
|
||||
while j >= 0 and segments[j].avg > segments[k].avg:
|
||||
swap(segments[j + 1], segments[j])
|
||||
dec j
|
||||
dec k
|
||||
return
|
||||
var
|
||||
l = inl
|
||||
r = inr
|
||||
let p = segments[l + n div 2].avg
|
||||
while l <= r:
|
||||
if segments[l].avg < p:
|
||||
inc l
|
||||
elif segments[r].avg > p:
|
||||
dec r
|
||||
else:
|
||||
swap(segments[l], segments[r])
|
||||
inc l
|
||||
dec r
|
||||
sortSweepLines(segments, inl, r)
|
||||
sortSweepLines(segments, l, inr)
|
||||
|
||||
proc fillShapes(
|
||||
image: Image,
|
||||
shapes: seq[seq[Vec2]],
|
||||
color: SomeColor,
|
||||
windingRule: WindingRule,
|
||||
blendMode: BlendMode
|
||||
) =
|
||||
|
||||
let rgbx = color.rgbx
|
||||
var segments = shapes.shapesToSegments()
|
||||
let
|
||||
bounds = computeBounds(segments).snapToPixels()
|
||||
startX = max(0, bounds.x.int)
|
||||
|
||||
if segments.len == 0 or bounds.w.int == 0 or bounds.h.int == 0:
|
||||
return
|
||||
|
||||
# const q = 1/10
|
||||
# for i in 0 ..< segments.len:
|
||||
# segments[i][0].at.x = quantize(segments[i][0].at.x, q)
|
||||
# segments[i][0].at.y = quantize(segments[i][0].at.y, q)
|
||||
# segments[i][0].to.x = quantize(segments[i][0].to.x, q)
|
||||
# segments[i][0].to.y = quantize(segments[i][0].to.y, q)
|
||||
|
||||
# Create sorted segments.
|
||||
segments.sortSegments(0, segments.high)
|
||||
|
||||
# Compute cut lines
|
||||
var cutLines: seq[float32]
|
||||
for s in segments:
|
||||
cutLines.binaryInsert(s[0].at.y)
|
||||
cutLines.binaryInsert(s[0].to.y)
|
||||
|
||||
var
|
||||
# Dont add bottom cutLine.
|
||||
sweeps = newSeq[seq[SweepLine]](cutLines.len - 1)
|
||||
lastSeg = 0
|
||||
i = 0
|
||||
while i < sweeps.len:
|
||||
|
||||
if lastSeg < segments.len:
|
||||
|
||||
while segments[lastSeg][0].at.y == cutLines[i]:
|
||||
let s = segments[lastSeg]
|
||||
|
||||
if s[0].to.y != cutLines[i + 1]:
|
||||
var atx: float32
|
||||
var seg = s[0]
|
||||
for j in i ..< sweeps.len:
|
||||
let y = cutLines[j + 1]
|
||||
if intersectsYLine(y, seg, atx):
|
||||
sweeps[j].add(toLine((segment(seg.at, vec2(atx, y)), s[1])))
|
||||
seg = segment(vec2(atx, y), seg.to)
|
||||
else:
|
||||
if seg.at.y != seg.to.y:
|
||||
sweeps[j].add(toLine(s))
|
||||
break
|
||||
else:
|
||||
sweeps[i].add(toLine(s))
|
||||
|
||||
inc lastSeg
|
||||
if lastSeg >= segments.len:
|
||||
break
|
||||
inc i
|
||||
|
||||
# i = 0
|
||||
# while i < sweeps.len:
|
||||
# # TODO: Maybe finds all cuts first, add them to array, cut all lines at once.
|
||||
# var crossCuts: seq[float32]
|
||||
|
||||
# # echo i, " cut?"
|
||||
|
||||
# for aIndex in 0 ..< sweeps[i].len:
|
||||
# let a = sweeps[i][aIndex]
|
||||
# # echo i, ":", sweeps.len, ":", cutLines.len
|
||||
# let aSeg = segment(vec2(a.atx, cutLines[i]), vec2(a.tox, cutLines[i+1]))
|
||||
# for bIndex in aIndex + 1 ..< sweeps[i].len:
|
||||
# let b = sweeps[i][bIndex]
|
||||
# let bSeg = segment(vec2(b.atx, cutLines[i]), vec2(b.tox, cutLines[i+1]))
|
||||
# var at: Vec2
|
||||
# if intersectsInner(aSeg, bSeg, at):
|
||||
# crossCuts.binaryInsert(at.y)
|
||||
|
||||
# if crossCuts.len > 0:
|
||||
# var
|
||||
# thisSweep = sweeps[i]
|
||||
# yTop = cutLines[i]
|
||||
# yBottom = cutLines[i + 1]
|
||||
# sweeps[i].setLen(0)
|
||||
|
||||
# for k in crossCuts:
|
||||
# let prevLen = cutLines.len
|
||||
# cutLines.binaryInsert(k)
|
||||
# if prevLen != cutLines.len:
|
||||
# sweeps.insert(newSeq[SweepLine](), i + 1)
|
||||
|
||||
# for a in thisSweep:
|
||||
# var seg = segment(vec2(a.atx, yTop), vec2(a.tox, yBottom))
|
||||
# var at: Vec2
|
||||
# for j, cutterLine in crossCuts:
|
||||
# if intersects(line(vec2(0, cutterLine), vec2(1, cutterLine)), seg, at):
|
||||
# sweeps[i+j].add(toLine((segment(seg.at, at), a.winding)))
|
||||
# seg = segment(at, seg.to)
|
||||
# sweeps[i+crossCuts.len].add(toLine((seg, a.winding)))
|
||||
|
||||
# i += crossCuts.len
|
||||
|
||||
# inc i
|
||||
|
||||
i = 0
|
||||
while i < sweeps.len:
|
||||
# Sort the sweep by X
|
||||
sweeps[i].sortSweepLines(0, sweeps[i].high)
|
||||
# Do winding order
|
||||
var
|
||||
pen = 0
|
||||
prevFill = false
|
||||
j = 0
|
||||
while j < sweeps[i].len:
|
||||
let a = sweeps[i][j]
|
||||
if a.winding == 1:
|
||||
inc pen
|
||||
if a.winding == -1:
|
||||
dec pen
|
||||
let thisFill = shouldFill(windingRule, pen)
|
||||
if prevFill == thisFill:
|
||||
# Remove this sweep line.
|
||||
sweeps[i].delete(j)
|
||||
continue
|
||||
prevFill = thisFill
|
||||
inc j
|
||||
inc i
|
||||
|
||||
# Used to debug sweeps:
|
||||
# for s in 0 ..< sweeps.len:
|
||||
# let
|
||||
# y1 = cutLines[s]
|
||||
# echo "M -100 ", y1
|
||||
# echo "L 300 ", y1
|
||||
# for line in sweeps[s]:
|
||||
# let
|
||||
# nw = vec2(line.atx, cutLines[s])
|
||||
# sw = vec2(line.tox, cutLines[s + 1])
|
||||
# echo "M ", nw.x, " ", nw.y
|
||||
# echo "L ", sw.x, " ", sw.y
|
||||
|
||||
proc computeCoverage(
|
||||
coverages: var seq[uint16],
|
||||
y: int,
|
||||
startX: int,
|
||||
cutLines: seq[float32],
|
||||
currCutLine: int,
|
||||
sweep: seq[SweepLine]
|
||||
) =
|
||||
|
||||
if cutLines[currCutLine + 1] - cutLines[currCutLine] < 1/256:
|
||||
# TODO some thing about micro sweeps
|
||||
return
|
||||
|
||||
let
|
||||
sweepHeight = cutLines[currCutLine + 1] - cutLines[currCutLine]
|
||||
yFracTop = ((y.float32 - cutLines[currCutLine]) / sweepHeight).clamp(0, 1)
|
||||
yFracBottom = ((y.float32 + 1 - cutLines[currCutLine]) /
|
||||
sweepHeight).clamp(0, 1)
|
||||
var i = 0
|
||||
while i < sweep.len:
|
||||
let
|
||||
nwX = mix(sweep[i+0].atx, sweep[i+0].tox, yFracTop)
|
||||
neX = mix(sweep[i+1].atx, sweep[i+1].tox, yFracTop)
|
||||
|
||||
swX = mix(sweep[i+0].atx, sweep[i+0].tox, yFracBottom)
|
||||
seX = mix(sweep[i+1].atx, sweep[i+1].tox, yFracBottom)
|
||||
|
||||
minWi = min(nwX, swX).int #.clamp(startX, coverages.len + startX)
|
||||
maxWi = max(nwX, swX).ceil.int #.clamp(startX, coverages.len + startX)
|
||||
|
||||
minEi = min(neX, seX).int #.clamp(startX, coverages.len + startX)
|
||||
maxEi = max(neX, seX).ceil.int #.clamp(startX, coverages.len + startX)
|
||||
|
||||
let
|
||||
nw = vec2(sweep[i+0].atx, cutLines[currCutLine])
|
||||
sw = vec2(sweep[i+0].tox, cutLines[currCutLine + 1])
|
||||
f16 = (256 * 256 - 1).float32
|
||||
for x in minWi ..< maxWi:
|
||||
var area = pixelCover(
|
||||
nw - vec2(x.float32, y.float32),
|
||||
sw - vec2(x.float32, y.float32)
|
||||
)
|
||||
coverages[x - startX] += (area * f16).uint16
|
||||
|
||||
let x = maxWi
|
||||
var midArea = pixelCover(
|
||||
nw - vec2(x.float32, y.float32),
|
||||
sw - vec2(x.float32, y.float32)
|
||||
)
|
||||
for x in maxWi ..< maxEi:
|
||||
coverages[x - startX] += (midArea * f16).uint16
|
||||
|
||||
let
|
||||
ne = vec2(sweep[i+1].atx, cutLines[currCutLine])
|
||||
se = vec2(sweep[i+1].tox, cutLines[currCutLine + 1])
|
||||
for x in minEi ..< maxEi:
|
||||
var area = pixelCover(
|
||||
ne - vec2(x.float32, y.float32),
|
||||
se - vec2(x.float32, y.float32)
|
||||
)
|
||||
coverages[x - startX] -= (area * f16).uint16
|
||||
|
||||
i += 2
|
||||
|
||||
var
|
||||
currCutLine = 0
|
||||
coverages16 = newSeq[uint16](bounds.w.int)
|
||||
coverages8 = newSeq[uint8](bounds.w.int)
|
||||
for scanLine in max(cutLines[0].int, 0) ..< min(cutLines[^1].ceil.int, image.height):
|
||||
|
||||
zeroMem(coverages16[0].addr, coverages16.len * 2)
|
||||
|
||||
coverages16.computeCoverage(
|
||||
scanLine, startX, cutLines, currCutLine, sweeps[currCutLine])
|
||||
while cutLines[currCutLine + 1] < scanLine.float + 1.0:
|
||||
inc currCutLine
|
||||
if currCutLine == sweeps.len:
|
||||
break
|
||||
coverages16.computeCoverage(
|
||||
scanLine, startX, cutLines, currCutLine, sweeps[currCutLine])
|
||||
|
||||
for i in 0 ..< coverages16.len:
|
||||
coverages8[i] = (coverages16[i] shr 8).uint8
|
||||
image.fillCoverage(
|
||||
rgbx,
|
||||
startX = startX,
|
||||
y = scanLine,
|
||||
coverages8,
|
||||
blendMode
|
||||
)
|
||||
|
||||
else:
|
||||
proc fillShapes(
|
||||
image: Image,
|
||||
shapes: seq[seq[Vec2]],
|
||||
color: SomeColor,
|
||||
windingRule: WindingRule,
|
||||
blendMode: BlendMode
|
||||
) =
|
||||
# Figure out the total bounds of all the shapes,
|
||||
# rasterize only within the total bounds
|
||||
let
|
||||
rgbx = color.asRgbx()
|
||||
segments = shapes.shapesToSegments()
|
||||
bounds = computeBounds(segments).snapToPixels()
|
||||
startX = max(0, bounds.x.int)
|
||||
startY = max(0, bounds.y.int)
|
||||
pathHeight = min(image.height, (bounds.y + bounds.h).int)
|
||||
partitioning = partitionSegments(segments, startY, pathHeight - startY)
|
||||
|
||||
var
|
||||
coverages = newSeq[uint8](bounds.w.int)
|
||||
hits = newSeq[(float32, int16)](partitioning.maxEntryCount)
|
||||
numHits: int
|
||||
aa: bool
|
||||
|
||||
for y in startY ..< pathHeight:
|
||||
computeCoverage(
|
||||
cast[ptr UncheckedArray[uint8]](coverages[0].addr),
|
||||
hits,
|
||||
numHits,
|
||||
aa,
|
||||
image.width.float32,
|
||||
y,
|
||||
startX,
|
||||
partitioning,
|
||||
windingRule
|
||||
)
|
||||
if aa:
|
||||
image.fillCoverage(
|
||||
rgbx,
|
||||
startX,
|
||||
y,
|
||||
coverages,
|
||||
blendMode
|
||||
)
|
||||
zeroMem(coverages[0].addr, coverages.len)
|
||||
else:
|
||||
image.fillHits(
|
||||
rgbx,
|
||||
startX,
|
||||
y,
|
||||
hits,
|
||||
numHits,
|
||||
windingRule,
|
||||
blendMode
|
||||
)
|
||||
|
||||
if blendMode == bmMask:
|
||||
image.clearUnsafe(0, 0, 0, startY)
|
||||
image.clearUnsafe(0, pathHeight, 0, image.height)
|
||||
|
||||
proc fillMask(
|
||||
shapes: seq[seq[Vec2]], width, height: int, windingRule = wrNonZero
|
||||
): Mask =
|
||||
|
|
|
|||
Loading…
Reference in a new issue