Merge pull request #326 from guzba/master

fix cairo svg, add svg upscale test, stroke optimization

experiments/benchmark_cairo.nim

@@ -1,96 +1,141 @@
-import benchy, cairo, chroma, math, pixie
+import benchy, cairo, chroma, math, pixie, pixie/paths {.all.}, strformat
+
+proc doDiff(a, b: Image, name: string) =
+  let (diffScore, diffImage) = diff(a, b)
+  echo &"{name} score: {diffScore}"
+  diffImage.writeFile(&"{name}_diff.png")
 
 block:
+  let path = newPath()
+  path.moveTo(0, 0)
+  path.lineTo(1920, 0)
+  path.lineTo(1920, 1080)
+  path.lineTo(0, 1080)
+  path.closePath()
+
+  let shapes = path.commandsToShapes(true, 1)
+
   let
     surface = imageSurfaceCreate(FORMAT_ARGB32, 1920, 1080)
     ctx = surface.create()
-
   ctx.setSourceRgba(0, 0, 1, 1)
 
   timeIt "cairo1":
     ctx.newPath()
-    ctx.moveTo(0, 0)
-    ctx.lineTo(1920, 0)
-    ctx.lineTo(1920, 1080)
-    ctx.lineTo(0, 1080)
-    ctx.closePath()
+    ctx.moveTo(shapes[0][0].x, shapes[0][0].y)
+    for shape in shapes:
+      for v in shape:
+        ctx.lineTo(v.x, v.y)
     ctx.fill()
     surface.flush()
 
   # discard surface.writeToPng("cairo1.png")
 
   let a = newImage(1920, 1080)
-  a.fill(rgba(255, 255, 255, 255))
 
   timeIt "pixie1":
     let p = newPath()
-    p.moveTo(0, 0)
-    p.lineTo(1920, 0)
-    p.lineTo(1920, 1080)
-    p.lineTo(0, 1080)
-    p.closePath()
+    p.moveTo(shapes[0][0])
+    for shape in shapes:
+      for v in shape:
+        p.lineTo(v)
     a.fillPath(p, rgba(0, 0, 255, 255))
 
   # a.writeFile("pixie1.png")
 
 block:
+  let path = newPath()
+  path.moveTo(500, 240)
+  path.lineTo(1500, 240)
+  path.lineTo(1920, 600)
+  path.lineTo(0, 600)
+  path.closePath()
+
+  let shapes = path.commandsToShapes(true, 1)
+
   let
     surface = imageSurfaceCreate(FORMAT_ARGB32, 1920, 1080)
     ctx = surface.create()
 
-  ctx.setSourceRgba(0, 0, 1, 1)
-
   timeIt "cairo2":
+    ctx.setSourceRgba(1, 1, 1, 1)
+    let operator = ctx.getOperator()
+    ctx.setOperator(OperatorSource)
+    ctx.paint()
+    ctx.setOperator(operator)
+
+    ctx.setSourceRgba(0, 0, 1, 1)
+
     ctx.newPath()
-    ctx.moveTo(500, 240)
-    ctx.lineTo(1500, 240)
-    ctx.lineTo(1920, 600)
-    ctx.lineTo(0, 600)
-    ctx.closePath()
+    ctx.moveTo(shapes[0][0].x, shapes[0][0].y)
+    for shape in shapes:
+      for v in shape:
+        ctx.lineTo(v.x, v.y)
     ctx.fill()
-  surface.flush()
+    surface.flush()
 
   # discard surface.writeToPng("cairo2.png")
 
   let a = newImage(1920, 1080)
-  a.fill(rgba(255, 255, 255, 255))
 
   timeIt "pixie2":
+    a.fill(rgba(255, 255, 255, 255))
+
     let p = newPath()
-    p.moveTo(500, 240)
-    p.lineTo(1500, 240)
-    p.lineTo(1920, 600)
-    p.lineTo(0, 600)
-    p.closePath()
+    p.moveTo(shapes[0][0])
+    for shape in shapes:
+      for v in shape:
+        p.lineTo(v)
     a.fillPath(p, rgba(0, 0, 255, 255))
 
   # a.writeFile("pixie2.png")
 
-# block:
-#   let
-#     a = imageSurfaceCreate(FORMAT_ARGB32, 1000, 1000)
-#     b = imageSurfaceCreate(FORMAT_ARGB32, 500, 500)
-#     ac = a.create()
-#     bc = b.create()
+block:
+  let path = parsePath("""
+      M 100,300
+      A 200,200 0,0,1 500,300
+      A 200,200 0,0,1 900,300
+      Q 900,600 500,900
+      Q 100,600 100,300 z
+  """)
 
-#   ac.setSourceRgba(1, 0, 0, 1)
-#   ac.newPath()
-#   ac.rectangle(0, 0, 1000, 1000)
-#   ac.fill()
+  let shapes = path.commandsToShapes(true, 1)
 
-#   bc.setSourceRgba(0, 1, 0, 1)
-#   bc.newPath()
-#   bc.rectangle(0, 0, 500, 500)
-#   bc.fill()
+  let
+    surface = imageSurfaceCreate(FORMAT_ARGB32, 1000, 1000)
+    ctx = surface.create()
 
-#   let pattern = patternCreateForSurface(b)
+  timeIt "cairo3":
+    ctx.setSourceRgba(1, 1, 1, 1)
+    let operator = ctx.getOperator()
+    ctx.setOperator(OperatorSource)
+    ctx.paint()
+    ctx.setOperator(operator)
 
-#   timeIt "a":
-#     ac.setSource(pattern)
-#     ac.save()
-#     ac.translate(25.2, 25.2)
-#     ac.rectangle(0, 0, 500, 500)
-#     ac.fill()
-#     ac.restore()
+    ctx.setSourceRgba(1, 0, 0, 1)
 
-#   discard a.writeToPng("a.png")
+    ctx.newPath()
+    ctx.moveTo(shapes[0][0].x, shapes[0][0].y)
+    for shape in shapes:
+      for v in shape:
+        ctx.lineTo(v.x, v.y)
+    ctx.fill()
+    surface.flush()
+
+  # discard surface.writeToPng("cairo3.png")
+
+  let a = newImage(1000, 1000)
+
+  timeIt "pixie3":
+    a.fill(rgba(255, 255, 255, 255))
+
+    let p = newPath()
+    p.moveTo(shapes[0][0])
+    for shape in shapes:
+      for v in shape:
+        p.lineTo(v)
+    a.fillPath(p, rgba(255, 0, 0, 255))
+
+  # a.writeFile("pixie3.png")
+
+  # doDiff(readImage("cairo3.png"), a, "cairo3")

experiments/svg_cairo.nim

@@ -1,20 +1,28 @@
 ## Load and Save SVG files.
 
-import cairo, chroma, pixie/common, pixie/images, strutils, vmath, xmlparser, xmltree
+import cairo, chroma, pixie/common, pixie/images, pixie/paints, strutils, tables,
+    vmath, xmlparser, xmltree
 
 include pixie/paths
 
-# type Path = paths.Path
-
 proc processCommands(c: ptr Context, path: Path) =
   c.newPath()
   c.moveTo(0, 0)
-  for i, command in path.commands:
+
+  var
+    prevCommandKind = Move
+    start, at, prevCtrl2: Vec2
+  for command in path.commands:
     case command.kind
     of Move:
       c.moveTo(command.numbers[0], command.numbers[1])
+      at.x = command.numbers[0]
+      at.y = command.numbers[1]
+      start = at
     of Line:
       c.lineTo(command.numbers[0], command.numbers[1])
+      at.x = command.numbers[0]
+      at.y = command.numbers[1]
     of HLine:
       echo "HLine not yet supported for Cairo"
     of VLine:
@@ -28,6 +36,9 @@ proc processCommands(c: ptr Context, path: Path) =
         command.numbers[4],
         command.numbers[5]
       )
+      at.x = command.numbers[4]
+      at.y = command.numbers[5]
+      prevCtrl2 = vec2(command.numbers[2], command.numbers[3])
     of SCubic:
       echo "SCubic not yet supported for Cairo"
     of Quad:
@@ -38,12 +49,19 @@ proc processCommands(c: ptr Context, path: Path) =
       echo "Arc not yet supported for Cairo"
     of RMove:
       c.relMoveTo(command.numbers[0], command.numbers[1])
+      at.x += command.numbers[0]
+      at.y += command.numbers[1]
+      start = at
     of RLine:
       c.relLineTo(command.numbers[0], command.numbers[1])
+      at.x += command.numbers[0]
+      at.y += command.numbers[1]
     of RHLine:
       c.relLineTo(command.numbers[0], 0)
+      at.x += command.numbers[0]
     of RVLine:
       c.relLineTo(0, command.numbers[0])
+      at.y += command.numbers[0]
     of RCubic:
       c.relCurveTo(
         command.numbers[0],
@@ -53,12 +71,28 @@ proc processCommands(c: ptr Context, path: Path) =
         command.numbers[4],
         command.numbers[5]
       )
+      prevCtrl2 = vec2(at.x + command.numbers[2], at.y + command.numbers[3])
+      at.x += command.numbers[4]
+      at.y += command.numbers[5]
     of RSCubic:
-      # This is not correct but good enough for now
-      c.relLineTo(
-        command.numbers[2],
-        command.numbers[3]
+      let
+        ctrl1 =
+          if prevCommandKind in {Cubic, SCubic, RCubic, RSCubic}:
+            at * 2 - prevCtrl2
+          else:
+            at
+        ctrl2 = vec2(at.x + command.numbers[0], at.y + command.numbers[1])
+        to = vec2(at.x + command.numbers[2], at.y + command.numbers[3])
+      c.curveTo(
+        ctrl1.x,
+        ctrl1.y,
+        ctrl2.x,
+        ctrl2.y,
+        to.x,
+        to.y
       )
+      prevCtrl2 = ctrl2
+      at = to
     of RQuad:
       echo "RQuad not supported by Cairo"
     of RTQuad:
@@ -67,18 +101,21 @@ proc processCommands(c: ptr Context, path: Path) =
       echo "RArc not yet supported for Cairo"
     of Close:
       c.closePath()
+      at = start
+
+    prevCommandKind = command.kind
 
     checkStatus(c.status())
 
 proc prepare(
   c: ptr Context,
   path: Path,
-  color: ColorRGBA,
+  paint: Paint,
   mat: Mat3,
   windingRule = wrNonZero
 ) =
   let
-    color = color.color()
+    color = paint.color
     matrix = Matrix(
       xx: mat[0, 0],
       yx: mat[0, 1],
@@ -96,16 +133,25 @@ proc prepare(
     c.setFillRule(FillRuleEvenOdd)
   c.processCommands(path)
 
-type Ctx = object
-  fillRule: WindingRule
-  fill, stroke: ColorRGBA
-  strokeWidth: float32
-  strokeLineCap: LineCap
-  strokeLineJoin: LineJoin
-  strokeMiterLimit: float32
-  strokeDashArray: seq[float32]
-  transform: Mat3
-  shouldStroke: bool
+type
+  LinearGradient = object
+    x1, y1, x2, y2: float32
+    stops: seq[ColorStop]
+
+  Ctx = object
+    display: bool
+    fillRule: WindingRule
+    fill: Paint
+    stroke: ColorRGBX
+    strokeWidth: float32
+    strokeLineCap: LineCap
+    strokeLineJoin: LineJoin
+    strokeMiterLimit: float32
+    strokeDashArray: seq[float32]
+    transform: Mat3
+    shouldStroke: bool
+    opacity, strokeOpacity: float32
+    linearGradients: TableRef[string, LinearGradient]
 
 template failInvalid() =
   raise newException(PixieError, "Invalid SVG data")
@@ -116,13 +162,21 @@ proc attrOrDefault(node: XmlNode, name, default: string): string =
     result = default
 
 proc initCtx(): Ctx =
-  result.fill = parseHtmlColor("black").rgba
-  result.stroke = parseHtmlColor("black").rgba
+  result.display = true
+  try:
+    result.fill = parseHtmlColor("black").rgbx
+    result.stroke = parseHtmlColor("black").rgbx
+  except:
+    let e = getCurrentException()
+    raise newException(PixieError, e.msg, e)
   result.strokeWidth = 1
   result.transform = mat3()
   result.strokeMiterLimit = defaultMiterLimit
+  result.opacity = 1
+  result.strokeOpacity = 1
+  result.linearGradients = newTable[string, LinearGradient]()
 
-proc decodeCtx(inherited: Ctx, node: XmlNode): Ctx =
+proc decodeCtxInternal(inherited: Ctx, node: XmlNode): Ctx =
   result = inherited
 
   proc splitArgs(s: string): seq[string] =
@@ -143,6 +197,10 @@ proc decodeCtx(inherited: Ctx, node: XmlNode): Ctx =
     strokeDashArray = node.attr("stroke-dasharray")
     transform = node.attr("transform")
     style = node.attr("style")
+    display = node.attr("display")
+    opacity = node.attr("opacity")
+    fillOpacity = node.attr("fill-opacity")
+    strokeOpacity = node.attr("stroke-opacity")
 
   let pairs = style.split(';')
   for pair in pairs:
@@ -150,6 +208,9 @@ proc decodeCtx(inherited: Ctx, node: XmlNode): Ctx =
     if parts.len == 2:
       # Do not override element properties
       case parts[0].strip():
+      of "fill-rule":
+        if fillRule.len == 0:
+          fillRule = parts[1].strip()
       of "fill":
         if fill.len == 0:
           fill = parts[1].strip()
@@ -171,6 +232,35 @@ proc decodeCtx(inherited: Ctx, node: XmlNode): Ctx =
       of "stroke-dasharray":
         if strokeDashArray.len == 0:
           strokeDashArray = parts[1].strip()
+      of "display":
+        if display.len == 0:
+          display = parts[1].strip()
+      of "opacity":
+        if opacity.len == 0:
+          opacity = parts[1].strip()
+      of "fillOpacity":
+        if fillOpacity.len == 0:
+          fillOpacity = parts[1].strip()
+      of "strokeOpacity":
+        if strokeOpacity.len == 0:
+          strokeOpacity = parts[1].strip()
+      else:
+        discard
+    elif pair.len > 0:
+      when defined(pixieDebugSvg):
+        echo "Invalid style pair: ", pair
+
+  if display.len > 0:
+    result.display = display.strip() != "none"
+
+  if opacity.len > 0:
+    result.opacity = clamp(parseFloat(opacity), 0, 1)
+
+  if fillOpacity.len > 0:
+    result.fill.opacity = clamp(parseFloat(fillOpacity), 0, 1)
+
+  if strokeOpacity.len > 0:
+    result.strokeOpacity = clamp(parseFloat(strokeOpacity), 0, 1)
 
   if fillRule == "":
     discard # Inherit
@@ -186,18 +276,30 @@ proc decodeCtx(inherited: Ctx, node: XmlNode): Ctx =
   if fill == "" or fill == "currentColor":
     discard # Inherit
   elif fill == "none":
-    result.fill = ColorRGBA()
+    result.fill = ColorRGBX()
+  elif fill.startsWith("url("):
+    let id = fill[5 .. ^2]
+    if id in result.linearGradients:
+      let linearGradient = result.linearGradients[id]
+      result.fill = newPaint(pkGradientLinear)
+      result.fill.gradientHandlePositions = @[
+        result.transform * vec2(linearGradient.x1, linearGradient.y1),
+        result.transform * vec2(linearGradient.x2, linearGradient.y2)
+      ]
+      result.fill.gradientStops = linearGradient.stops
+    else:
+      raise newException(PixieError, "Missing SVG resource " & id)
   else:
-    result.fill = parseHtmlColor(fill).rgba
+    result.fill = parseHtmlColor(fill).rgbx
 
   if stroke == "":
     discard # Inherit
   elif stroke == "currentColor":
     result.shouldStroke = true
   elif stroke == "none":
-    result.stroke = ColorRGBA()
+    result.stroke = ColorRGBX()
   else:
-    result.stroke = parseHtmlColor(stroke).rgba
+    result.stroke = parseHtmlColor(stroke).rgbx
     result.shouldStroke = true
 
   if strokeWidth == "":
@@ -208,7 +310,7 @@ proc decodeCtx(inherited: Ctx, node: XmlNode): Ctx =
     result.strokeWidth = parseFloat(strokeWidth)
     result.shouldStroke = true
 
-  if result.stroke == ColorRGBA() or result.strokeWidth <= 0:
+  if result.stroke == ColorRGBX() or result.strokeWidth <= 0:
     result.shouldStroke = false
 
   if strokeLineCap == "":
@@ -262,7 +364,7 @@ proc decodeCtx(inherited: Ctx, node: XmlNode): Ctx =
   else:
     template failInvalidTransform(transform: string) =
       raise newException(
-          PixieError, "Unsupported SVG transform: " & transform & "."
+          PixieError, "Unsupported SVG transform: " & transform
         )
 
     var remaining = transform
@@ -320,6 +422,15 @@ proc decodeCtx(inherited: Ctx, node: XmlNode): Ctx =
       else:
         failInvalidTransform(transform)
 
+proc decodeCtx(inherited: Ctx, node: XmlNode): Ctx =
+  try:
+    decodeCtxInternal(inherited, node)
+  except PixieError as e:
+    raise e
+  except:
+    let e = getCurrentException()
+    raise newException(PixieError, e.msg, e)
+
 proc cairoLineCap(lineCap: LineCap): cairo.LineCap =
   case lineCap:
   of lcButt:
@@ -339,19 +450,24 @@ proc cairoLineJoin(lineJoin: LineJoin): cairo.LineJoin =
     LineJoinRound
 
 proc fill(c: ptr Context, ctx: Ctx, path: Path) {.inline.} =
-  # img.fillPath(path, ctx.fill, ctx.transform, ctx.fillRule)
-  prepare(c, path, ctx.fill, ctx.transform, ctx.fillRule)
-  c.fill()
+  if ctx.display and ctx.opacity > 0:
+    let paint = newPaint(ctx.fill)
+    paint.opacity = paint.opacity * ctx.opacity
+    prepare(c, path, paint, ctx.transform, ctx.fillRule)
+    c.fill()
 
 proc stroke(c: ptr Context, ctx: Ctx, path: Path) {.inline.} =
-  prepare(c, path, ctx.stroke, ctx.transform)
-  c.setLineWidth(ctx.strokeWidth)
-  c.setLineCap(ctx.strokeLineCap.cairoLineCap())
-  c.setLineJoin(ctx.strokeLineJoin.cairoLineJoin())
-  c.setMiterLimit(ctx.strokeMiterLimit)
-  c.stroke()
+  if ctx.display and ctx.opacity > 0:
+    let paint = newPaint(ctx.stroke)
+    paint.color.a *= (ctx.opacity * ctx.strokeOpacity)
+    prepare(c, path, paint, ctx.transform)
+    c.setLineWidth(ctx.strokeWidth)
+    c.setLineCap(ctx.strokeLineCap.cairoLineCap())
+    c.setLineJoin(ctx.strokeLineJoin.cairoLineJoin())
+    c.setMiterLimit(ctx.strokeMiterLimit)
+    c.stroke()
 
-proc draw(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
+proc drawInternal(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
   if node.kind != xnElement:
     # Skip <!-- comments -->
     return
@@ -364,7 +480,7 @@ proc draw(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
     let ctx = decodeCtx(ctxStack[^1], node)
     ctxStack.add(ctx)
     for child in node:
-      img.draw(child, ctxStack)
+      img.drawInternal(child, ctxStack)
     discard ctxStack.pop()
 
   of "path":
@@ -372,8 +488,8 @@ proc draw(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
       d = node.attr("d")
       ctx = decodeCtx(ctxStack[^1], node)
       path = parsePath(d)
-    if ctx.fill != ColorRGBA():
-      img.fill(ctx, path)
+
+    img.fill(ctx, path)
     if ctx.shouldStroke:
       img.stroke(ctx, path)
 
@@ -385,7 +501,7 @@ proc draw(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
       x2 = parseFloat(node.attrOrDefault("x2", "0"))
       y2 = parseFloat(node.attrOrDefault("y2", "0"))
 
-    var path: Path
+    let path = newPath()
     path.moveTo(x1, y1)
     path.lineTo(x2, y2)
 
@@ -414,7 +530,7 @@ proc draw(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
     if vecs.len == 0:
       failInvalid()
 
-    var path: Path
+    let path = newPath()
     path.moveTo(vecs[0])
     for i in 1 ..< vecs.len:
       path.lineTo(vecs[i])
@@ -423,9 +539,7 @@ proc draw(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
     # and fill or not
     if node.tag == "polygon":
       path.closePath()
-
-      if ctx.fill != ColorRGBA():
-        img.fill(ctx, path)
+      img.fill(ctx, path)
 
     if ctx.shouldStroke:
       img.stroke(ctx, path)
@@ -445,7 +559,7 @@ proc draw(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
       rx = max(parseFloat(node.attrOrDefault("rx", "0")), 0)
       ry = max(parseFloat(node.attrOrDefault("ry", "0")), 0)
 
-    var path: Path
+    let path = newPath()
     if rx > 0 or ry > 0:
       if rx == 0:
         rx = ry
@@ -466,8 +580,7 @@ proc draw(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
     else:
       path.rect(x, y, width, height)
 
-    if ctx.fill != ColorRGBA():
-      img.fill(ctx, path)
+    img.fill(ctx, path)
     if ctx.shouldStroke:
       img.stroke(ctx, path)
 
@@ -485,17 +598,25 @@ proc draw(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
       rx = parseFloat(node.attrOrDefault("rx", "0"))
       ry = parseFloat(node.attrOrDefault("ry", "0"))
 
-    var path: Path
+    let path = newPath()
     path.ellipse(cx, cy, rx, ry)
 
-    if ctx.fill != ColorRGBA():
-      img.fill(ctx, path)
+    img.fill(ctx, path)
     if ctx.shouldStroke:
       img.stroke(ctx, path)
 
   else:
     raise newException(PixieError, "Unsupported SVG tag: " & node.tag & ".")
 
+proc draw(img: ptr Context, node: XmlNode, ctxStack: var seq[Ctx]) =
+  try:
+    drawInternal(img, node, ctxStack)
+  except PixieError as e:
+    raise e
+  except:
+    let e = getCurrentException()
+    raise newException(PixieError, e.msg, e)
+
 proc decodeSvg*(data: string, width = 0, height = 0): Image =
   ## Render SVG file and return the image. Defaults to the SVG's view box size.
   try:
@@ -519,21 +640,21 @@ proc decodeSvg*(data: string, width = 0, height = 0): Image =
         vec2(-viewBoxMinX.float32, -viewBoxMinY.float32)
       )
 
-    var surface: ptr Surface
+    var
+      width = width
+      height = height
+      surface: ptr Surface
     if width == 0 and height == 0: # Default to the view box size
-      result = newImage(viewBoxWidth, viewBoxHeight)
-      surface = imageSurfaceCreate(
-        FORMAT_ARGB32, viewBoxWidth.int32, viewBoxHeight.int32
-      )
+      width = viewBoxWidth.int32
+      height = viewBoxHeight.int32
     else:
-      result = newImage(width, height)
-      surface = imageSurfaceCreate(FORMAT_ARGB32, width.int32, height.int32)
-
       let
         scaleX = width.float32 / viewBoxWidth.float32
         scaleY = height.float32 / viewBoxHeight.float32
       rootCtx.transform = rootCtx.transform * scale(vec2(scaleX, scaleY))
 
+    surface = imageSurfaceCreate(FORMAT_ARGB32, width.int32, height.int32)
+
     let c = surface.create()
 
     var ctxStack = @[rootCtx]
@@ -542,6 +663,8 @@ proc decodeSvg*(data: string, width = 0, height = 0): Image =
 
     surface.flush()
 
+    result = newImage(width, height)
+
     let pixels = cast[ptr UncheckedArray[array[4, uint8]]](surface.getData())
     for y in 0 ..< result.height:
       for x in 0 ..< result.width:

experiments/test_svg_cairo.nim

@@ -10,9 +10,19 @@ const files = [
   "ellipse01",
   "triangle01",
   "quad01",
-  "Ghostscript_Tiger"
+  "Ghostscript_Tiger",
+  "scale",
+  "miterlimit",
+  "dashes"
 ]
 
+proc doDiff(rendered: Image, name: string) =
+  rendered.writeFile(&"tests/fileformats/svg/rendered/{name}.png")
+  let
+    master = readImage(&"tests/fileformats/svg/masters/{name}.png")
+    (diffScore, diffImage) = diff(master, rendered)
+  echo &"{name} score: {diffScore}"
+  diffImage.writeFile(&"tests/fileformats/svg/diffs/{name}.png")
+
 for file in files:
-  let image = decodeSvg(readFile(&"tests/images/svg/{file}.svg"))
-  image.writeFile(&"tests/images/svg/{file}.png")
+  doDiff(decodeSvg(readFile(&"tests/fileformats/svg/{file}.svg")), file)

src/pixie/fileformats/svg.nim

@@ -329,15 +329,13 @@ proc decodeCtx(inherited: Ctx, node: XmlNode): Ctx =
 proc fill(img: Image, ctx: Ctx, path: Path) {.inline.} =
   if ctx.display and ctx.opacity > 0:
     let paint = newPaint(ctx.fill)
-    if ctx.opacity != 1:
-      paint.opacity = paint.opacity * ctx.opacity
+    paint.opacity = paint.opacity * ctx.opacity
     img.fillPath(path, paint, ctx.transform, ctx.fillRule)
 
 proc stroke(img: Image, ctx: Ctx, path: Path) {.inline.} =
   if ctx.display and ctx.opacity > 0:
     let paint = newPaint(ctx.stroke)
-    if ctx.opacity != 1:
-      paint.color.a *= (ctx.opacity * ctx.strokeOpacity)
+    paint.color.a *= (ctx.opacity * ctx.strokeOpacity)
     img.strokePath(
       path,
       paint,

src/pixie/paths.nim

@@ -46,6 +46,7 @@ type
 
 const
   epsilon: float64 = 0.0001 * PI ## Tiny value used for some computations. Must be float64 to prevent leaks.
+  pixelErrorMargin: float32 = 0.2
   defaultMiterLimit*: float32 = 4
 
 when defined(release):
@@ -639,7 +640,7 @@ proc polygon*(
   path.polygon(pos.x, pos.y, size, sides)
 
 proc commandsToShapes(
-  path: Path, closeSubpaths = false, pixelScale: float32 = 1.0
+  path: Path, closeSubpaths: bool, pixelScale: float32
 ): seq[seq[Vec2]] =
   ## Converts SVG-like commands to sequences of vectors.
   var
@@ -651,7 +652,7 @@ proc commandsToShapes(
     prevCommandKind = Move
     prevCtrl, prevCtrl2: Vec2
 
-  let errorMarginSq = pow(0.2.float32 / pixelScale, 2)
+  let errorMarginSq = pow(pixelErrorMargin / pixelScale, 2)
 
   proc addSegment(shape: var seq[Vec2], at, to: Vec2) =
     # Don't add any 0 length lines
@@ -1080,7 +1081,7 @@ proc computeBounds*(
   path: Path, transform = mat3()
 ): Rect {.raises: [PixieError].} =
   ## Compute the bounds of the path.
-  var shapes = path.commandsToShapes()
+  var shapes = path.commandsToShapes(true, pixelScale(transform))
   shapes.transform(transform)
   computeBounds(shapes.shapesToSegments())
 
@@ -1135,23 +1136,18 @@ proc maxEntryCount(partitioning: Partitioning): int =
   for i in 0 ..< partitioning.partitions.len:
     result = max(result, partitioning.partitions[i].len)
 
-proc insertionSort(
-  hits: var seq[(float32, int16)], lo, hi: int
-) {.inline.} =
-  for i in lo + 1 .. hi:
-    var
-      j = i - 1
-      k = i
-    while j >= 0 and hits[j][0] > hits[k][0]:
-      swap(hits[j + 1], hits[j])
-      dec j
-      dec k
-
-proc sort(hits: var seq[(float32, int16)], inl, inr: int) =
+proc sortHits(hits: var seq[(float32, int16)], inl, inr: int) =
   ## Quicksort + insertion sort, in-place and faster than standard lib sort.
   let n = inr - inl + 1
-  if n < 32:
-    insertionSort(hits, inl, inr)
+  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 hits[j][0] > hits[k][0]:
+        swap(hits[j + 1], hits[j])
+        dec j
+        dec k
     return
   var
     l = inl
@@ -1166,8 +1162,8 @@ proc sort(hits: var seq[(float32, int16)], inl, inr: int) =
       swap(hits[l], hits[r])
       inc l
       dec r
-  sort(hits, inl, r)
-  sort(hits, l, inr)
+  sortHits(hits, inl, r)
+  sortHits(hits, l, inr)
 
 proc shouldFill(
   windingRule: WindingRule, count: int
@@ -1257,7 +1253,7 @@ proc computeCoverage(
         inc numHits
 
     if numHits > 0:
-      sort(hits, 0, numHits - 1)
+      sortHits(hits, 0, numHits - 1)
 
     if aa:
       for (prevAt, at, count) in hits.walk(numHits, windingRule, y, width):
@@ -1657,7 +1653,8 @@ proc strokeShapes(
   lineCap: LineCap,
   lineJoin: LineJoin,
   miterLimit: float32,
-  dashes: seq[float32]
+  dashes: seq[float32],
+  pixelScale: float32
 ): seq[seq[Vec2]] =
   if strokeWidth <= 0:
     return
@@ -1669,7 +1666,7 @@ proc strokeShapes(
   proc makeCircle(at: Vec2): seq[Vec2] =
     let path = newPath()
     path.ellipse(at, halfStroke, halfStroke)
-    path.commandsToShapes()[0]
+    path.commandsToShapes(true, pixelScale)[0]
 
   proc makeRect(at, to: Vec2): seq[Vec2] =
     # Rectangle corners
@@ -1695,7 +1692,15 @@ proc strokeShapes(
 
     @[a, b, c, d, a]
 
-  proc makeJoin(prevPos, pos, nextPos: Vec2): seq[Vec2] =
+  proc addJoin(shape: var seq[seq[Vec2]], prevPos, pos, nextPos: Vec2) =
+    let minArea = pixelErrorMargin / pixelScale
+
+    if lineJoin == ljRound:
+      let area = PI.float32 * halfStroke * halfStroke
+      if area > minArea:
+        shape.add makeCircle(pos)
+      return
+
     let angle = fixAngle(angle(nextPos - pos) - angle(prevPos - pos))
     if abs(abs(angle) - PI) > epsilon:
       var
@@ -1719,13 +1724,21 @@ proc strokeShapes(
           lb = line(nextPos + b, pos + b)
         var at: Vec2
         if la.intersects(lb, at):
-          return @[pos + a, at, pos + b, pos, pos + a]
+          let
+            bisectorLengthSq = (at - pos).lengthSq
+            areaSq = 0.25.float32 * (
+              a.lengthSq * bisectorLengthSq + b.lengthSq * bisectorLengthSq
+            )
+          if areaSq > (minArea * minArea):
+            shape.add @[pos + a, at, pos + b, pos, pos + a]
 
       of ljBevel:
-        return @[a + pos, b + pos, pos, a + pos]
+        let areaSq = 0.25.float32 * a.lengthSq * b.lengthSq
+        if areaSq > (minArea * minArea):
+          shape.add @[a + pos, b + pos, pos, a + pos]
 
       of ljRound:
-        return makeCircle(pos)
+        discard # Handled above, skipping angle calculation
 
   for shape in shapes:
     var shapeStroke: seq[seq[Vec2]]
@@ -1773,10 +1786,10 @@ proc strokeShapes(
 
       # If we need a line join
       if i < shape.len - 1:
-        shapeStroke.add(makeJoin(prevPos, pos, shape[i + 1]))
+        shapeStroke.addJoin(prevPos, pos, shape[i + 1])
 
     if shape[0] == shape[^1]:
-      shapeStroke.add(makeJoin(shape[^2], shape[^1], shape[1]))
+      shapeStroke.addJoin(shape[^2], shape[^1], shape[1])
     else:
       case lineCap:
       of lcButt:
@@ -1793,7 +1806,7 @@ proc strokeShapes(
     result.add(shapeStroke)
 
 proc parseSomePath(
-  path: SomePath, closeSubpaths: bool, pixelScale: float32 = 1.0
+  path: SomePath, closeSubpaths: bool, pixelScale: float32
 ): seq[seq[Vec2]] {.inline.} =
   ## Given SomePath, parse it in different ways.
   when type(path) is string:
@@ -1874,13 +1887,15 @@ proc strokePath*(
   blendMode = bmNormal
 ) {.raises: [PixieError].} =
   ## Strokes a path.
+  let pixelScale = transform.pixelScale()
   var strokeShapes = strokeShapes(
-    parseSomePath(path, false, transform.pixelScale()),
+    parseSomePath(path, false, pixelScale),
     strokeWidth,
     lineCap,
     lineJoin,
     miterLimit,
-    dashes
+    dashes,
+    pixelScale
   )
   strokeShapes.transform(transform)
   mask.fillShapes(strokeShapes, wrNonZero, blendMode)
@@ -1908,7 +1923,8 @@ proc strokePath*(
         lineCap,
         lineJoin,
         miterLimit,
-        dashes
+        dashes,
+        pixelScale(transform)
       )
       strokeShapes.transform(transform)
       var color = paint.color
@@ -1970,7 +1986,7 @@ proc overlaps(
         if segment.to != at:
           hits.add((at.x, winding))
 
-  sort(hits, 0, hits.high)
+  sortHits(hits, 0, hits.high)
 
   var count: int
   for (at, winding) in hits:
@@ -1985,7 +2001,7 @@ proc fillOverlaps*(
   windingRule = wrNonZero
 ): bool {.raises: [PixieError].} =
   ## Returns whether or not the specified point is contained in the current path.
-  var shapes = parseSomePath(path, true, transform.pixelScale())
+  var shapes = path.commandsToShapes(true, transform.pixelScale())
   shapes.transform(transform)
   shapes.overlaps(test, windingRule)
 
@@ -2001,13 +2017,15 @@ proc strokeOverlaps*(
 ): bool {.raises: [PixieError].} =
   ## Returns whether or not the specified point is inside the area contained
   ## by the stroking of a path.
+  let pixelScale = transform.pixelScale()
   var strokeShapes = strokeShapes(
-    parseSomePath(path, false, transform.pixelScale()),
+    path.commandsToShapes(false, pixelScale),
     strokeWidth,
     lineCap,
     lineJoin,
     miterLimit,
-    dashes
+    dashes,
+    pixelScale
   )
   strokeShapes.transform(transform)
   strokeShapes.overlaps(test, wrNonZero)

tests/benchmark_fonts.nim

@@ -12,7 +12,7 @@ let
 timeIt "typeset":
   discard font.typeset(text, bounds = vec2(image.width.float32, 0))
 
-timeIt "rasterize":
+timeIt "fill text":
   image.fill(rgba(255, 255, 255, 255))
   image.fillText(font, text, bounds = vec2(image.width.float32, 0))
   # mask.fill(0)

tests/fileformats/svg/accessibility-outline.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><circle fill="none" stroke="#000" stroke-linejoin="round" stroke-width="32" cx="256" cy="56" r="40"/><path fill="none" stroke="#000" stroke-linejoin="round" stroke-width="32" d="M204.23,274.44c2.9-18.06,4.2-35.52-.5-47.59-4-10.38-12.7-16.19-23.2-20.15L88,176.76c-12-4-23.21-10.7-24-23.94-1-17,14-28,29-24,0,0,88,31.14,163,31.14s162-31,162-31c18-5,30,9,30,23.79,0,14.21-11,19.21-24,23.94l-88,31.91c-8,3-21,9-26,18.18-6,10.75-5,29.53-2.1,47.59l5.9,29.63L351.21,467.9c2.8,13.15-6.3,25.44-19.4,27.74S308,489,304.12,476.28L266.56,360.35q-2.71-8.34-4.8-16.87L256,320l-5.3,21.65q-2.52,10.35-5.8,20.48L208,476.18c-4,12.85-14.5,21.75-27.6,19.46S158,480.05,160.94,467.9l37.39-163.83Z"/></svg>

tests/test_paths.nim

@@ -605,7 +605,7 @@ block:
   doAssert not path.strokeOverlaps(vec2(0, 0))
   doAssert not path.strokeOverlaps(vec2(20, 20))
   doAssert path.strokeOverlaps(vec2(0, 20))
-  doAssert path.strokeOverlaps(vec2(40, 20))
+  doAssert path.strokeOverlaps(vec2(39.9, 19.9))
   doAssert path.strokeOverlaps(vec2(19.8, 30.2))
   doAssert not path.strokeOverlaps(vec2(19.4, 30.6))
 

tests/test_svg.nim

@@ -26,3 +26,8 @@ proc doDiff(rendered: Image, name: string) =
 
 for file in files:
   doDiff(decodeSvg(readFile(&"tests/fileformats/svg/{file}.svg")), file)
+
+doDiff(
+  decodeSvg(readFile("tests/fileformats/svg/accessibility-outline.svg"), 512, 512),
+  "accessibility-outline"
+)