diff --git a/docs/index.html b/docs/index.html
index 0cfe5f8..916d42c 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -213,8 +213,8 @@ YutilsAn ASS typeset utilities library
Splits lines of shape shape into shorter ones to fix to maximal line length of max_len, creating a new shape.
-outline_shape = shape.to_outline(shape, width_xy[, width_y])
-Converts shape shape from his filling to the stroke with horizontal width width_xy and vertical width width_y, returned as new shape. If width_y isn't defined, width_xy stands for both.
+outline_shape = shape.to_outline(shape, width_xy[, width_y][, mode])
+Converts shape shape from his filling to the stroke with horizontal width width_xy, vertical width width_y and join type mode which can be "round"|"bevel"|"miter", returned as new shape. If width_y isn't defined, width_xy stands for both. Default join type is "round".
pixels = shape.to_pixels(shape)
diff --git a/src/Yutils.lua b/src/Yutils.lua
index df6f8fd..a78d06d 100644
--- a/src/Yutils.lua
+++ b/src/Yutils.lua
@@ -19,7 +19,7 @@
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
-----------------------------------------------------------------------------------------------------------------
- Version: 26th October 2014, 19:10 (GMT+1)
+ Version: 4th November 2014, 04:00 (GMT+1)
Yutils
table
@@ -60,7 +60,7 @@
glue(src_shape, dst_shape[, transform_callback]) -> string
move(shape, x, y) -> string
split(shape, max_len) -> string
- to_outline(shape, width_xy[, width_y]) -> string
+ to_outline(shape, width_xy[, width_y][, mode]) -> string
to_pixels(shape) -> table
transform(shape, matrix) -> string
ass
@@ -113,6 +113,7 @@
local FP_PRECISION = 3 -- Floating point precision by numbers behind point (for shape points)
local CURVE_TOLERANCE = 1 -- Angle in degree to define a curve as flat
local MAX_CIRCUMFERENCE = 1.5 -- Circumference step size to create round edges out of lines
+local MITER_LIMIT = 200 -- Maximal length of a miter join
local SUPERSAMPLING = 8 -- Anti-aliasing precision for shape to pixels conversion
local FONT_PRECISION = 64 -- Font scale for better precision output from native font system
local LIBASS_FONTHACK = true -- Scale font data to fontsize? (no effect on windows)
@@ -1591,12 +1592,14 @@ Yutils = {
return table.concat(new_shape, " ")
end,
-- Converts shape to stroke version
- to_outline = function(shape, width_xy, width_y)
+ to_outline = function(shape, width_xy, width_y, mode)
-- Check arguments
- if type(shape) ~= "string" or type(width_xy) ~= "number" or width_xy < 0 or not (width_y == nil or type(width_y) == "number" and width_y >= 0) then
- error("shape and line width (general or horizontal and vertical) expected", 2)
- elseif width_y and not (width_xy > 0 or width_y > 0) or width_xy == 0 then
+ if type(shape) ~= "string" or type(width_xy) ~= "number" or width_y ~= nil and type(width_y) ~= "number" or mode ~= nil and type(mode) ~= "string" then
+ error("shape, line width (general or horizontal and vertical) and optional mode expected", 2)
+ elseif width_y and (width_xy < 0 or width_y < 0 or not (width_xy > 0 or width_y > 0)) or width_xy <= 0 then
error("one width must be >0", 2)
+ elseif mode and mode ~= "round" and mode ~= "bevel" and mode ~= "miter" then
+ error("valid mode expected", 2)
end
-- Line width values
local width, xscale, yscale
@@ -1694,25 +1697,67 @@ Yutils = {
o_vec1_x, o_vec1_y = Yutils.math.stretch(o_vec1_x, o_vec1_y, 0, width)
local o_vec2_x, o_vec2_y = Yutils.math.ortho(post_point[1]-point[1], post_point[2]-point[2], 0, 0, 0, 1)
o_vec2_x, o_vec2_y = Yutils.math.stretch(o_vec2_x, o_vec2_y, 0, width)
- -- Calculate degree & circumference between orthogonal vectors
- local degree = Yutils.math.degree(o_vec1_x, o_vec1_y, 0, o_vec2_x, o_vec2_y, 0)
- local circ = math.abs(math.rad(degree)) * width
-- Add first edge point
outline_n = outline_n + 1
outline[outline_n] = string.format("%s%s %s",
- outline_n == 1 and "m " or outline_n == 2 and "l " or "",
+ outline_n == 1 and "m " or "",
Yutils.math.round(point[1] + o_vec1_x * xscale, FP_PRECISION), Yutils.math.round(point[2] + o_vec1_y * yscale, FP_PRECISION))
- -- Round edge needed?
- if circ > MAX_CIRCUMFERENCE then
- local circ_rest = circ % MAX_CIRCUMFERENCE
- for cur_circ = circ_rest > 0 and circ_rest or MAX_CIRCUMFERENCE, circ, MAX_CIRCUMFERENCE do
- local curve_vec_x, curve_vec_y = rotate2d(o_vec1_x, o_vec1_y, cur_circ / circ * degree)
+ -- Create join by mode
+ if mode == "bevel" then
+ -- Nothing to add!
+ elseif mode == "miter" then
+ -- Add mid edge point(s)
+ local vec1_x, vec1_y, vec2_x, vec2_y = point[1]-pre_point[1], point[2]-pre_point[2], point[1]-post_point[1], point[2]-post_point[2]
+ local delta = vec1_x * vec2_y - vec2_x * vec1_y
+ if delta == 0 then -- Parallel vectors
+ vec1_x, vec1_y = Yutils.math.stretch(vec1_x, vec1_y, 0, MITER_LIMIT)
+ vec2_x, vec2_y = Yutils.math.stretch(vec2_x, vec2_y, 0, MITER_LIMIT)
outline_n = outline_n + 1
- outline[outline_n] = string.format("%s%s %s",
- outline_n == 1 and "m " or outline_n == 2 and "l " or "",
- Yutils.math.round(point[1] + curve_vec_x * xscale, FP_PRECISION), Yutils.math.round(point[2] + curve_vec_y * yscale, FP_PRECISION))
+ outline[outline_n] = string.format("%s%s %s %s %s",
+ outline_n == 2 and "l " or "",
+ Yutils.math.round(point[1] + (o_vec1_x + vec1_x) * xscale, FP_PRECISION), Yutils.math.round(point[2] + (o_vec1_y + vec1_y) * yscale, FP_PRECISION),
+ Yutils.math.round(point[1] + (o_vec2_x + vec2_x) * xscale, FP_PRECISION), Yutils.math.round(point[2] + (o_vec2_y + vec2_y) * yscale, FP_PRECISION))
+ else -- Vectors intersect
+ local pre, post = (point[1] + o_vec1_x) * (point[2] + o_vec1_y + vec1_y) - (point[1] + o_vec1_x + vec1_x) * (point[2] + o_vec1_y),
+ (point[1] + o_vec2_x) * (point[2] + o_vec2_y + vec2_y) - (point[1] + o_vec2_x + vec2_x) * (point[2] + o_vec2_y)
+ local is_vec_x, is_vec_y = (pre * -vec2_x - post * -vec1_x) / delta - point[1], (pre * -vec2_y - post * -vec1_y) / delta - point[2]
+ local is_vec_len = Yutils.math.distance(is_vec_x, is_vec_y)
+ if is_vec_len > MITER_LIMIT then
+ local fix_scale = MITER_LIMIT / is_vec_len
+ outline_n = outline_n + 1
+ outline[outline_n] = string.format("%s%s %s %s %s",
+ outline_n == 2 and "l " or "",
+ Yutils.math.round(point[1] + (o_vec1_x + (is_vec_x - o_vec1_x) * fix_scale) * xscale, FP_PRECISION), Yutils.math.round(point[2] + (o_vec1_y + (is_vec_y - o_vec1_y) * fix_scale) * yscale, FP_PRECISION),
+ Yutils.math.round(point[1] + (o_vec2_x + (is_vec_x - o_vec2_x) * fix_scale) * xscale, FP_PRECISION), Yutils.math.round(point[2] + (o_vec2_y + (is_vec_y - o_vec2_y) * fix_scale) * yscale, FP_PRECISION))
+ else
+ outline_n = outline_n + 1
+ outline[outline_n] = string.format("%s%s %s",
+ outline_n == 2 and "l " or "",
+ Yutils.math.round(point[1] + is_vec_x * xscale, FP_PRECISION), Yutils.math.round(point[2] + is_vec_y * yscale, FP_PRECISION))
+ end
+ end
+ else -- not mode or mode == "round"
+ -- Calculate degree & circumference between orthogonal vectors
+ local degree = Yutils.math.degree(o_vec1_x, o_vec1_y, 0, o_vec2_x, o_vec2_y, 0)
+ local circ = math.abs(math.rad(degree)) * width
+ -- Join needed?
+ if circ > MAX_CIRCUMFERENCE then
+ -- Add curve edge points
+ local circ_rest = circ % MAX_CIRCUMFERENCE
+ for cur_circ = circ_rest > 0 and circ_rest or MAX_CIRCUMFERENCE, circ - MAX_CIRCUMFERENCE, MAX_CIRCUMFERENCE do
+ local curve_vec_x, curve_vec_y = rotate2d(o_vec1_x, o_vec1_y, cur_circ / circ * degree)
+ outline_n = outline_n + 1
+ outline[outline_n] = string.format("%s%s %s",
+ outline_n == 2 and "l " or "",
+ Yutils.math.round(point[1] + curve_vec_x * xscale, FP_PRECISION), Yutils.math.round(point[2] + curve_vec_y * yscale, FP_PRECISION))
+ end
end
end
+ -- Add end edge point
+ outline_n = outline_n + 1
+ outline[outline_n] = string.format("%s%s %s",
+ outline_n == 2 and "l " or "",
+ Yutils.math.round(point[1] + o_vec2_x * xscale, FP_PRECISION), Yutils.math.round(point[2] + o_vec2_y * yscale, FP_PRECISION))
end
-- Insert inner or outer outline to stroke shape
stroke_shape_n = stroke_shape_n + 1
diff --git a/tests/shape.lua b/tests/shape.lua
index d4201c8..8e9a08f 100644
--- a/tests/shape.lua
+++ b/tests/shape.lua
@@ -9,7 +9,7 @@ print("Flattened shape: " .. Yutils.shape.flatten(shape))
print("Moved shape: " .. Yutils.shape.move(shape, 5, -2))
print("Mirrored shape: " .. Yutils.shape.transform(shape, Yutils.math.create_matrix().rotate("y", 180)))
print("Shape with splitted lines: " .. Yutils.shape.split(shape, 15))
-print("Shape outline: " .. Yutils.shape.to_outline(Yutils.shape.flatten(shape), 5.5, 10))
+print("Shape outline: " .. Yutils.shape.to_outline(Yutils.shape.flatten(shape), 5.5, 10, "miter"))
print("Pixels:\n" .. Yutils.table.tostring(Yutils.shape.to_pixels("m -4.5 -4 l 0 -4 0 0")))
print(
"Detected shapes:\n" ..