Class | Magick::Draw |
In: |
lib/RMagick.rb
|
Parent: | Object |
ALIGN_TYPE_NAMES | = | { LeftAlign.to_i => 'left', RightAlign.to_i => 'right', CenterAlign.to_i => 'center' | Thse hashes are used to map Magick constant values to the strings used in the primitives. | |
ANCHOR_TYPE_NAMES | = | { StartAnchor.to_i => 'start', MiddleAnchor.to_i => 'middle', EndAnchor.to_i => 'end' | ||
DECORATION_TYPE_NAMES | = | { NoDecoration.to_i => 'none', UnderlineDecoration.to_i => 'underline', OverlineDecoration.to_i => 'overline', LineThroughDecoration.to_i => 'line-through' | ||
FONT_WEIGHT_NAMES | = | { AnyWeight.to_i => 'all', NormalWeight.to_i => 'normal', BoldWeight.to_i => 'bold', BolderWeight.to_i => 'bolder', LighterWeight.to_i => 'lighter', }.freeze | ||
GRAVITY_NAMES | = | { NorthWestGravity.to_i => 'northwest', NorthGravity.to_i => 'north', NorthEastGravity.to_i => 'northeast', WestGravity.to_i => 'west', CenterGravity.to_i => 'center', EastGravity.to_i => 'east', SouthWestGravity.to_i => 'southwest', SouthGravity.to_i => 'south', SouthEastGravity.to_i => 'southeast' | ||
PAINT_METHOD_NAMES | = | { PointMethod.to_i => 'point', ReplaceMethod.to_i => 'replace', FloodfillMethod.to_i => 'floodfill', FillToBorderMethod.to_i => 'filltoborder', ResetMethod.to_i => 'reset' | ||
STRETCH_TYPE_NAMES | = | { NormalStretch.to_i => 'normal', UltraCondensedStretch.to_i => 'ultra-condensed', ExtraCondensedStretch.to_i => 'extra-condensed', CondensedStretch.to_i => 'condensed', SemiCondensedStretch.to_i => 'semi-condensed', SemiExpandedStretch.to_i => 'semi-expanded', ExpandedStretch.to_i => 'expanded', ExtraExpandedStretch.to_i => 'extra-expanded', UltraExpandedStretch.to_i => 'ultra-expanded', AnyStretch.to_i => 'all' | ||
STYLE_TYPE_NAMES | = | { NormalStyle.to_i => 'normal', ItalicStyle.to_i => 'italic', ObliqueStyle.to_i => 'oblique', AnyStyle.to_i => 'all' |
Apply coordinate transformations to support scaling (s), rotation (r), and translation (t). Angles are specified in radians.
# File lib/RMagick.rb, line 218 218: def affine(sx, rx, ry, sy, tx, ty) 219: primitive "affine " + sprintf("%g,%g,%g,%g,%g,%g", sx, rx, ry, sy, tx, ty) 220: end
# File lib/RMagick.rb, line 229 229: def bezier(*points) 230: if points.length == 0 231: Kernel.raise ArgumentError, "no points specified" 232: elsif points.length % 2 != 0 233: Kernel.raise ArgumentError, "odd number of arguments specified" 234: end 235: primitive "bezier " + points.join(',') 236: end
Define the clipping rule.
# File lib/RMagick.rb, line 249 249: def clip_rule(rule) 250: if ( not ["evenodd", "nonzero"].include?(rule.downcase) ) 251: Kernel.raise ArgumentError, "Unknown clipping rule #{rule}" 252: end 253: primitive "clip-rule #{rule}" 254: end
Define the clip units
# File lib/RMagick.rb, line 257 257: def clip_units(unit) 258: if ( not ["userspace", "userspaceonuse", "objectboundingbox"].include?(unit.downcase) ) 259: Kernel.raise ArgumentError, "Unknown clip unit #{unit}" 260: end 261: primitive "clip-units #{unit}" 262: end
Set color in image according to specified colorization rule. Rule is one of point, replace, floodfill, filltoborder,reset
# File lib/RMagick.rb, line 266 266: def color(x, y, method) 267: if ( not PAINT_METHOD_NAMES.has_key?(method.to_i) ) 268: Kernel.raise ArgumentError, "Unknown PaintMethod: #{method}" 269: end 270: primitive "color #{x},#{y},#{PAINT_METHOD_NAMES[method.to_i]}" 271: end
Specify EITHER the text decoration (none, underline, overline, line-through) OR the text solid background color (any color name or spec)
# File lib/RMagick.rb, line 275 275: def decorate(decoration) 276: if ( DECORATION_TYPE_NAMES.has_key?(decoration.to_i) ) 277: primitive "decorate #{DECORATION_TYPE_NAMES[decoration.to_i]}" 278: else 279: primitive "decorate #{enquote(decoration)}" 280: end 281: end
Define a clip-path. A clip-path is a sequence of primitives bracketed by the "push clip-path <name>" and "pop clip-path" primitives. Upon advice from the IM guys, we also bracket the clip-path primitives with "push(pop) defs" and "push (pop) graphic-context".
# File lib/RMagick.rb, line 288 288: def define_clip_path(name) 289: begin 290: push('defs') 291: push('clip-path', name) 292: push('graphic-context') 293: yield 294: ensure 295: pop('graphic-context') 296: pop('clip-path') 297: pop('defs') 298: end 299: end
Let anything through, but the only defined argument is "UTF-8". All others are apparently ignored.
# File lib/RMagick.rb, line 309 309: def encoding(encoding) 310: primitive "encoding #{encoding}" 311: end
# File lib/RMagick.rb, line 325 325: def fill_rule(rule) 326: if ( not ["evenodd", "nonzero"].include?(rule.downcase) ) 327: Kernel.raise ArgumentError, "Unknown fill rule #{rule}" 328: end 329: primitive "fill-rule #{rule}" 330: end
# File lib/RMagick.rb, line 337 337: def font_family(name) 338: primitive "font-family \'#{name}\'" 339: end
# File lib/RMagick.rb, line 341 341: def font_stretch(stretch) 342: if ( not STRETCH_TYPE_NAMES.has_key?(stretch.to_i) ) 343: Kernel.raise ArgumentError, "Unknown stretch type" 344: end 345: primitive "font-stretch #{STRETCH_TYPE_NAMES[stretch.to_i]}" 346: end
# File lib/RMagick.rb, line 348 348: def font_style(style) 349: if ( not STYLE_TYPE_NAMES.has_key?(style.to_i) ) 350: Kernel.raise ArgumentError, "Unknown style type" 351: end 352: primitive "font-style #{STYLE_TYPE_NAMES[style.to_i]}" 353: end
The font weight argument can be either a font weight constant or [100,200,…,900]
# File lib/RMagick.rb, line 357 357: def font_weight(weight) 358: if ( FONT_WEIGHT_NAMES.has_key?(weight.to_i) ) 359: primitive "font-weight #{FONT_WEIGHT_NAMES[weight.to_i]}" 360: else 361: primitive "font-weight #{weight}" 362: end 363: end
Specify the text positioning gravity, one of: NorthWest, North, NorthEast, West, Center, East, SouthWest, South, SouthEast
# File lib/RMagick.rb, line 367 367: def gravity(grav) 368: if ( not GRAVITY_NAMES.has_key?(grav.to_i) ) 369: Kernel.raise ArgumentError, "Unknown text positioning gravity" 370: end 371: primitive "gravity #{GRAVITY_NAMES[grav.to_i]}" 372: end
IM 6.4.8-3 and later
# File lib/RMagick.rb, line 375 375: def interword_spacing(space) 376: begin 377: Float(space) 378: rescue ArgumentError 379: Kernel.raise ArgumentError, "invalid value for interword_spacing" 380: rescue TypeError 381: Kernel.raise TypeError, "can't convert #{space.class} into Float" 382: end 383: primitive "interword-spacing #{space}" 384: end
IM 6.4.8-3 and later
# File lib/RMagick.rb, line 387 387: def kerning(space) 388: begin 389: Float(space) 390: rescue ArgumentError 391: Kernel.raise ArgumentError, "invalid value for kerning" 392: rescue TypeError 393: Kernel.raise TypeError, "can't convert #{space.class} into Float" 394: end 395: primitive "kerning #{space}" 396: end
Set matte (make transparent) in image according to the specified colorization rule
# File lib/RMagick.rb, line 405 405: def matte(x, y, method) 406: if ( not PAINT_METHOD_NAMES.has_key?(method.to_i) ) 407: Kernel.raise ArgumentError, "Unknown paint method" 408: end 409: primitive "matte #{x},#{y} #{PAINT_METHOD_NAMES[method.to_i]}" 410: end
Specify drawing fill and stroke opacities. If the value is a string ending with a %, the number will be multiplied by 0.01.
# File lib/RMagick.rb, line 414 414: def opacity(opacity) 415: if (Numeric === opacity) 416: if (opacity < 0 || opacity > 1.0) 417: Kernel.raise ArgumentError, "opacity must be >= 0 and <= 1.0" 418: end 419: end 420: primitive "opacity #{opacity}" 421: end
Define a pattern. In the block, call primitive methods to draw the pattern. Reference the pattern by using its name as the argument to the ‘fill’ or ‘stroke’ methods
# File lib/RMagick.rb, line 433 433: def pattern(name, x, y, width, height) 434: begin 435: push('defs') 436: push("pattern #{name} #{x} #{y} #{width} #{height}") 437: push('graphic-context') 438: yield 439: ensure 440: pop('graphic-context') 441: pop('pattern') 442: pop('defs') 443: end 444: end
# File lib/RMagick.rb, line 459 459: def polygon(*points) 460: if points.length == 0 461: Kernel.raise ArgumentError, "no points specified" 462: elsif points.length % 2 != 0 463: Kernel.raise ArgumentError, "odd number of points specified" 464: end 465: primitive "polygon " + points.join(',') 466: end
# File lib/RMagick.rb, line 469 469: def polyline(*points) 470: if points.length == 0 471: Kernel.raise ArgumentError, "no points specified" 472: elsif points.length % 2 != 0 473: Kernel.raise ArgumentError, "odd number of points specified" 474: end 475: primitive "polyline " + points.join(',') 476: end
Return to the previously-saved set of whatever pop(‘graphic-context’) (the default if no arguments) pop(‘defs’) pop(‘gradient’) pop(‘pattern’)
# File lib/RMagick.rb, line 484 484: def pop(*what) 485: if what.length == 0 486: primitive "pop graphic-context" 487: else 488: # to_s allows a Symbol to be used instead of a String 489: primitive "pop " + what.map {|w| w.to_s}.join(' ') 490: end 491: end
Push the current set of drawing options. Also you can use push(‘graphic-context’) (the default if no arguments) push(‘defs’) push(‘gradient’) push(‘pattern’)
# File lib/RMagick.rb, line 498 498: def push(*what) 499: if what.length == 0 500: primitive "push graphic-context" 501: else 502: # to_s allows a Symbol to be used instead of a String 503: primitive "push " + what.map {|w| w.to_s}.join(' ') 504: end 505: end
Specify coordinate space rotation. "angle" is measured in degrees
# File lib/RMagick.rb, line 514 514: def rotate(angle) 515: primitive "rotate #{angle}" 516: end
Specify scaling to be applied to coordinate space on subsequent drawing commands.
# File lib/RMagick.rb, line 525 525: def scale(x, y) 526: primitive "scale #{x},#{y}" 527: end
# File lib/RMagick.rb, line 551 551: def stroke_dasharray(*list) 552: if list.length == 0 553: primitive "stroke-dasharray none" 554: else 555: list.each { |x| 556: if x <= 0 then 557: Kernel.raise ArgumentError, "dash array elements must be > 0 (#{x} given)" 558: end 559: } 560: primitive "stroke-dasharray #{list.join(',')}" 561: end 562: end
# File lib/RMagick.rb, line 569 569: def stroke_linecap(value) 570: if ( not ["butt", "round", "square"].include?(value.downcase) ) 571: Kernel.raise ArgumentError, "Unknown linecap type: #{value}" 572: end 573: primitive "stroke-linecap #{value}" 574: end
# File lib/RMagick.rb, line 576 576: def stroke_linejoin(value) 577: if ( not ["round", "miter", "bevel"].include?(value.downcase) ) 578: Kernel.raise ArgumentError, "Unknown linejoin type: #{value}" 579: end 580: primitive "stroke-linejoin #{value}" 581: end
# File lib/RMagick.rb, line 583 583: def stroke_miterlimit(value) 584: if (value < 1) 585: Kernel.raise ArgumentError, "miterlimit must be >= 1" 586: end 587: primitive "stroke-miterlimit #{value}" 588: end
Draw text at position x,y. Add quotes to text that is not already quoted.
# File lib/RMagick.rb, line 602 602: def text(x, y, text) 603: if text.to_s.empty? 604: Kernel.raise ArgumentError, "missing text argument" 605: end 606: if text.length > 2 && /\A(?:\"[^\"]+\"|\'[^\']+\'|\{[^\}]+\})\z/.match(text) 607: ; # text already quoted 608: elsif !text['\''] 609: text = '\''+text+'\'' 610: elsif !text['"'] 611: text = '"'+text+'"' 612: elsif !(text['{'] || text['}']) 613: text = '{'+text+'}' 614: else 615: # escape existing braces, surround with braces 616: text = '{' + text.gsub(/[}]/) { |b| '\\' + b } + '}' 617: end 618: primitive "text #{x},#{y} #{text}" 619: end
Specify text alignment relative to a given point
# File lib/RMagick.rb, line 622 622: def text_align(alignment) 623: if ( not ALIGN_TYPE_NAMES.has_key?(alignment.to_i) ) 624: Kernel.raise ArgumentError, "Unknown alignment constant: #{alignment}" 625: end 626: primitive "text-align #{ALIGN_TYPE_NAMES[alignment.to_i]}" 627: end
SVG-compatible version of text_align
# File lib/RMagick.rb, line 630 630: def text_anchor(anchor) 631: if ( not ANCHOR_TYPE_NAMES.has_key?(anchor.to_i) ) 632: Kernel.raise ArgumentError, "Unknown anchor constant: #{anchor}" 633: end 634: primitive "text-anchor #{ANCHOR_TYPE_NAMES[anchor.to_i]}" 635: end
Specify center of coordinate space to use for subsequent drawing commands.
# File lib/RMagick.rb, line 650 650: def translate(x, y) 651: primitive "translate #{x},#{y}" 652: end