Class: Magick::Draw

Inherits:
Object
  • Object
show all
Defined in:
lib/RMagick.rb,
ext/RMagick/rmmain.c

Constant Summary collapse

ALIGN_TYPE_NAMES =

Thse hashes are used to map Magick constant values to the strings used in the primitives.

{
LeftAlign.to_i => 'left',
RightAlign.to_i => 'right',
CenterAlign.to_i => 'center'
}.freeze
ANCHOR_TYPE_NAMES =
{
StartAnchor.to_i => 'start',
MiddleAnchor.to_i => 'middle',
EndAnchor.to_i => 'end'
}.freeze
DECORATION_TYPE_NAMES =
{
NoDecoration.to_i => 'none',
UnderlineDecoration.to_i => 'underline',
OverlineDecoration.to_i => 'overline',
LineThroughDecoration.to_i => 'line-through'
}.freeze
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'
}.freeze
PAINT_METHOD_NAMES =
{
PointMethod.to_i => 'point',
ReplaceMethod.to_i => 'replace',
FloodfillMethod.to_i => 'floodfill',
FillToBorderMethod.to_i => 'filltoborder',
ResetMethod.to_i => 'reset'
}.freeze
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'
}.freeze
STYLE_TYPE_NAMES =
{
NormalStyle.to_i => 'normal',
ItalicStyle.to_i => 'italic',
ObliqueStyle.to_i => 'oblique',
AnyStyle.to_i => 'all'
}.freeze

Instance Method Summary collapse

Constructor Details

#initializeObject

Method: Draw#initialize <{ info initializers }> Purpose: Initialize Draw object



786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
# File 'ext/RMagick/rmdraw.c', line 786

VALUE
Draw_initialize(VALUE self)
{
    Draw *draw, *draw_options;
    volatile VALUE options;

    Data_Get_Struct(self, Draw, draw);

    options = new_DrawOptions();
    Data_Get_Struct(options, Draw, draw_options);
    draw->info = draw_options->info;
    draw_options->info = NULL;

    return self;
}

Instance Method Details

#affine(sx, rx, ry, sy, tx, ty) ⇒ Object

Apply coordinate transformations to support scaling (s), rotation ®, and translation (t). Angles are specified in radians.



183
184
185
# File 'lib/RMagick.rb', line 183

def affine(sx, rx, ry, sy, tx, ty)
    primitive "affine " + sprintf("%g,%g,%g,%g,%g,%g", sx, rx, ry, sy, tx, ty)
end

#annotate(image_arg, width_arg, height_arg, x_arg, y_arg, text) ⇒ Object

Method: Draw#annotate(img, w, h, x, y, text) <parms> Purpose: annotates an image with text Returns: self Notes: Additional Draw attribute methods may be called in the

optional block, which is executed in the context of an
Draw object.


460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
# File 'ext/RMagick/rmdraw.c', line 460

VALUE Draw_annotate(
                   VALUE self,
                   VALUE image_arg,
                   VALUE width_arg,
                   VALUE height_arg,
                   VALUE x_arg,
                   VALUE y_arg,
                   VALUE text)
{
    Draw *draw;
    Image *image;
    unsigned long width, height;
    long x, y;
    AffineMatrix keep;
    char geometry_str[50];

    // Save the affine matrix in case it is modified by
    // Draw#rotation=
    Data_Get_Struct(self, Draw, draw);
    keep = draw->info->affine;

    image_arg = ImageList_cur_image(image_arg);
    image = rm_check_frozen(image_arg);

    // If we have an optional parm block, run it in self's context,
    // allowing the app a chance to modify the object's attributes
    if (rb_block_given_p())
    {
        (void)rb_obj_instance_eval(0, NULL, self);
    }

    // Translate & store in Draw structure
    draw->info->text = InterpretImageAttributes(NULL, image, StringValuePtr(text));
    if (!draw->info->text)
    {
        rb_raise(rb_eArgError, "no text");
    }

    // Create geometry string, copy to Draw structure, overriding
    // any previously existing value.
    width  = NUM2ULONG(width_arg);
    height = NUM2ULONG(height_arg);
    x      = NUM2LONG(x_arg);
    y      = NUM2LONG(y_arg);

    if (width == 0 && height == 0)
    {
        sprintf(geometry_str, "%+ld%+ld", x, y);
    }

    // WxH is non-zero
    else
    {
        sprintf(geometry_str, "%lux%lu%+ld%+ld", width, height, x, y);
    }

    magick_clone_string(&draw->info->geometry, geometry_str);

    (void) AnnotateImage(image, draw->info);

    magick_free(draw->info->text);
    draw->info->text = NULL;
    draw->info->affine = keep;

    rm_check_image_exception(image, RetainOnError);

    return self;
}

#arc(startX, startY, endX, endY, startDegrees, endDegrees) ⇒ Object

Draw an arc.



188
189
190
191
# File 'lib/RMagick.rb', line 188

def arc(startX, startY, endX, endY, startDegrees, endDegrees)
    primitive "arc " + sprintf("%g,%g %g,%g %g,%g",
                startX, startY, endX, endY, startDegrees, endDegrees)
end

#bezier(*points) ⇒ Object

Draw a bezier curve.



194
195
196
197
198
199
200
201
# File 'lib/RMagick.rb', line 194

def bezier(*points)
    if points.length == 0
        Kernel.raise ArgumentError, "no points specified"
    elsif points.length % 2 != 0
        Kernel.raise ArgumentError, "odd number of arguments specified"
    end
    primitive "bezier " + points.join(',')
end

#circle(originX, originY, perimX, perimY) ⇒ Object

Draw a circle



204
205
206
# File 'lib/RMagick.rb', line 204

def circle(originX, originY, perimX, perimY)
    primitive "circle " + sprintf("%g,%g %g,%g", originX, originY, perimX, perimY)
end

#clip_path(name) ⇒ Object

Invoke a clip-path defined by def_clip_path.



209
210
211
# File 'lib/RMagick.rb', line 209

def clip_path(name)
    primitive "clip-path #{name}"
end

#clip_rule(rule) ⇒ Object

Define the clipping rule.



214
215
216
217
218
219
# File 'lib/RMagick.rb', line 214

def clip_rule(rule)
    if ( not ["evenodd", "nonzero"].include?(rule.downcase) )
        Kernel.raise ArgumentError, "Unknown clipping rule #{rule}"
    end
    primitive "clip-rule #{rule}"
end

#clip_units(unit) ⇒ Object

Define the clip units



222
223
224
225
226
227
# File 'lib/RMagick.rb', line 222

def clip_units(unit)
    if ( not ["userspace", "userspaceonuse", "objectboundingbox"].include?(unit.downcase) )
        Kernel.raise ArgumentError, "Unknown clip unit #{unit}"
    end
    primitive "clip-units #{unit}"
end

#cloneObject

Method: Draw#clone Notes: see dup, init_copy



534
535
536
537
538
539
540
541
542
543
544
545
546
# File 'ext/RMagick/rmdraw.c', line 534

VALUE
Draw_clone(VALUE self)
{
    volatile VALUE clone;

    clone = Draw_dup(self);
    if (OBJ_FROZEN(self))
    {
        OBJ_FREEZE(clone);
    }

    return clone;
}

#color(x, y, method) ⇒ Object

Set color in image according to specified colorization rule. Rule is one of point, replace, floodfill, filltoborder,reset



231
232
233
234
235
236
# File 'lib/RMagick.rb', line 231

def color(x, y, method)
    if ( not PAINT_METHOD_NAMES.has_key?(method.to_i) )
        Kernel.raise ArgumentError, "Unknown PaintMethod: #{method}"
    end
    primitive "color #{x},#{y},#{PAINT_METHOD_NAMES[method.to_i]}"
end

#composite(*args) ⇒ Object

Method: Draw#composite(x,y,width,height,img,operator=OverCompositeOp) Purpose: Implement the “image” drawing primitive Notes: The “img” argument can be either an ImageList object

or an Image argument.


555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
# File 'ext/RMagick/rmdraw.c', line 555

VALUE
Draw_composite(int argc, VALUE *argv, VALUE self)
{
    Draw *draw;
    const char *op = "Over";
    double x, y, width, height;
    CompositeOperator cop = OverCompositeOp;
    volatile VALUE image;
    Image *comp_img;
    struct TmpFile_Name *tmpfile;
    char name[MaxTextExtent];
    // Buffer for "image" primitive
    char primitive[MaxTextExtent];

    if (argc < 5 || argc > 6)
    {
        rb_raise(rb_eArgError, "wrong number of arguments (%d for 5 or 6)", argc);
    }

    // Retrieve the image to composite
    image = ImageList_cur_image(argv[4]);
    (void) rm_check_destroyed(image);

    x = NUM2DBL(argv[0]);
    y = NUM2DBL(argv[1]);
    width  = NUM2DBL(argv[2]);
    height = NUM2DBL(argv[3]);

    // The default composition operator is "Over".
    if (argc == 6)
    {
        VALUE_TO_ENUM(argv[5], cop, CompositeOperator);

        switch (cop)
        {
            case AddCompositeOp:
                op = "Add";
                break;
            case AtopCompositeOp:
                op = "Atop";
                break;
            case BumpmapCompositeOp:
                op = "Bumpmap";
                break;
            case ClearCompositeOp:
                op = "Clear";
                break;
            case CopyBlueCompositeOp:
                op = "CopyBlue";
                break;
            case CopyGreenCompositeOp:
                op = "CopyGreen";
                break;
            case CopyOpacityCompositeOp:
                op = "CopyOpacity";
                break;
            case CopyRedCompositeOp:
                op = "CopyRed";
                break;
            case CopyCompositeOp:
                op = "Copy";
                break;
            case DifferenceCompositeOp:
                op = "Difference";
                break;
            case InCompositeOp:
                op = "In";
                break;
            case MinusCompositeOp:
                op = "Minus";
                break;
            case MultiplyCompositeOp:
                op = "Multiply";
                break;
            case OutCompositeOp:
                op = "Out";
                break;
            case OverCompositeOp:
                op = "Over";
                break;
            case PlusCompositeOp:
                op = "Plus";
                break;
            case SubtractCompositeOp:
                op = "Subtract";
                break;
            case XorCompositeOp:
                op = "Xor";
                break;
            default:
                rb_raise(rb_eArgError, "unknown composite operator (%d)", cop);
                break;
        }
    }

    Data_Get_Struct(self, Draw, draw);

    // Create a temp copy of the composite image
    Data_Get_Struct(image, Image, comp_img);
    rm_write_temp_image(comp_img, name);

    // Add the temp filename to the filename array.
    // Use Magick storage since we need to keep the list around
    // until destroy_Draw is called.
    tmpfile = magick_malloc(sizeof(struct TmpFile_Name)+strlen(name));
    strcpy(tmpfile->name, name);
    tmpfile->next = draw->tmpfile_ary;
    draw->tmpfile_ary = tmpfile;

    // Form the drawing primitive
    (void) sprintf(primitive, "image %s %g,%g,%g,%g '%s'", op, x, y, width, height, name);


    // Send "primitive" to self.
    (void) rb_funcall(self, rb_intern("primitive"), 1, rb_str_new2(primitive));

    return self;
}

#decorate(decoration) ⇒ Object

Specify EITHER the text decoration (none, underline, overline, line-through) OR the text solid background color (any color name or spec)



240
241
242
243
244
245
246
# File 'lib/RMagick.rb', line 240

def decorate(decoration)
    if ( DECORATION_TYPE_NAMES.has_key?(decoration.to_i) )
        primitive "decorate #{DECORATION_TYPE_NAMES[decoration.to_i]}"
    else
        primitive "decorate #{enquote(decoration)}"
    end
end

#define_clip_path(name) ⇒ Object

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”.



253
254
255
256
257
258
259
260
261
262
263
264
# File 'lib/RMagick.rb', line 253

def define_clip_path(name)
    begin
        push('defs')
        push('clip-path', name)
        push('graphic-context')
        yield
    ensure
        pop('graphic-context')
        pop('clip-path')
        pop('defs')
    end
end

#draw(image_arg) ⇒ Object

Method: Draw#draw(i) Purpose: Execute the stored drawing primitives on the current image

image


679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
# File 'ext/RMagick/rmdraw.c', line 679

VALUE
Draw_draw(VALUE self, VALUE image_arg)
{
    Draw *draw;
    Image *image;

    image_arg = ImageList_cur_image(image_arg);
    image = rm_check_frozen(image_arg);

    Data_Get_Struct(self, Draw, draw);
    if (draw->primitives == 0)
    {
        rb_raise(rb_eArgError, "nothing to draw");
    }

    // Point the DrawInfo structure at the current set of primitives.
    magick_clone_string(&(draw->info->primitive), StringValuePtr(draw->primitives));

    (void) DrawImage(image, draw->info);
    rm_check_image_exception(image, RetainOnError);

    magick_free(draw->info->primitive);
    draw->info->primitive = NULL;

    return self;
}

#dupObject

Methods: Draw#dup Purpose: Copy a Draw object Notes: Constructs a new Draw object, then calls initialize_copy



712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
# File 'ext/RMagick/rmdraw.c', line 712

VALUE
Draw_dup(VALUE self)
{
    Draw *draw;
    volatile VALUE dup;

    draw = ALLOC(Draw);
    memset(draw, 0, sizeof(Draw));
    dup = Data_Wrap_Struct(CLASS_OF(self), mark_Draw, destroy_Draw, draw);
    if (rb_obj_tainted(self))
    {
        (void)rb_obj_taint(dup);
    }
    return rb_funcall(dup, rm_ID_initialize_copy, 1, self);
}

#ellipse(originX, originY, width, height, arcStart, arcEnd) ⇒ Object

Draw an ellipse



267
268
269
270
# File 'lib/RMagick.rb', line 267

def ellipse(originX, originY, width, height, arcStart, arcEnd)
    primitive "ellipse " + sprintf("%g,%g %g,%g %g,%g",
                    originX, originY, width, height, arcStart, arcEnd)
end

#encoding(encoding) ⇒ Object

Let anything through, but the only defined argument is “UTF-8”. All others are apparently ignored.



274
275
276
# File 'lib/RMagick.rb', line 274

def encoding(encoding)
    primitive "encoding #{encoding}"
end

#fill(colorspec) ⇒ Object Also known as: fill_color, fill_pattern

Specify object fill, a color name or pattern name



279
280
281
# File 'lib/RMagick.rb', line 279

def fill(colorspec)
    primitive "fill #{enquote(colorspec)}"
end

#fill_opacity(opacity) ⇒ Object

Specify fill opacity (use “xx%” to indicate percentage)



286
287
288
# File 'lib/RMagick.rb', line 286

def fill_opacity(opacity)
    primitive "fill-opacity #{opacity}"
end

#fill_rule(rule) ⇒ Object



290
291
292
293
294
295
# File 'lib/RMagick.rb', line 290

def fill_rule(rule)
    if ( not ["evenodd", "nonzero"].include?(rule.downcase) )
        Kernel.raise ArgumentError, "Unknown fill rule #{rule}"
    end
    primitive "fill-rule #{rule}"
end

#font(name) ⇒ Object

Specify text drawing font



298
299
300
# File 'lib/RMagick.rb', line 298

def font(name)
    primitive "font #{name}"
end

#font_family(name) ⇒ Object



302
303
304
# File 'lib/RMagick.rb', line 302

def font_family(name)
    primitive "font-family \'#{name}\'"
end

#font_stretch(stretch) ⇒ Object



306
307
308
309
310
311
# File 'lib/RMagick.rb', line 306

def font_stretch(stretch)
    if ( not STRETCH_TYPE_NAMES.has_key?(stretch.to_i) )
        Kernel.raise ArgumentError, "Unknown stretch type"
    end
    primitive "font-stretch #{STRETCH_TYPE_NAMES[stretch.to_i]}"
end

#font_style(style) ⇒ Object



313
314
315
316
317
318
# File 'lib/RMagick.rb', line 313

def font_style(style)
    if ( not STYLE_TYPE_NAMES.has_key?(style.to_i) )
        Kernel.raise ArgumentError, "Unknown style type"
    end
    primitive "font-style #{STYLE_TYPE_NAMES[style.to_i]}"
end

#font_weight(weight) ⇒ Object

The font weight argument can be either a font weight constant or [100,200,…,900]



322
323
324
325
326
327
328
# File 'lib/RMagick.rb', line 322

def font_weight(weight)
    if ( FONT_WEIGHT_NAMES.has_key?(weight.to_i) )
        primitive "font-weight #{FONT_WEIGHT_NAMES[weight.to_i]}"
    else
        primitive "font-weight #{weight}"
    end
end

#get_multiline_type_metrics(*args) ⇒ Object



747
748
749
750
751
752
753
754
# File 'ext/RMagick/rmdraw.c', line 747

VALUE
Draw_get_multiline_type_metrics(
                               int argc,
                               VALUE *argv,
                               VALUE self)
{
    return get_type_metrics(argc, argv, self, GetMultilineTypeMetrics);
}

#get_type_metrics(*args) ⇒ Object

Method: Draw#get_type_metrics([image, ]text)

Draw#get_multiline_type_metrics([image, ]text)

Purpose: returns measurements for a given font and text string Notes: If the image argument has been omitted, use a dummy

image, but make sure the text has none of the special
characters that refer to image attributes.


737
738
739
740
741
742
743
744
# File 'ext/RMagick/rmdraw.c', line 737

VALUE
Draw_get_type_metrics(
                     int argc,
                     VALUE *argv,
                     VALUE self)
{
    return get_type_metrics(argc, argv, self, GetTypeMetrics);
}

#gravity(grav) ⇒ Object

Specify the text positioning gravity, one of: NorthWest, North, NorthEast, West, Center, East, SouthWest, South, SouthEast



332
333
334
335
336
337
# File 'lib/RMagick.rb', line 332

def gravity(grav)
    if ( not GRAVITY_NAMES.has_key?(grav.to_i) )
        Kernel.raise ArgumentError, "Unknown text positioning gravity"
    end
    primitive "gravity #{GRAVITY_NAMES[grav.to_i]}"
end

#initialize_copy(orig) ⇒ Object

Method: Draw#initialize_copy Purpose: initialize clone, dup methods



760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
# File 'ext/RMagick/rmdraw.c', line 760

VALUE Draw_init_copy(VALUE self, VALUE orig)
{
    Draw *copy, *original;

    Data_Get_Struct(orig, Draw, original);
    Data_Get_Struct(self, Draw, copy);

    copy->info = CloneDrawInfo(NULL, original->info);
    if (!copy->info)
    {
        rb_raise(rb_eNoMemError, "not enough memory to continue");
    }

    if (original->primitives)
    {
        copy->primitives = rb_str_dup(original->primitives);
    }

    return self;
}

#inspectObject

Method: inspect Purpose: display the primitives



806
807
808
809
810
811
812
813
# File 'ext/RMagick/rmdraw.c', line 806

VALUE
Draw_inspect(VALUE self)
{
    Draw *draw;

    Data_Get_Struct(self, Draw, draw);
    return draw->primitives ? draw->primitives : rb_str_new2("(no primitives defined)");
}

#line(startX, startY, endX, endY) ⇒ Object

Draw a line



340
341
342
# File 'lib/RMagick.rb', line 340

def line(startX, startY, endX, endY)
    primitive "line " + sprintf("%g,%g %g,%g", startX, startY, endX, endY)
end

#matte(x, y, method) ⇒ Object

Set matte (make transparent) in image according to the specified colorization rule



346
347
348
349
350
351
# File 'lib/RMagick.rb', line 346

def matte(x, y, method)
    if ( not PAINT_METHOD_NAMES.has_key?(method.to_i) )
        Kernel.raise ArgumentError, "Unknown paint method"
    end
    primitive "matte #{x},#{y} #{PAINT_METHOD_NAMES[method.to_i]}"
end

#opacity(opacity) ⇒ Object

Specify drawing fill and stroke opacities. If the value is a string ending with a %, the number will be multiplied by 0.01.



355
356
357
358
359
360
361
362
# File 'lib/RMagick.rb', line 355

def opacity(opacity)
    if (Numeric === opacity)
        if (opacity < 0 || opacity > 1.0)
            Kernel.raise ArgumentError, "opacity must be >= 0 and <= 1.0"
        end
    end
    primitive "opacity #{opacity}"
end

#path(cmds) ⇒ Object

Draw using SVG-compatible path drawing commands. Note that the primitive requires that the commands be surrounded by quotes or apostrophes. Here we simply use apostrophes.



367
368
369
# File 'lib/RMagick.rb', line 367

def path(cmds)
    primitive "path '" + cmds + "'"
end

#pattern(name, x, y, width, height) ⇒ Object

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



374
375
376
377
378
379
380
381
382
383
384
385
# File 'lib/RMagick.rb', line 374

def pattern(name, x, y, width, height)
    begin
        push('defs')
        push("pattern #{name} #{x} #{y} #{width} #{height}")
        push('graphic-context')
        yield
    ensure
        pop('graphic-context')
        pop('pattern')
        pop('defs')
    end
end

#point(x, y) ⇒ Object

Set point to fill color.



388
389
390
# File 'lib/RMagick.rb', line 388

def point(x, y)
    primitive "point #{x},#{y}"
end

#pointsize(points) ⇒ Object Also known as: font_size

Specify the font size in points. Yes, the primitive is “font-size” but in other places this value is called the “pointsize”. Give it both names.



394
395
396
# File 'lib/RMagick.rb', line 394

def pointsize(points)
    primitive "font-size #{points}"
end

#polygon(*points) ⇒ Object

Draw a polygon



400
401
402
403
404
405
406
407
# File 'lib/RMagick.rb', line 400

def polygon(*points)
    if points.length == 0
        Kernel.raise ArgumentError, "no points specified"
    elsif points.length % 2 != 0
        Kernel.raise ArgumentError, "odd number of points specified"
    end
    primitive "polygon " + points.join(',')
end

#polyline(*points) ⇒ Object

Draw a polyline



410
411
412
413
414
415
416
417
# File 'lib/RMagick.rb', line 410

def polyline(*points)
    if points.length == 0
        Kernel.raise ArgumentError, "no points specified"
    elsif points.length % 2 != 0
        Kernel.raise ArgumentError, "odd number of points specified"
    end
    primitive "polyline " + points.join(',')
end

#pop(*what) ⇒ Object

Return to the previously-saved set of whatever pop(‘graphic-context’) (the default if no arguments) pop(‘defs’) pop(‘gradient’) pop(‘pattern’)



425
426
427
428
429
430
431
432
# File 'lib/RMagick.rb', line 425

def pop(*what)
    if what.length == 0
        primitive "pop graphic-context"
    else
        # to_s allows a Symbol to be used instead of a String
        primitive "pop " + what.map {|w| w.to_s}.join(' ')
    end
end

#primitive(primitive) ⇒ Object

Method: Draw#primitive Purpose: Add a drawing primitive to the list of primitives in the

Draw object


838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
# File 'ext/RMagick/rmdraw.c', line 838

VALUE
Draw_primitive(VALUE self, VALUE primitive)
{
    Draw *draw;

    rb_check_frozen(self);
    Data_Get_Struct(self, Draw, draw);

    if (draw->primitives == (VALUE)0)
    {
        draw->primitives = primitive;
    }
    else
    {
        draw->primitives = rb_str_concat(draw->primitives, rb_str_new2("\n"));
        draw->primitives = rb_str_concat(draw->primitives, primitive);
    }

    return self;
}

#push(*what) ⇒ Object

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’)



439
440
441
442
443
444
445
446
# File 'lib/RMagick.rb', line 439

def push(*what)
    if what.length == 0
        primitive "push graphic-context"
    else
        # to_s allows a Symbol to be used instead of a String
        primitive "push " + what.map {|w| w.to_s}.join(' ')
    end
end

#rectangle(upper_left_x, upper_left_y, lower_right_x, lower_right_y) ⇒ Object

Draw a rectangle



449
450
451
452
# File 'lib/RMagick.rb', line 449

def rectangle(upper_left_x, upper_left_y, lower_right_x, lower_right_y)
    primitive "rectangle " + sprintf("%g,%g %g,%g",
            upper_left_x, upper_left_y, lower_right_x, lower_right_y)
end

#rotate(angle) ⇒ Object

Specify coordinate space rotation. “angle” is measured in degrees



455
456
457
# File 'lib/RMagick.rb', line 455

def rotate(angle)
    primitive "rotate #{angle}"
end

#roundrectangle(center_x, center_y, width, height, corner_width, corner_height) ⇒ Object

Draw a rectangle with rounded corners



460
461
462
463
# File 'lib/RMagick.rb', line 460

def roundrectangle(center_x, center_y, width, height, corner_width, corner_height)
    primitive "roundrectangle " + sprintf("%g,%g,%g,%g,%g,%g",
        center_x, center_y, width, height, corner_width, corner_height)
end

#scale(x, y) ⇒ Object

Specify scaling to be applied to coordinate space on subsequent drawing commands.



466
467
468
# File 'lib/RMagick.rb', line 466

def scale(x, y)
    primitive "scale #{x},#{y}"
end

#skewx(angle) ⇒ Object



470
471
472
# File 'lib/RMagick.rb', line 470

def skewx(angle)
    primitive "skewX #{angle}"
end

#skewy(angle) ⇒ Object



474
475
476
# File 'lib/RMagick.rb', line 474

def skewy(angle)
    primitive "skewY #{angle}"
end

#stroke(colorspec) ⇒ Object Also known as: stroke_color, stroke_pattern

Specify the object stroke, a color name or pattern name.



479
480
481
# File 'lib/RMagick.rb', line 479

def stroke(colorspec)
    primitive "stroke #{enquote(colorspec)}"
end

#stroke_antialias(bool) ⇒ Object

Specify if stroke should be antialiased or not



486
487
488
489
# File 'lib/RMagick.rb', line 486

def stroke_antialias(bool)
    bool = bool ? '1' : '0'
    primitive "stroke-antialias #{bool}"
end

#stroke_dasharray(*list) ⇒ Object

Specify a stroke dash pattern



492
493
494
495
496
497
498
499
500
501
502
503
# File 'lib/RMagick.rb', line 492

def stroke_dasharray(*list)
    if list.length == 0
        primitive "stroke-dasharray none"
    else
        list.each { |x|
            if x <= 0 then
                Kernel.raise ArgumentError, "dash array elements must be > 0 (#{x} given)"
            end
        }
        primitive "stroke-dasharray #{list.join(',')}"
    end
end

#stroke_dashoffset(value = 0) ⇒ Object

Specify the initial offset in the dash pattern



506
507
508
# File 'lib/RMagick.rb', line 506

def stroke_dashoffset(value=0)
    primitive "stroke-dashoffset #{value}"
end

#stroke_linecap(value) ⇒ Object



510
511
512
513
514
515
# File 'lib/RMagick.rb', line 510

def stroke_linecap(value)
    if ( not ["butt", "round", "square"].include?(value.downcase) )
        Kernel.raise ArgumentError, "Unknown linecap type: #{value}"
    end
    primitive "stroke-linecap #{value}"
end

#stroke_linejoin(value) ⇒ Object



517
518
519
520
521
522
# File 'lib/RMagick.rb', line 517

def stroke_linejoin(value)
    if ( not ["round", "miter", "bevel"].include?(value.downcase) )
        Kernel.raise ArgumentError, "Unknown linejoin type: #{value}"
    end
    primitive "stroke-linejoin #{value}"
end

#stroke_miterlimit(value) ⇒ Object



524
525
526
527
528
529
# File 'lib/RMagick.rb', line 524

def stroke_miterlimit(value)
    if (value < 1)
        Kernel.raise ArgumentError, "miterlimit must be >= 1"
    end
    primitive "stroke-miterlimit #{value}"
end

#stroke_opacity(value) ⇒ Object

Specify opacity of stroke drawing color

(use "xx%" to indicate percentage)


533
534
535
# File 'lib/RMagick.rb', line 533

def stroke_opacity(value)
    primitive "stroke-opacity #{value}"
end

#stroke_width(pixels) ⇒ Object

Specify stroke (outline) width in pixels.



538
539
540
# File 'lib/RMagick.rb', line 538

def stroke_width(pixels)
    primitive "stroke-width #{pixels}"
end

#text(x, y, text) ⇒ Object

Draw text at position x,y. Add quotes to text that is not already quoted.



543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
# File 'lib/RMagick.rb', line 543

def text(x, y, text)
    if text.to_s.empty?
        Kernel.raise ArgumentError, "missing text argument"
    end
    if text.length > 2 && /\A(?:\"[^\"]+\"|\'[^\']+\'|\{[^\}]+\})\z/.match(text)
        ; # text already quoted
    elsif !text['\'']
        text = '\''+text+'\''
    elsif !text['"']
        text = '"'+text+'"'
    elsif !(text['{'] || text['}'])
        text = '{'+text+'}'
    else
        # escape existing braces, surround with braces
        text = '{' +  text.gsub(/[}]/) { |b| '\\' + b } + '}'
    end
    primitive "text #{x},#{y} #{text}"
end

#text_align(alignment) ⇒ Object

Specify text alignment relative to a given point



563
564
565
566
567
568
# File 'lib/RMagick.rb', line 563

def text_align(alignment)
    if ( not ALIGN_TYPE_NAMES.has_key?(alignment.to_i) )
        Kernel.raise ArgumentError, "Unknown alignment constant: #{alignment}"
    end
    primitive "text-align #{ALIGN_TYPE_NAMES[alignment.to_i]}"
end

#text_anchor(anchor) ⇒ Object

SVG-compatible version of text_align



571
572
573
574
575
576
# File 'lib/RMagick.rb', line 571

def text_anchor(anchor)
    if ( not ANCHOR_TYPE_NAMES.has_key?(anchor.to_i) )
        Kernel.raise ArgumentError, "Unknown anchor constant: #{anchor}"
    end
    primitive "text-anchor #{ANCHOR_TYPE_NAMES[anchor.to_i]}"
end

#text_antialias(boolean) ⇒ Object

Specify if rendered text is to be antialiased.



579
580
581
582
# File 'lib/RMagick.rb', line 579

def text_antialias(boolean)
    boolean = boolean ? '1' : '0'
    primitive "text-antialias #{boolean}"
end

#text_undercolor(color) ⇒ Object

Specify color underneath text



585
586
587
# File 'lib/RMagick.rb', line 585

def text_undercolor(color)
    primitive "text-undercolor #{enquote(color)}"
end

#translate(x, y) ⇒ Object

Specify center of coordinate space to use for subsequent drawing commands.



591
592
593
# File 'lib/RMagick.rb', line 591

def translate(x, y)
    primitive "translate #{x},#{y}"
end