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


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# File 'ext/RMagick/rmdraw.c', line 811

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.


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

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.

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# File 'ext/RMagick/rmdraw.c', line 479

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 = rm_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
#if defined(HAVE_INTERPRETIMAGEPROPERTIES)
    draw->info->text = InterpretImageProperties(NULL, image, StringValuePtr(text));
#else
    draw->info->text = InterpretImageAttributes(NULL, image, StringValuePtr(text));
#endif
    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.


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# File 'lib/RMagick.rb', line 216

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.


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# File 'lib/RMagick.rb', line 222

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


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# File 'lib/RMagick.rb', line 232

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.


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# File 'lib/RMagick.rb', line 237

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

#clip_rule(rule) ⇒ Object

Define the clipping rule.


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# File 'lib/RMagick.rb', line 242

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


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# File 'lib/RMagick.rb', line 250

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


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# File 'ext/RMagick/rmdraw.c', line 557

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


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# File 'lib/RMagick.rb', line 259

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.

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# File 'ext/RMagick/rmdraw.c', line 578

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_name;
    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 = rm_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_name = magick_malloc(sizeof(struct TmpFile_Name)+strlen(name));
    strcpy(tmpfile_name->name, name);
    tmpfile_name->next = draw->tmpfile_ary;
    draw->tmpfile_ary = tmpfile_name;

    // 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)


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# File 'lib/RMagick.rb', line 268

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”.


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

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

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# File 'ext/RMagick/rmdraw.c', line 703

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

    image_arg = rm_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


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# File 'ext/RMagick/rmdraw.c', line 736

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


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# File 'lib/RMagick.rb', line 295

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.


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

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


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# File 'lib/RMagick.rb', line 307

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

#fill_opacity(opacity) ⇒ Object

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


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# File 'lib/RMagick.rb', line 314

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

#fill_rule(rule) ⇒ Object


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# File 'lib/RMagick.rb', line 318

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


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# File 'lib/RMagick.rb', line 326

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

#font_family(name) ⇒ Object


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# File 'lib/RMagick.rb', line 330

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

#font_stretch(stretch) ⇒ Object


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# File 'lib/RMagick.rb', line 334

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


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

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]


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# File 'lib/RMagick.rb', line 350

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


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# File 'ext/RMagick/rmdraw.c', line 771

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.

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# File 'ext/RMagick/rmdraw.c', line 761

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


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# File 'lib/RMagick.rb', line 360

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


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# File 'ext/RMagick/rmdraw.c', line 785

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


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# File 'ext/RMagick/rmdraw.c', line 832

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


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

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


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# File 'lib/RMagick.rb', line 374

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.


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# File 'lib/RMagick.rb', line 383

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.


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

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


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# File 'lib/RMagick.rb', line 402

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.


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# File 'lib/RMagick.rb', line 416

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.


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# File 'lib/RMagick.rb', line 422

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

#polygon(*points) ⇒ Object

Draw a polygon


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# File 'lib/RMagick.rb', line 428

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


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# File 'lib/RMagick.rb', line 438

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')


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# File 'lib/RMagick.rb', line 453

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

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# File 'ext/RMagick/rmdraw.c', line 865

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')


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

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


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# File 'lib/RMagick.rb', line 477

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


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# File 'lib/RMagick.rb', line 483

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


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# File 'lib/RMagick.rb', line 488

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.


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# File 'lib/RMagick.rb', line 494

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

#skewx(angle) ⇒ Object


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# File 'lib/RMagick.rb', line 498

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

#skewy(angle) ⇒ Object


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# File 'lib/RMagick.rb', line 502

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.


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

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

#stroke_antialias(bool) ⇒ Object

Specify if stroke should be antialiased or not


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# File 'lib/RMagick.rb', line 514

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

#stroke_dasharray(*list) ⇒ Object

Specify a stroke dash pattern


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# File 'lib/RMagick.rb', line 520

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


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

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

#stroke_linecap(value) ⇒ Object


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

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


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# File 'lib/RMagick.rb', line 545

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


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# File 'lib/RMagick.rb', line 552

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)

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# File 'lib/RMagick.rb', line 561

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

#stroke_width(pixels) ⇒ Object

Specify stroke (outline) width in pixels.


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# File 'lib/RMagick.rb', line 566

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.


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# File 'lib/RMagick.rb', line 571

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


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

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


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# File 'lib/RMagick.rb', line 599

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.


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# File 'lib/RMagick.rb', line 607

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

#text_undercolor(color) ⇒ Object

Specify color underneath text


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# File 'lib/RMagick.rb', line 613

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.


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# File 'lib/RMagick.rb', line 619

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