Class: Magick::Pixel

Inherits:
Object
  • Object
show all
Includes:
Comparable
Defined in:
ext/RMagick/rmmain.c

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*args) ⇒ Object

Ruby usage:

- @verbatim Pixel#initialize @endverbatim
- @verbatim Pixel#initialize(red) @endverbatim
- @verbatim Pixel#initialize(red,green) @endverbatim
- @verbatim Pixel#initialize(red,green,blue) @endverbatim
- @verbatim Pixel#initialize(red,green,blue,opacity) @endverbatim

Notes:

- Default red is 0.0
- Default green is 0.0
- Default blue is 0.0
- Default opacity is 0.0
- For backward compatibility, arguments may be nil.

Parameters:

  • argc —

    number of input arguments

  • argv —

    array of input arguments

  • self —

    this object



766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
 
# File 'ext/RMagick/rmpixel.c', line 766

VALUE
Pixel_initialize(int argc, VALUE *argv, VALUE self)
{
    Pixel *pixel;

    Data_Get_Struct(self, Pixel, pixel);

    switch(argc)
    {
        case 4:
            if (argv[3] != Qnil)
            {
                pixel->opacity = APP2QUANTUM(argv[3]);
            }
        case 3:
            if (argv[2] != Qnil)
            {
                pixel->blue = APP2QUANTUM(argv[2]);
            }
        case 2:
            if (argv[1] != Qnil)
            {
                pixel->green = APP2QUANTUM(argv[1]);
            }
        case 1:
            if (argv[0] != Qnil)
            {
                pixel->red = APP2QUANTUM(argv[0]);
            }
        case 0:
            break;
        default:
            rb_raise(rb_eArgError, "wrong number of arguments (%d for 0 to 4)", argc);
    }

    return self;
}

Class Method Details

.from_color(name) ⇒ Object

Construct an Magick::Pixel corresponding to the given color name.

Ruby usage:

- @verbatim Magick::Pixel.from_color(string) @endverbatim

Notes:

- The "inverse" is Image_to_color, b/c the conversion of a pixel to a
  color name requires both a color depth and if the opacity value has
  meaning (i.e. whether image->matte == True or not).

Parameters:

  • class —

    the Ruby class to use

  • name —

    the color name

Returns:

  • a new Magic::Pixel object

See Also:

  • Image_to_color
  • Pixel_to_color


510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
 
# File 'ext/RMagick/rmpixel.c', line 510

VALUE
Pixel_from_color(VALUE class ATTRIBUTE_UNUSED, VALUE name)
{
    PixelColor pp;
    ExceptionInfo *exception;
    MagickBooleanType okay;

    exception = AcquireExceptionInfo();
    okay = QueryColorCompliance(StringValuePtr(name), AllCompliance, &pp, exception);
    CHECK_EXCEPTION()
    (void) DestroyExceptionInfo(exception);

    if (!okay)
    {
        rb_raise(rb_eArgError, "invalid color name: %s", StringValuePtr(name));
    }

    return Pixel_from_PixelColor(&pp);
}

.from_hsla(*args) ⇒ Object

Construct an RGB pixel.

Ruby usage:

- @verbatim Pixel#from_hsla(hue, saturation, lightness) @endverbatim
- @verbatim Pixel#from_hsla(hue, saturation, lightness, alpha) @endverbatim

Notes:

- Default alpha is 1.0
- 0 <= hue < 360 OR "0%" <= hue < "100%"
- 0 <= saturation <= 255 OR "0%" <= saturation <= "100%"
- 0 <= lightness <= 255 OR "0%" <= lightness <= "100%"
- 0 <= alpha <= 1 (0 is transparent, 1 is opaque) OR "0%" <= alpha <= "100%"

Parameters:

  • argc —

    number of input arguments

  • argv —

    array of input arguments

  • class —

    the Ruby class to use

Returns:

  • a new Magick::Pixel object



550
551
552
553
554
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
 
# File 'ext/RMagick/rmpixel.c', line 550

VALUE
Pixel_from_hsla(int argc, VALUE *argv, VALUE class ATTRIBUTE_UNUSED)
{
    double h, s, l, a = 1.0;
    MagickPixel pp;
    ExceptionInfo *exception;
    char name[50];
    MagickBooleanType alpha = MagickFalse;

    switch (argc)
    {
        case 4:
            a = rm_percentage(argv[3],1.0);
            alpha = MagickTrue;
        case 3:
            // saturation and lightness are out of 255 in new ImageMagicks and
            // out of 100 in old ImageMagicks. Compromise: always use %.
            l = rm_percentage(argv[2],255.0);
            s = rm_percentage(argv[1],255.0);
            h = rm_percentage(argv[0],360.0);
            break;
        default:
            rb_raise(rb_eArgError, "wrong number of arguments (%d for 3 or 4)", argc);
            break;
    }

    if (alpha && (a < 0.0 || a > 1.0))
    {
        rb_raise(rb_eRangeError, "alpha %g out of range [0.0, 1.0]", a);
    }
    if (l < 0.0 || l > 255.0)
    {
        rb_raise(rb_eRangeError, "lightness %g out of range [0.0, 255.0]", l);
    }
    if (s < 0.0 || s > 255.0)
    {
        rb_raise(rb_eRangeError, "saturation %g out of range [0.0, 255.0]", s);
    }
    if (h < 0.0 || h >= 360.0)
    {
        rb_raise(rb_eRangeError, "hue %g out of range [0.0, 360.0)", h);
    }

    memset(name, 0, sizeof(name));
    if (alpha)
    {
        sprintf(name, "hsla(%-2.1f,%-2.1f,%-2.1f,%-2.1f)", h, s, l, a);
    }
    else
    {
        sprintf(name, "hsl(%-2.1f,%-2.1f,%-2.1f)", h, s, l);
    }

    exception = AcquireExceptionInfo();

    (void) QueryMagickColor(name, &pp, exception);
    CHECK_EXCEPTION()

    (void) DestroyExceptionInfo(exception);

    return Pixel_from_MagickPixel(&pp);
}

Instance Method Details

#<=>(other) ⇒ Object

Support Comparable mixin.

Ruby usage:

- @verbatim Pixel#<=> @endverbatim

Parameters:

  • self —

    this object

  • other —

    the other Pixel

Returns:

  • -1, 0, 1



892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
 
# File 'ext/RMagick/rmpixel.c', line 892

VALUE
Pixel_spaceship(VALUE self, VALUE other)
{
    Pixel *this, *that;

    Data_Get_Struct(self, Pixel, this);
    Data_Get_Struct(other, Pixel, that);

    if (this->red != that->red)
    {
        return INT2NUM((this->red - that->red)/abs(this->red - that->red));
    }
    else if(this->green != that->green)
    {
        return INT2NUM((this->green - that->green)/abs(this->green - that->green));
    }
    else if(this->blue != that->blue)
    {
        return INT2NUM((this->blue - that->blue)/abs(this->blue - that->blue));
    }
    else if(this->opacity != that->opacity)
    {
        return INT2NUM(((QuantumRange - this->opacity) - (QuantumRange - that->opacity))/abs((QuantumRange - this->opacity) - (QuantumRange - that->opacity)));
    }

    // Values are equal, check class.

    return rb_funcall(CLASS_OF(self), rb_intern("<=>"), 1, CLASS_OF(other));

}

#===(other) ⇒ Object

“Case equal” operator for Pixel.

Ruby usage:

- @verbatim Pixel#=== @endverbatim

Parameters:

  • self —

    this object

  • other —

    the other object

Returns:

  • true or false



327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
 
# File 'ext/RMagick/rmpixel.c', line 327

VALUE
Pixel_case_eq(VALUE self, VALUE other)
{
    Pixel *this, *that;

    if (CLASS_OF(self) == CLASS_OF(other))
    {
        Data_Get_Struct(self, Pixel, this);
        Data_Get_Struct(other, Pixel, that);
        return (this->red == that->red
            && this->blue == that->blue
            && this->green == that->green
            && this->opacity == that->opacity) ? Qtrue : Qfalse;
    }

    return Qfalse;
}

#clone ⇒ Object

Clone a Pixel.

Ruby usage:

- @verbatim Pixel#clone @endverbatim

Parameters:

  • self —

    this object

Returns:

  • a clone

See Also:

  • Pixel_dup
  • Pixel_init_copy


357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
 
# File 'ext/RMagick/rmpixel.c', line 357

VALUE
Pixel_clone(VALUE self)
{
    VALUE clone;

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

    RB_GC_GUARD(clone);

    return clone;
}

#dup ⇒ Object

Duplicate a Pixel.

Ruby usage:

- @verbatim Pixel#dup @endverbatim

Parameters:

  • self —

    this object

Returns:

  • a clone

See Also:

  • Pixel_clone
  • Pixel_init_copy


385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
 
# File 'ext/RMagick/rmpixel.c', line 385

VALUE
Pixel_dup(VALUE self)
{
    Pixel *pixel;
    VALUE dup;

    pixel = ALLOC(Pixel);
    memset(pixel, '\0', sizeof(Pixel));
    dup = Data_Wrap_Struct(CLASS_OF(self), NULL, destroy_Pixel, pixel);
    if (rb_obj_tainted(self))
    {
        (void) rb_obj_taint(dup);
    }

    RB_GC_GUARD(dup);

    return rb_funcall(dup, rm_ID_initialize_copy, 1, self);
}

#eql?(other) ⇒ Boolean

For use with Hash.

Ruby usage:

- @verbatim Pixel#eql? @endverbatim

Parameters:

  • self —

    this object

  • other —

    the other object

Returns:

  • (Boolean) —

    true if hash to the same value, otherwise false



415
416
417
418
419
 
# File 'ext/RMagick/rmpixel.c', line 415

VALUE
Pixel_eql_q(VALUE self, VALUE other)
{
    return NUM2INT(Pixel_spaceship(self, other)) == 0 ? Qtrue : Qfalse;
}

#fcmp(*args) ⇒ Object

Compare pixel values for equality.

Ruby usage:

- @verbatim Pixel#fcmp(other, fuzz, colorspace) @endverbatim

Notes:

- Default fuzz is 0.0
- Default colorspace is RGBColorspace

Parameters:

  • argc —

    number of input arguments

  • argv —

    array of input arguments

  • self —

    this object

Returns:

  • true if equal, otherwise false



437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
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
 
# File 'ext/RMagick/rmpixel.c', line 437

VALUE
Pixel_fcmp(int argc, VALUE *argv, VALUE self)
{
    double fuzz = 0.0;
    unsigned int equal;
    ColorspaceType colorspace = RGBColorspace;
    Image *image;
    Info *info;
    Pixel *this, *that;

    switch (argc)
    {
        case 3:
            VALUE_TO_ENUM(argv[2], colorspace, ColorspaceType);
        case 2:
            fuzz = NUM2DBL(argv[1]);
        case 1:
            // Allow 1 argument
            break;
        default:
            rb_raise(rb_eArgError, "wrong number of arguments (%d for 1 to 3)", argc);
            break;
    }

    Data_Get_Struct(self, Pixel, this);
    Data_Get_Struct(argv[0], Pixel, that);

    // The IsColorSimilar function expects to get the
    // colorspace and fuzz parameters from an Image structure.

    info = CloneImageInfo(NULL);
    if (!info)
    {
        rb_raise(rb_eNoMemError, "not enough memory to continue");
    }

    image = rm_acquire_image(info);

    // Delete Info now in case we have to raise an exception
    (void) DestroyImageInfo(info);

    if (!image)
    {
        rb_raise(rb_eNoMemError, "not enough memory to continue");
    }

    image->colorspace = colorspace;
    image->fuzz = fuzz;

    equal = IsColorSimilar(image, this, that);
    (void) DestroyImage(image);

    return equal ? Qtrue : Qfalse;
}

#hash ⇒ Object

Ruby usage:

- @verbatim Pixel#hash @endverbatim

Notes:

- INT2FIX left-shifts 1 bit. Sacrifice 1 bit from the opacity attribute to
  the FIXNUM_FLAG.

Parameters:

  • self —

    this object

Returns:

  • the hash of self



703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
 
# File 'ext/RMagick/rmpixel.c', line 703

VALUE
Pixel_hash(VALUE self)
{
    Pixel *pixel;
    unsigned int hash;

    Data_Get_Struct(self, Pixel, pixel);

    hash  = ScaleQuantumToChar(pixel->red)   << 24;
    hash += ScaleQuantumToChar(pixel->green) << 16;
    hash += ScaleQuantumToChar(pixel->blue)  << 8;
    hash += ScaleQuantumToChar(QuantumRange - pixel->opacity);

    return UINT2NUM(hash >> 1);
}

#initialize_copy(orig) ⇒ Object

Initialize clone, dup methods.

Ruby usage:

- @verbatim Pixel#initialize_copy @endverbatim

Parameters:

  • self —

    this object

  • orig —

    the original Pixel

Returns:

  • self

See Also:

  • Pixel_clone
  • Pixel_dup


732
733
734
735
736
737
738
739
740
741
742
743
 
# File 'ext/RMagick/rmpixel.c', line 732

VALUE
Pixel_init_copy(VALUE self, VALUE orig)
{
    Pixel *copy, *original;

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

    *copy = *original;

    return self;
}

#intensity ⇒ Object

Return the “intensity” of a pixel.

Ruby usage:

- @verbatim Pixel#intensity @endverbatim

Parameters:

  • self —

    this object

Returns:

  • the intensity



814
815
816
817
818
819
820
821
822
823
824
825
826
827
 
# File 'ext/RMagick/rmpixel.c', line 814

VALUE
Pixel_intensity(VALUE self)
{
    Pixel *pixel;
    Quantum intensity;

    Data_Get_Struct(self, Pixel, pixel);

    intensity = ROUND_TO_QUANTUM((0.299*pixel->red)
                                + (0.587*pixel->green)
                                + (0.114*pixel->blue));

    return QUANTUM2NUM((unsigned long) intensity);
}

#marshal_dump ⇒ Object

Support Marshal.dump.

Ruby usage:

- @verbatim Pixel#marshal_dump @endverbatim

Parameters:

  • self —

    this object

Returns:

  • a string representing the dumped pixel



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

VALUE
Pixel_marshal_dump(VALUE self)
{
    Pixel *pixel;
    VALUE dpixel;

    Data_Get_Struct(self, Pixel, pixel);
    dpixel = rb_hash_new();
    rb_hash_aset(dpixel, CSTR2SYM("red"), QUANTUM2NUM(pixel->red));
    rb_hash_aset(dpixel, CSTR2SYM("green"), QUANTUM2NUM(pixel->green));
    rb_hash_aset(dpixel, CSTR2SYM("blue"), QUANTUM2NUM(pixel->blue));
    rb_hash_aset(dpixel, CSTR2SYM("opacity"), QUANTUM2NUM(pixel->opacity));

    RB_GC_GUARD(dpixel);

    return dpixel;
}

#marshal_load(dpixel) ⇒ Object

Support Marshal.load.

Ruby usage:

- @verbatim Pixel#marshal_load @endverbatim

Parameters:

  • self —

    this object

  • dpixel —

    the dumped pixel

Returns:

  • self



868
869
870
871
872
873
874
875
876
877
878
879
 
# File 'ext/RMagick/rmpixel.c', line 868

VALUE
Pixel_marshal_load(VALUE self, VALUE dpixel)
{
    Pixel *pixel;

    Data_Get_Struct(self, Pixel, pixel);
    pixel->red = NUM2QUANTUM(rb_hash_aref(dpixel, CSTR2SYM("red")));
    pixel->green = NUM2QUANTUM(rb_hash_aref(dpixel, CSTR2SYM("green")));
    pixel->blue = NUM2QUANTUM(rb_hash_aref(dpixel, CSTR2SYM("blue")));
    pixel->opacity = NUM2QUANTUM(rb_hash_aref(dpixel, CSTR2SYM("opacity")));
    return self;
}

#to_color(*args) ⇒ Object

Return the color name corresponding to the pixel values.

Ruby usage:

- @verbatim Magick::Pixel#to_color @endverbatim
- @verbatim Magick::Pixel#to_color(compliance) @endverbatim
- @verbatim Magick::Pixel#to_color(compliance, matte) @endverbatim
- @verbatim Magick::Pixel#to_color(compliance, matte, depth) @endverbatim
- @verbatim Magick::Pixel#to_color(compliance, matte, depth, hex) @endverbatim

Notes:

- Default compliance is AllCompliance
- Default matte is false
- Default depth is MAGICKCORE_QUANTUM_DEPTH
- Default hex is false
- The conversion respects the value of the 'opacity' field in the Pixel

Parameters:

  • argc —

    number of input arguments

  • argv —

    array of input arguments

  • self —

    this object

Returns:

  • the color name as a String



1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
 
# File 'ext/RMagick/rmpixel.c', line 1015

VALUE
Pixel_to_color(int argc, VALUE *argv, VALUE self)
{
    Info *info;
    Image *image;
    Pixel *pixel;
    MagickPixel mpp;
    MagickBooleanType hex = MagickFalse;
    char name[MaxTextExtent];
    ExceptionInfo *exception;
    ComplianceType compliance = AllCompliance;
    unsigned int matte = MagickFalse;
    unsigned int depth = MAGICKCORE_QUANTUM_DEPTH;

    switch (argc)
    {
        case 4:
            hex = RTEST(argv[3]);
        case 3:
            depth = NUM2UINT(argv[2]);

            // Ensure depth is appropriate for the way xMagick was compiled.
            switch (depth)
            {
                case 8:
#if MAGICKCORE_QUANTUM_DEPTH == 16 || MAGICKCORE_QUANTUM_DEPTH == 32
                case 16:
#endif
#if MAGICKCORE_QUANTUM_DEPTH == 32
                case 32:
#endif
                    break;
                default:
                    rb_raise(rb_eArgError, "invalid depth (%d)", depth);
                    break;
            }
       case 2:
            matte = RTEST(argv[1]);
        case 1:
            VALUE_TO_ENUM(argv[0], compliance, ComplianceType);
        case 0:
            break;
        default:
            rb_raise(rb_eArgError, "wrong number of arguments (%d for 0 to 2)", argc);
    }

    Data_Get_Struct(self, Pixel, pixel);

    info = CloneImageInfo(NULL);
    image = rm_acquire_image(info);
    (void) DestroyImageInfo(info);

    if (!image)
    {
        rb_raise(rb_eNoMemError, "not enough memory to continue.");
    }

    image->depth = depth;
    image->matte = matte;

    rm_init_magickpixel(image, &mpp);
    rm_set_magick_pixel_packet(pixel, &mpp);

    exception = AcquireExceptionInfo();

    // Support for hex-format color names moved out of QueryMagickColorname
    // in 6.4.1-9. The 'hex' argument was removed as well.
    if (hex)
    {
        if (compliance == XPMCompliance)
        {
            mpp.matte = MagickFalse;
            mpp.depth = (unsigned long) min(1.0 * image->depth, 16.0);
        }
        (void) GetColorTuple(&mpp, MagickTrue, name);
    }
    else
    {
        (void) QueryMagickColorname(image, &mpp, compliance, name, exception);
    }

    (void) DestroyImage(image);
    CHECK_EXCEPTION()
    (void) DestroyExceptionInfo(exception);

    // Always return a string, even if it's ""
    return rb_str_new2(name);
}

#to_hsla ⇒ Object

Return [hue, saturation, lightness, alpha] in the same ranges as Pixel_from_hsla.

Ruby usage:

- @verbatim Pixel#to_hsla @endverbatim

Parameters:

  • self —

    this object

Returns:

  • an array with hsla data

See Also:

  • Pixel_from_hsla


936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
 
# File 'ext/RMagick/rmpixel.c', line 936

VALUE
Pixel_to_hsla(VALUE self)
{
    double hue, sat, lum, alpha;
    Pixel *pixel;
    VALUE hsla;

    Data_Get_Struct(self, Pixel, pixel);

    ConvertRGBToHSL(pixel->red, pixel->green, pixel->blue, &hue, &sat, &lum);
    hue *= 360.0;
    sat *= 255.0;
    lum *= 255.0;

    if (pixel->opacity == OpaqueOpacity)
    {
        alpha = 1.0;
    }
    else if (pixel->opacity == TransparentOpacity)
    {
        alpha = 0.0;
    }
    else
    {
        alpha = (double)(QuantumRange - pixel->opacity) / (double)QuantumRange;
    }

    hsla = rb_ary_new3(4, rb_float_new(hue), rb_float_new(sat), rb_float_new(lum), rb_float_new(alpha));

    RB_GC_GUARD(hsla);

    return hsla;
}

#to_s ⇒ Object

Create a string representation of a Magick::Pixel.

Ruby usage:

- @verbatim Magick::Pixel#to_s @endverbatim

Parameters:

  • self —

    this object

Returns:

  • the string



1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
 
# File 'ext/RMagick/rmpixel.c', line 1114

VALUE
Pixel_to_s(VALUE self)
{
    Pixel *pixel;
    char buff[100];

    Data_Get_Struct(self, Pixel, pixel);
    sprintf(buff, "red=" QuantumFormat ", green=" QuantumFormat ", blue=" QuantumFormat ", alpha=" QuantumFormat,
            pixel->red, pixel->green, pixel->blue,
            (QuantumRange - pixel->opacity));
    return rb_str_new2(buff);
}