Class: Skia::Image

Inherits:
Base
  • Object
show all
Defined in:
lib/skia/image.rb

Instance Attribute Summary

Attributes inherited from Base

#ptr

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Base

#null?, release_callback, #to_ptr

Constructor Details

#initialize(ptr) ⇒ Image

Returns a new instance of Image.



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# File 'lib/skia/image.rb', line 5

def initialize(ptr)
  super(ptr, :sk_image_unref)
end

Class Method Details

.from_bitmap(bitmap) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/skia/image.rb', line 25

def self.from_bitmap(bitmap)
  raise ArgumentError, 'bitmap must be a Skia::Bitmap' unless bitmap.is_a?(Bitmap)

  ptr = Native.sk_image_new_from_bitmap(bitmap.ptr)
  raise DecodingError, 'Failed to create image from bitmap' if ptr.nil? || ptr.null?

  new(ptr)
end

.from_data(data) ⇒ Object

Raises:



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# File 'lib/skia/image.rb', line 17

def self.from_data(data)
  data_obj = data.is_a?(Data) ? data : Data.new(data)
  ptr = Native.sk_image_new_from_encoded(data_obj.ptr)
  raise DecodingError, 'Failed to decode image data' if ptr.nil? || ptr.null?

  new(ptr)
end

.from_file(path) ⇒ Object

Raises:



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# File 'lib/skia/image.rb', line 9

def self.from_file(path)
  data = Data.from_file(path)
  ptr = Native.sk_image_new_from_encoded(data.ptr)
  raise DecodingError, "Failed to decode image: #{path}" if ptr.nil? || ptr.null?

  new(ptr)
end

Instance Method Details

#alpha_type ⇒ Object 



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# File 'lib/skia/image.rb', line 50

def alpha_type
  Native.sk_image_get_alpha_type(@ptr)
end

#color_space ⇒ Object 



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# File 'lib/skia/image.rb', line 54

def color_space
  ColorSpace.wrap(Native.sk_image_get_colorspace(@ptr), retain: true)
end

#color_type ⇒ Object 



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# File 'lib/skia/image.rb', line 46

def color_type
  Native.sk_image_get_color_type(@ptr)
end

#encode(format = :png, quality = 100) ⇒ Object

Raises:



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# File 'lib/skia/image.rb', line 116

def encode(format = :png, quality = 100)
  # Create a pixmap to hold the image pixels
  pixmap = Native.sk_pixmap_new
  raise EncodingError, 'Failed to create pixmap' if pixmap.nil? || pixmap.null?

  begin
    # Peek pixels from the image into the pixmap
    raise EncodingError, 'Failed to peek pixels from image' unless Native.sk_image_peek_pixels(@ptr, pixmap)

    stream = Native.sk_dynamicmemorywstream_new
    raise EncodingError, 'Failed to create stream' if stream.nil? || stream.null?

    begin
      success = case format
                when :png
                  options = Native::SKPngEncoderOptions.new
                  options[:fFilterFlags] = :all
                  options[:fZLibLevel] = 6
                  options[:fComments] = nil
                  options[:fICCProfile] = nil
                  options[:fICCProfileDescription] = nil
                  Native.sk_pngencoder_encode(stream, pixmap, options)
                when :jpeg, :jpg
                  options = Native::SKJpegEncoderOptions.new
                  options[:fQuality] = quality
                  options[:fDownsample] = :downsample_420
                  options[:fAlphaOption] = :ignore
                  options[:xmpMetadata] = nil
                  options[:fICCProfile] = nil
                  options[:fICCProfileDescription] = nil
                  Native.sk_jpegencoder_encode(stream, pixmap, options)
                when :webp
                  options = Native::SKWebpEncoderOptions.new
                  options[:fCompression] = :lossy
                  options[:fQuality] = quality.to_f
                  options[:fICCProfile] = nil
                  options[:fICCProfileDescription] = nil
                  Native.sk_webpencoder_encode(stream, pixmap, options)
                else
                  options = Native::SKPngEncoderOptions.new
                  options[:fFilterFlags] = :all
                  options[:fZLibLevel] = 6
                  options[:fComments] = nil
                  options[:fICCProfile] = nil
                  options[:fICCProfileDescription] = nil
                  Native.sk_pngencoder_encode(stream, pixmap, options)
                end

      raise EncodingError, "Failed to encode image as #{format}" unless success

      data_ptr = Native.sk_dynamicmemorywstream_detach_as_data(stream)
      raise EncodingError, 'Failed to get encoded data' if data_ptr.nil? || data_ptr.null?

      Data.new(data_ptr)
    ensure
      Native.sk_dynamicmemorywstream_destroy(stream)
    end
  ensure
    Native.sk_pixmap_destructor(pixmap)
  end
end

#encoded_data ⇒ Object 



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# File 'lib/skia/image.rb', line 58

def encoded_data
  ptr = Native.sk_image_ref_encoded(@ptr)
  return encode(:png) if ptr.nil? || ptr.null?

  Data.new(ptr)
end

#height ⇒ Object 



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# File 'lib/skia/image.rb', line 38

def height
  Native.sk_image_get_height(@ptr)
end

#make_shader(tile_x: :clamp, tile_y: :clamp, matrix: nil) ⇒ Object

Raises:



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# File 'lib/skia/image.rb', line 65

def make_shader(tile_x: :clamp, tile_y: :clamp, matrix: nil)
  matrix_struct = matrix&.to_struct
  sampling = Native::SKSamplingOptions.new
  sampling[:fMaxAniso] = 0
  sampling[:fUseCubic] = 0
  sampling[:fCubicB] = 0.0
  sampling[:fCubicC] = 0.0
  sampling[:fFilter] = :nearest
  sampling[:fMipmap] = :none

  ptr = Native.sk_image_make_shader(@ptr, tile_x, tile_y, sampling, matrix_struct)
  raise Error, 'Failed to create shader from image' if ptr.nil? || ptr.null?

  Shader.new(ptr)
end

#peek_pixels ⇒ Object 



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# File 'lib/skia/image.rb', line 109

def peek_pixels
  pixmap = Pixmap.new
  return nil unless Native.sk_image_peek_pixels(@ptr, pixmap.ptr)

  pixmap
end

#read_pixels(width: nil, height: nil, src_x: 0, src_y: 0, row_bytes: nil, image_info: nil, color_type: :rgba_8888, alpha_type: :premul, color_space: nil, caching_hint: :allow) ⇒ Object

Raises:



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# File 'lib/skia/image.rb', line 89

def read_pixels(width: nil, height: nil, src_x: 0, src_y: 0, row_bytes: nil, image_info: nil, color_type: :rgba_8888,
                alpha_type: :premul, color_space: nil, caching_hint: :allow)
  info = image_info || ImageInfo.new(
    width: width || (self.width - src_x),
    height: height || (self.height - src_y),
    color_type: color_type,
    alpha_type: alpha_type,
    color_space: color_space
  )

  row_bytes ||= info.min_row_bytes
  byte_size = row_bytes * info.height
  pixels = FFI::MemoryPointer.new(:uint8, byte_size)

  success = Native.sk_image_read_pixels(@ptr, info.to_struct, pixels, row_bytes, src_x.to_i, src_y.to_i, caching_hint)
  raise DecodingError, 'Failed to read pixels from image' unless success

  pixels.read_bytes(byte_size)
end

#save(path, format: nil, quality: 100) ⇒ Object 



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# File 'lib/skia/image.rb', line 178

def save(path, format: nil, quality: 100)
  format ||= detect_format_from_path(path)
  data = encode(format, quality)
  File.binwrite(path, data.to_s)
  self
end

#save_jpeg(path, quality = 80) ⇒ Object 



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# File 'lib/skia/image.rb', line 189

def save_jpeg(path, quality = 80)
  save(path, format: :jpeg, quality: quality)
end

#save_png(path, quality = 100) ⇒ Object 



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# File 'lib/skia/image.rb', line 185

def save_png(path, quality = 100)
  save(path, format: :png, quality: quality)
end

#save_webp(path, quality = 80) ⇒ Object 



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# File 'lib/skia/image.rb', line 193

def save_webp(path, quality = 80)
  save(path, format: :webp, quality: quality)
end

#subset(rect) ⇒ Object 



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# File 'lib/skia/image.rb', line 81

def subset(rect)
  rect_struct = rect.to_struct
  ptr = Native.sk_image_make_subset_raster(@ptr, rect_struct)
  return nil if ptr.nil? || ptr.null?

  self.class.new(ptr)
end

#unique_id ⇒ Object 



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# File 'lib/skia/image.rb', line 42

def unique_id
  Native.sk_image_get_unique_id(@ptr)
end

#width ⇒ Object 



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# File 'lib/skia/image.rb', line 34

def width
  Native.sk_image_get_width(@ptr)
end