Class: Iup::Image

Inherits:
ImageWidget show all
Defined in:
lib/wrapped/image.rb

Overview

Image made from greyscale values. The colors are defined in a table, and their indices used when defining the image pixel-map.

Example

The following image is built from 3 colors: the pixmap gives their placement in the 11x11 image, and the constructor uses a block to specify the color for each of the 3 values. When displayed, the image presents a red X on a yellow background.

 pixmap_x = [
  1,2,3,3,3,3,3,3,3,2,1, 
  2,1,2,3,3,3,3,3,2,1,2, 
  3,2,1,2,3,3,3,2,1,2,3, 
  3,3,2,1,2,3,2,1,2,3,3, 
  3,3,3,2,1,2,1,2,3,3,3, 
  3,3,3,3,2,1,2,3,3,3,3, 
  3,3,3,2,1,2,1,2,3,3,3, 
  3,3,2,1,2,3,2,1,2,3,3, 
  3,2,1,2,3,3,3,2,1,2,3, 
  2,1,2,3,3,3,3,3,2,1,2, 
  1,2,3,3,3,3,3,3,3,2,1
]

img = Iup::Image.new(11, 11, pixmap_x) do |i|
 i.color(1, '0 1 0')
 i.color(2, '255 0 0')
 i.color(3, '255 255 0')
end

Instance Attribute Summary

Attributes inherited from Widget

#handle

Instance Method Summary collapse

Methods inherited from ImageWidget

#assign_handle, #bpp, #channels, #height, #hotspot, #rastersize, #save, #wid, #width

Methods inherited from Widget

#active, #assign_handle, #bgcolor, #destroy, #enterwindow_cb=, #fgcolor, #font, #getfocus_cb=, #help_cb=, #k_any=, #killfocus_cb=, #leavewindow_cb=, #map_cb=, #maxsize, #minsize, #open_controls, #size, #unmap_cb=, #visible, #wid, #zorder

Methods included from AttributeBuilders

#define_attribute, #define_id_attribute, #define_id_reader, #define_id_writer, #define_property_attribute, #define_property_reader, #define_property_writer, #define_reader, #define_writer

Methods included from CallbackSetter

#define_callback

Constructor Details

#initialize(width, height, pixels) {|_self| ... } ⇒ Image

Constructor creates an image from raw pixels, using 1-value per pixel. If a block is given, the new instance is yielded to it.

  • width - width of image in pixels

  • height - height of image in pixels

  • pixels - an array of pixel values, each value being a color index

Yields:

  • (_self)

Yield Parameters:

  • _self (Iup::Image) —

    the object that the method was called on



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# File 'lib/wrapped/image.rb', line 112

def initialize(width, height, pixels)
  @handle = IupLib.IupImage(width, height, IupLib.pointer_from_chars(pixels))

  # run any provided block on instance, to set up further attributes
  yield self if block_given?
end

Instance Method Details

#color(index, value = nil) ⇒ Object

:call-seq:

image.color(index)        # retrieves 
image.color(index, value) # sets

Access color at given index.

  • index - integer of color found in pixel map

  • value - ‘r g b’ representation of color



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# File 'lib/wrapped/image.rb', line 126

def color(index, value=nil)
  IupLib.IupSetAttribute(@handle, index.to_s, value)
end