Figure

Table of Contents

• setPixel
• line
• dashedLine
• rectangle
• filledRectangle
• polygon
• filledPolygon
• arc
• fill
• fillToBorder
• copy
• copyResized

• setPixel

  function

  set the pixel at (x,y)

  format

  im.setPixel(x, y, color)

  source | setPixel.rb

  font = GD::Font.new('Large')
  im.string(font, 50, 50, "String", blue)
  im.string(GD::Font::LargeFont, 50, 100, "String", red)
  

  output(can you see?)

  

• line

  function

  draw a line

  format

  im.line(x1, y1, x2, y2, color)

  source | line.rb

  im.line(50, 50, 150, 50, black)
  

  output

  

• dashedLine

  function

  draw a dashed line

  format

  im.dashedLine(x1, y1, x2, y2, color)

  source | dashedline.rb

  im.dashedLine(50, 50, 150, 50, blue)
  

  output

  

• rectangle

  function

  draw a rectangle

  format

  im.rectangle(x1, y1, x2, y2, color)

  source | rectangle.rb

  im.rectangle(50, 50, 150, 150, blue)
  

  output

  

• filledRectangle

  function

  draw a filled rectangle

  format

  im.filledRectangle(x1, y1, x2, y2, color)

  source | filledrectangle.rb

  im.filledRectangle(50, 50, 150, 150, blue)
  

  output

  

• polygon

  function

  draw a polygon

  format

  im.polygon(polygon, color)
  polygon is Polygon Object

  source | polygon.rb

  poly = GD::Polygon.new
  poly.addPt(100,50)
  poly.addPt(50,100)
  poly.addPt(150,100)
  
  im.polygon(poly, blue)
  

  output

  

• filledPolygon

  function

  draw a filled polygon

  format

  im.filledPolygon(polygon, color)
  polygon is Polygon Object

  source | filledpolygon.rb

  poly = GD::Polygon.new
  poly.addPt(100,50)
  poly.addPt(50,100)
  poly.addPt(150,100)
  
  im.filledPolygon(poly, blue)
  

  output

  

• arc

  function

  draw arcs and ellipses

  format

  im.arc(cx, cy, width, heihgt, start, end, color)

  source | arc.rb

  im.arc(100, 50, 100, 50, 0, 270, blue)
  im.arc(100, 150, 100, 50, 90, 360, red)
  

  output

  

• fill

  function

  flood-fills regions

  format

  im.fill(x, y, color_name)

  source | fill.rb

  im.arc(100, 50, 100, 50, 0, 360, blue)
  im.fill(100, 50, red)
  
  im.arc(100, 150, 100, 50, 0, 360, blue)
  im.fill(100, 150, green)
  

  output

  

  source2 | fill2.rb

  im.arc(100, 50, 100, 50, 0, 360, blue)
  im.fill(100, 50, red)
  
  im.arc(100, 150, 100, 50, 0, 360, blue)
  im.fill(100, 190, green)
  

  output2

  

• fillToBorder

  function

  flood-fills regions with the specified color, starting at position (x,y). However, instead of stopping when it hits a pixel of a different color than the starting pixel.

  format

  im.fillToBorder(x, y, border_color, fill_color)

  source | filltoborder.rb

  im.arc(100, 50, 100, 50, 0, 360, blue)
  im.fillToBorder(100, 50, blue, red)
  

  output

  

  source2 | filltoborder2.rb
  if blue != green

  im.arc(100, 50, 100, 50, 0, 360, blue)
  im.fillToBorder(100, 50, green, white)
  

  output2

  

• copy

  function

  copy the specified region

  format

  im.copy(im, x, y, sx, sy, sw, sh)

  source | copy.rb

  im.filledRectangle(0, 0, 50, 50, red)
  im.filledRectangle(50, 0, 100, 50, green)
  im.filledRectangle(0, 50, 50, 100, blue)
  im.filledRectangle(50, 50, 100, 100, yellow)
  im.copy(im, 100, 100, 0, 0, 50, 50)
  

  output

  

  source2 | copy2.rb
  

  im.colorAllocate(255,255,255)
  im.colorAllocate(255,0,0)
  
  im2.filledRectangle(0, 0, 50, 50, red)
  im2.filledRectangle(50, 0, 100, 50, green)
  im2.filledRectangle(0, 50, 50, 100, blue)
  im2.filledRectangle(50, 50, 100, 100, yellow)
  im.copy(im2, 100, 100, 0, 0, 50, 50)
  

  output

  

  note

  'colorAllocate' may be necessary in destination image.

• copyResized

  function

  copy the specified region to different sizes

  format

  im.copyResized(im, x, y, sx, sy, w, h, sw, sh)

  source | copyresized.rb

  im.filledRectangle(0, 0, 50, 50, red)
  im.filledRectangle(50, 0, 100, 50, green)
  im.filledRectangle(0, 50, 50, 100, blue)
  im.filledRectangle(50, 50, 100, 100, yellow)
  im.copyResized(im, 100, 100, 0, 0, 30, 30, 50, 50)
  

  output