gfxutils

A group of simple implementations for common utilities used in graphical applications:

• Vectors (2D)
  • Importing

      from gfxutils.vector import V2
  
      pi = 3.14159265358979323846264
  
      v1 = V2(x=10, y=10)
      assert v1.length == 14.14213562373095048
  
      v2 = V2.from_degrees_and_length(45, 14.14213562373095048)
      assert v1 == v2
      assert abs(v2.x - 10) < 0.0001
      assert abs(v2.y - 10) < 0.0001
  
      v3 = V2.from_radians_and_length(pi / 4, 14.14213562373095048)
      assert v1 == v3

  • Vector Math
    • Addition and Subtraction is element-wise vector math

        v1 = V2(x=10, y=20)
        v2 = V2(y=1)
        v3 = v1 + v2
        assert v3 == V2(10, 21)
        v4 = v3 - V2(x=5)
        assert v4 == V2(5, 21)
        v1 += v2
        assert v1 == v3
        v3 -= V2(x=5)
        assert v4 == v3

    • Multiplication and Division is Vector * Scalar and Vector / Scalar

        v1 = V2(x=10, y=20)
        v2 = v1 * 2
        assert v2 == V2(20, 40)
        v3 = v1 / 2
        assert v3 == V2(5, 10)
        v4 = v1.copy
        v4 *= 2
        assert v4 == V2(20, 40)
        v5 = v1.copy
        v5 /= 2
        assert v5 == V2(5, 10)

  • Angles are measured counterclockwise from the positive x axis

      v1 = V2(x=10, y=10)
      # within rounding of 45°
      assert abs(v1.degrees - 45) < 0.0001
      assert abs(v1.radians - pi / 4) < 0.0001
  
      v1.degrees += 45
      assert v1 == V2(y=v1.length)

  • Normalization (equivalent to setting the length to 1)

      v1 = V2(x=10, y=10)
      assert v1.length == 14.14213562373095048
  
      # create a normalized copy without modifying v1
      v2 = v1.normalized
      assert v1.length == 14.14213562373095048
      assert abs(v2.length - 1) < 0.0001
  
      # normalize v1 in-place
      v1.normalize()
      assert abs(v1.length - 1) < 0.0001

• Colors
  • Use a proper c-based library to manipulate bitmaps
    • A list of Color instances long enough to process a 1920x1080 bitmap (2,073,600 instances) will take several seconds to make
    • SDL2, pyglet, pillow, and numpy may be acceptable choices depending on your need
  • Creation of Color instances

      white = Color(red=1.0, green=1.0, blue=1.0)
      assert white.hex == '#FFFFFFFF'
  
      clear = Color(alpha=0.0)
      assert clear.hex == '#00000000'
  
      red = Color.from_hsb(hue=0.0, saturation=1.0, brightness=1.0)
      assert red.hex == '#FF0000FF'

  • Primary Colors

      red = Color(red=1.0)
      assert red.hex == '#FF0000FF'
  
      green = Color(green=1.0)
      assert green.hex == '#00FF00FF'
  
      blue = Color(blue=1.0)
      assert blue.hex == '#0000FFFF'

  • Transparency via an alpha channel

      transparent_black = Color(alpha=0.5)
      assert transparent_black.hex == '#0000007F'

  • Comparisons use equality

      red1 = Color(red=1.0)
      red2 = Color.from_hsb(hue=0.0, saturation=1.0, brightness=1.0)
      assert red1 == red2

  • Bytes built-in is supported

      green = Color(green=1.0, alpha=0.5)
      assert bytes(green) == b'\x00\xFF\x00\x7F'

• Shapes
  • Circle
    • Documentation Coming Soon
  • TODO:
    • Line
    • Triangle
    • Rectangle