2 Position Operations
A position is a pixel location within a viewport. The upper-left corner is pixel (0, 0), and positions increase to the right and down.
Represents a positions.
Returns the color of the pixel at position p in
viewport; 0 denotes white and 1 denotes not
white.
| ((get-color-pixel viewport) p) → rgb? |
| viewport : viewport? |
| p : posn? |
Returns an rgb value for color of the pixel at position
p in viewport.
| ((test-pixel viewport) color) → rgb? | |||||||||
| viewport : viewport? | |||||||||
|
Returns the color that will actually be used if color is used
to draw.