| Operators |
set_rgba — Set the color definition via RGBA values.
set_rgba( : : WindowHandle, Red, Green, Blue, Alpha : )
set_rgba sets the output color(s) or the gray values, respectively, for region output for the window. The colors are defined with the red, green, blue, and alpha components. If only one combination is passed, all output takes place in that color. If a tuple is passed, region output and output of geometric objects takes place modulo the passed colors.
For every call of an output operator, output is started with the first color. If only one object is displayed per call, it will always be displayed in the first color. This is even true for objects with multiple connection components. If multiple objects are displayed per operator call, multiple colors are used. The defined colors are used until set_color, set_rgba, or set_rgb is called again. The values are used by operators like disp_region, disp_line, disp_rectangle1, disp_rectangle2, disp_arrow, etc.
set_rgba depends on the library libcanvas, which might not be available on embedded systems.
Window handle.
Red component of the color.
Default value: 255
Typical range of values: 0 ≤ Red ≤ 255
Restriction: 0 <= Red && Red <= 255
Green component of the color.
Default value: 0
Typical range of values: 0 ≤ Green ≤ 255
Restriction: 0 <= Green && Green <= 255
Blue component of the color.
Default value: 0
Typical range of values: 0 ≤ Blue ≤ 255
Restriction: 0 <= Blue && Blue <= 255
Alpha component of the color.
Default value: 255
Typical range of values: 0 ≤ Alpha ≤ 255
Restriction: 0 <= Alpha && Alpha <= 255
set_rgba returns 2 (H_MSG_TRUE) if the window is valid and all passed colors are available and displayable. Otherwise an exception is raised.
Foundation
| Operators |