Commodore Plus 4 - Page 228

216 Programming Graphics
2 = the shape is ORed with the background
3 = the shape is ANDed with the background
4 = the shape is XORed with the background
The effect of this parameter depends on the actual bit patterns used in the shape
and on the background. In multicolor mode, the bit patterns are determined by
which color sources (0-3) are used to draw the shape. Tables 4-3 through 4-7
show the results of using each parameter value.
Table 4-3. Resulting Color Source Using a Parameter Value of 0
Color Source
Used in Shape
0
1
2
3
Table 4-4. Resulting
Color Source
Used in Shape
0
1
2
3
Table 4-5. Resulting
Color Source
Used in Shape
0
1
2
3
Color
0
0
1
2
3
Color:
Color
0
3
2
1
0
Color
Color
0
0
1
2
3
Source
1
0
1
2
3
Source
Source
1
3
2
1
0
Source
Source
1
1
1
3
3
Used on
2
0
1
2
3
Screen
3
0
1
2
3
Using a Parameter Value of 1
Used on
2
3
2
1
0
Screen
3
3
2
1
0
Using a Parameter Value of 2
• Used on
2
2
3
2
3
Screen
3
3
3
3
3