Radio Shack TRS-80 Operation Manual page 38

Computer Graphics
- - - - - - - - - - T R S - a O
®
grid representing the pixel blank.
Operation Manual
4. On your paper grid, count each ON pixel as I and each
OFF pixel as
~.
List the binary numbers for each row
to the side of the grid. For example, you might have
~~~l l~~~
on the first row,
~lll ~~ll
on the second
row, etc.
5. Using a hexadecimal conversion chart, convert the
binary numbers to hexadecimal numbers. (Each row
equates to a two-digit hexadecimal number.)
6. Insert the hexadecimal numbers in a tile string and
enter the string in your program.
Note: For a listing of commonly used tiling styles, see
Appendix F.
Example
For example, if you're working on an 8 x 8 grid and want to
draw a plus
("+")
sign:
- - - - - - - - - - l I a d I 8 / h a e l l - - - - - - - - -
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