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| author | Lars-Dominik Braun <lars@6xq.net> | 2019-02-04 13:09:03 +0100 |
|---|---|---|
| committer | Lars-Dominik Braun <lars@6xq.net> | 2019-02-04 13:09:03 +0100 |
| commit | 04e68443040c7abad84d66477e98f93bed701760 (patch) | |
| tree | 2b6202afae659e773bf6916157d23e83edfa44e3 /app/mpg/2.2/src/matrix printer | |
| download | eumel-src-04e68443040c7abad84d66477e98f93bed701760.tar.gz eumel-src-04e68443040c7abad84d66477e98f93bed701760.tar.bz2 eumel-src-04e68443040c7abad84d66477e98f93bed701760.zip | |
Initial import
Diffstat (limited to 'app/mpg/2.2/src/matrix printer')
| -rw-r--r-- | app/mpg/2.2/src/matrix printer | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/app/mpg/2.2/src/matrix printer b/app/mpg/2.2/src/matrix printer new file mode 100644 index 0000000..66157cf --- /dev/null +++ b/app/mpg/2.2/src/matrix printer @@ -0,0 +1,130 @@ +(* Version vom 21.10.87 BJ *) +(* Standardoperationen *) +(* printer line - Linienalgorithmus *) +(* printer fill - Fuellalgorithmus *) + +PROC printer line (INT CONST x1,y1,x2,y2, + PROC (INT CONST, INT CONST) p set pixel): + INT VAR x,y,z, + a,b,d, + dx :: abs(x2-x1), + dy :: abs(y2-y1), + dp,dq; + IF dx <> 0 AND dy <> 0 + THEN IF dy <= dx + THEN draw line 1 + ELSE draw line 2 + FI + ELSE IF dx = 0 AND dy <> 0 + THEN draw vertical line + ELSE draw horizontal line + FI + FI. + + draw line 1: + x := x1; + y := y1; + z := x2; + a := sign(x2-x1); + b := sign(y2-y1); + dp := dy * 2; + d := dp - dx; + dq := dp - 2 * dx; + setpoint; + WHILE x <> z REP + x := x + a; + IF d < 0 + THEN d := d + dp + ELSE y := y + b; + d := d + dq + FI; + setpoint + PER. + + draw line 2: + x := x1; + y := y1; + z := y2; + b := sign(x2-x1); + a := sign(y2-y1); + dp := dx * 2; + d := dp - dy; + dq := dp - 2 * dy; + setpoint; + WHILE y <> z REP + y := y + a; + IF d < 0 + THEN d := d + dp + ELSE x := x + b; + d := d + dq + FI; + setpoint + PER. + + draw vertical line: + a := sign(y2-y1); + x := x1; + y := y1; + z := y2; + setpoint; + WHILE y <> z REP + y := y + a; + setpoint + PER. + + draw horizontal line: + a := sign(x2-x1); + x := x1; + y := y1; + z := x2; + setpoint; + WHILE x <> z REP + x := x + a; + setpoint + PER. + + setpoint: + p set pixel (x,y) +END PROC printer line; + +PROC printer fill (INT CONST xl, xr, y, dir, + BOOL PROC (INT CONST, INT CONST) point, + PROC (INT CONST, INT CONST) pset): + INT VAR xl1 :: xl; + WHILE point(xl1,y) REP + xl1 INCR 1; + IF xl1 >= xr + THEN LEAVE printer fill + FI + PER; + INT VAR xrn :: xl1+1, + xln :: xl1; + WHILE NOT point(xrn,y) REP + pset(xrn,y); + xrn INCR 1 + PER; + WHILE NOT point(xln,y) REP + pset(xln,y); + xln DECR 1 + PER; + IF xrn > xr + THEN printer fill (xr, xrn-1,y-dir,-dir, + BOOL PROC (INT CONST, INT CONST) point, + PROC (INT CONST, INT CONST) pset) + ELSE printer fill (xrn, xr, y, dir, + BOOL PROC (INT CONST, INT CONST) point, + PROC (INT CONST, INT CONST) pset) + FI; + IF xln < xl + THEN printer fill (xln+1,xl, y-dir,-dir, + BOOL PROC (INT CONST, INT CONST) point, + PROC (INT CONST, INT CONST) pset) + ELSE printer fill (xl,xln, y, dir, + BOOL PROC (INT CONST, INT CONST) point, + PROC (INT CONST, INT CONST) pset) + FI; + printer fill(xln+1, xrn-1, y+dir, dir, + BOOL PROC (INT CONST, INT CONST) point, + PROC (INT CONST, INT CONST) pset) +END PROC printer fill; + |