projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 97e3edfb DF |
1 | /* |
| 2 | * Copyright (c) 1980 Regents of the University of California. | |
| 3 | * All rights reserved. The Berkeley software License Agreement | |
| 4 | * specifies the terms and conditions for redistribution. | |
| 5 | */ | |
| 6 | ||
| 7 | #ifndef lint | |
| 8 | static char sccsid[] = "@(#)update.c 5.1 (Berkeley) %G%"; | |
| 9 | #endif not lint | |
| 10 | ||
| 9999bdc7 RC |
11 | /* |
| 12 | * update: the key output optimization routine of the whole editor. | |
| 13 | * The input consists of two bit matrices (mold is what's on the screen, | |
| 14 | * mnew is what we want to be on the screen) and the coordinates of | |
| 15 | * the lower left corner on the screen where this matrix is. | |
| 16 | * This routine does whatever is necessary to get the screen to look | |
| 17 | * like mnew, assuming that it currently looks like mold. | |
| 18 | * | |
| 19 | * (If I could patent this process for bread and other food I | |
| 20 | * would be a rich man.) | |
| 21 | */ | |
| 22 | ||
| 23 | #include "bit.h" | |
| 24 | ||
| 25 | update(mold, mnew, rows, cols, baser, basec) | |
| 26 | bitmat mold, mnew; | |
| 27 | int rows, cols, baser, basec; | |
| 28 | { | |
| 29 | int irow; | |
| 30 | register int i, j, k; | |
| 31 | int r1, r2, c1, c2, nr1, nr2, nc1, nc2; | |
| 32 | extern int QUIET; | |
| 33 | ||
| 34 | #ifdef TRACE | |
| 35 | if (trace) | |
| 36 | fprintf(trace, "update(mold=%x, mnew=%x, rows=%d, cols=%d, baser=%d, basec=%d)\n", mold, mnew, rows, cols, baser, basec); | |
| 37 | #endif | |
| 38 | ||
| 39 | if (QUIET) | |
| 40 | return; | |
| 41 | aminmax(mold, rows, cols, &r1, &c1, &r2, &c2); | |
| 42 | aminmax(mnew, rows, cols, &nr1, &nc1, &nr2, &nc2); | |
| 43 | r1 = min(r1, nr1); r2 = max(r2, nr2); | |
| 44 | c1 = min(c1, nc1); c2 = max(c2, nc2); | |
| 45 | ||
| 46 | dumpmat("mold:", mold, rows, cols); | |
| 47 | dumpmat("mnew:", mnew, rows, cols); | |
| 48 | ||
| 49 | for (i=r1; i<=r2; i++) { | |
| 50 | irow = baser + rows - i - 1; | |
| 51 | if (emptyrow(mnew, rows, cols, i)) { | |
| 52 | if (emptyrow(mold, rows, cols, i)) { | |
| 53 | continue; /* identically blank. skip. */ | |
| 54 | } | |
| 55 | /* | |
| 56 | * Row i is to be cleared. Look for some more | |
| 57 | * rows to clear and do it all at once. | |
| 58 | */ | |
| 59 | for (j=i+1; j<rows && emptyrow(mnew,rows,cols,j); j++) | |
| 60 | ; | |
| 61 | areaclear(baser+rows-j, basec, irow, basec+cols-1); | |
| 62 | i = j-1; /* skip the others */ | |
| 63 | } else for (j=c1; j<=c2; j++) { | |
| 64 | /* | |
| 65 | * Result row is not all blank. We look for stretches | |
| 66 | * of bits that have to be changed (in either | |
| 67 | * direction) and draw an exclusive or line over all | |
| 68 | * the bits in each stretch. | |
| 69 | */ | |
| 70 | if (mat(mold,rows,cols,i,j,1)!=mat(mnew,rows,cols,i,j,2)){ | |
| 71 | for (k=j+1; k<cols && mat(mold,rows,cols,i,k,3)!= | |
| 72 | mat(mnew,rows,cols,i,k,4); k++) | |
| 73 | ; | |
| 74 | k--; | |
| 75 | setxor(); | |
| 76 | line(basec+j, irow, basec+k, irow); | |
| 77 | j = k; /* skip the others */ | |
| 78 | } | |
| 79 | } | |
| 80 | } | |
| 81 | } |