bytesperline.c - vx32 - Local 9vx git repository for patches.
(HTM) git clone git://r-36.net/vx32
(DIR) Log
(DIR) Files
(DIR) Refs
---
bytesperline.c (617B)
---
1 #include "u.h"
2 #include "lib.h"
3 #include "draw.h"
4
5 static
6 int
7 unitsperline(Rectangle r, int d, int bitsperunit)
8 {
9 ulong l, t;
10
11 if(d <= 0 || d > 32) /* being called wrong. d is image depth. */
12 abort();
13
14 if(r.min.x >= 0){
15 l = (r.max.x*d+bitsperunit-1)/bitsperunit;
16 l -= (r.min.x*d)/bitsperunit;
17 }else{ /* make positive before divide */
18 t = (-r.min.x*d+bitsperunit-1)/bitsperunit;
19 l = t+(r.max.x*d+bitsperunit-1)/bitsperunit;
20 }
21 return l;
22 }
23
24 int
25 wordsperline(Rectangle r, int d)
26 {
27 return unitsperline(r, d, 8*sizeof(uint32));
28 }
29
30 int
31 bytesperline(Rectangle r, int d)
32 {
33 return unitsperline(r, d, 8);
34 }