static uint16_t to_region_code(const char *region)
{
#define REGION_CODE(r, c) if (!strcasecmp(region, r)) return c
REGION_CODE("NA", 0x0001);
REGION_CODE("WW", 0x0002);
REGION_CODE("GR", 0x0003);
REGION_CODE("PR", 0x0004);
REGION_CODE("RU", 0x0005);
REGION_CODE("BZ", 0x0006);
REGION_CODE("IN", 0x0007);
REGION_CODE("KO", 0x0008);
REGION_CODE("JP", 0x0009);
#undef REGION_CODE
return 0;
}
DFBBoolean
dfb_clip_line( const DFBRegion *clip, DFBRegion *line )
{
unsigned char region_code1 = REGION_CODE( line->x1, line->y1,
clip->x1,
clip->x2,
clip->y1,
clip->y2 );
unsigned char region_code2 = REGION_CODE( line->x2, line->y2,
clip->x1,
clip->x2,
clip->y1,
clip->y2 );
while (region_code1 | region_code2) {
/* line completely outside the clipping rectangle */
if (region_code1 & region_code2)
return DFB_FALSE;
if (region_code1) {
if (region_code1 & 8) { /* divide line at bottom*/
line->x1 = line->x1 +(line->x2-line->x1) * (clip->y2 - line->y1) / (line->y2-line->y1);
line->y1 = clip->y2;
}
else if (region_code1 & 4) { /* divide line at top*/
line->x1 = line->x1 +(line->x2-line->x1) * (clip->y1 - line->y1) / (line->y2-line->y1);
line->y1 = clip->y1;
}
else if (region_code1 & 2) { /* divide line at right*/
line->y1 = line->y1 +(line->y2-line->y1) * (clip->x2 - line->x1) / (line->x2-line->x1);
line->x1 = clip->x2;
}
else if (region_code1 & 1) { /* divide line at right*/
line->y1 = line->y1 +(line->y2-line->y1) * (clip->x1 - line->x1) / (line->x2-line->x1);
line->x1 = clip->x1;
}
region_code1 = REGION_CODE( line->x1, line->y1,
clip->x1,
clip->x2,
clip->y1,
clip->y2 );
}
else {
if (region_code2 & 8) { /* divide line at bottom*/
line->x2 = line->x1 +(line->x2-line->x1) * (clip->y2 - line->y1) / (line->y2-line->y1);
line->y2 = clip->y2;
}
else if (region_code2 & 4) { /* divide line at top*/
line->x2 = line->x1 +(line->x2-line->x1) * (clip->y1 - line->y1) / (line->y2-line->y1);
line->y2 = clip->y1;
}
else if (region_code2 & 2) { /* divide line at right*/
line->y2 = line->y1 +(line->y2-line->y1) * (clip->x2 - line->x1) / (line->x2-line->x1);
line->x2 = clip->x2;
}
else if (region_code2 & 1) { /* divide line at right*/
line->y2 = line->y1 +(line->y2-line->y1) * (clip->x1 - line->x1) / (line->x2-line->x1);
line->x2 = clip->x1;
}
region_code2 = REGION_CODE( line->x2, line->y2, clip->x1,
clip->x2,
clip->y1,
clip->y2 );
}
}
/* successfully clipped or clipping not neccessary */
return DFB_TRUE;
}
