deepstone
changeset 40:1fa939507d8b
fast floating point->int conversion
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Fri, 15 Sep 2017 05:00:37 +0300 |
| parents | f9b1ff21fd62 |
| children | 482f30e63462 |
| files | src/fixedp.h src/mglimpl.h src/scantmpl.h |
| diffstat | 3 files changed, 11 insertions(+), 2 deletions(-) [+] |
line diff
1.1 --- a/src/fixedp.h Mon Mar 10 17:28:28 2014 +0200 1.2 +++ b/src/fixedp.h Fri Sep 15 05:00:37 2017 +0300 1.3 @@ -31,6 +31,12 @@ 1.4 extern const fixed fixed_tenth; 1.5 extern const fixed fixed_255;*/ 1.6 1.7 +static __inline long cround64(double val) 1.8 +{ 1.9 + val += 6755399441055744.0; 1.10 + return *(long*)&val; 1.11 +} 1.12 + 1.13 #ifdef DBG_USE_FLOAT 1.14 /* ------- debug mode, use floating point -------- */ 1.15 #define FIXED_INT_PART(n) ((int)(n))
2.1 --- a/src/mglimpl.h Mon Mar 10 17:28:28 2014 +0200 2.2 +++ b/src/mglimpl.h Fri Sep 15 05:00:37 2017 +0300 2.3 @@ -14,7 +14,8 @@ 2.4 #define ZTILE(x) (((x) & ~ZTILE_MASK) >> ZTILE_SHIFT) 2.5 #define ZTILE_OFFS(x) ((x) & ZTILE_MASK) 2.6 2.7 -#define ROUND(x) ((x) >= 0.0 ? (x) + 0.5 : (x) - 0.5) 2.8 +/*#define ROUND(x) ((x) >= 0.0 ? (x) + 0.5 : (x) - 0.5)*/ 2.9 +#define ROUND(x) cround64(x) 2.10 2.11 2.12 typedef float mat4_t[16];
3.1 --- a/src/scantmpl.h Mon Mar 10 17:28:28 2014 +0200 3.2 +++ b/src/scantmpl.h Fri Sep 15 05:00:37 2017 +0300 3.3 @@ -251,7 +251,9 @@ 3.4 #ifdef INTERP_DEPTH 3.5 long pix = (sline + x0 + i) - fb->pixels; 3.6 #ifdef RAST_FLOAT 3.7 - unsigned short zval = (unsigned short)(z * USHRT_MAX); 3.8 + /*unsigned short zval = (unsigned short)(z * USHRT_MAX);*/ 3.9 + float zn = z + 1.0; 3.10 + unsigned short zval = ((*(long*)&zn) & 0x7fffff) >> 7; 3.11 #else 3.12 unsigned short zval = (unsigned short)((z >> 1) & 0xffff); 3.13 #endif