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| author | Vincent Sanders <vince@netsurf-browser.org> | 2011-03-12 17:46:11 +0000 |
|---|---|---|
| committer | Vincent Sanders <vince@netsurf-browser.org> | 2011-03-12 17:46:11 +0000 |
| commit | 74f108ee4dc5b915dfc8de0f88485245831ea7a9 (patch) | |
| tree | 68ede86e02c521b1c10b31cd2c5b57fd8984256d /css/utils.c | |
| parent | bdb05fa08abe1781827a3c095f26d7d0ac4dbe82 (diff) | |
| download | netsurf-74f108ee4dc5b915dfc8de0f88485245831ea7a9.tar.gz netsurf-74f108ee4dc5b915dfc8de0f88485245831ea7a9.tar.bz2 | |
Saturated maths in css fixed point
svn path=/trunk/netsurf/; revision=11975
Diffstat (limited to 'css/utils.c')
| -rw-r--r-- | css/utils.c | 27 |
1 files changed, 13 insertions, 14 deletions
diff --git a/css/utils.c b/css/utils.c index 11a14e174..422d0fbb1 100644 --- a/css/utils.c +++ b/css/utils.c @@ -25,7 +25,7 @@ #include "utils/log.h" /** Screen DPI in fixed point units: defaults to 90, which RISC OS uses */ -css_fixed nscss_screen_dpi = INTTOFIX(90); +css_fixed nscss_screen_dpi = F_90; /** * Convert an absolute CSS length to points. @@ -42,18 +42,18 @@ css_fixed nscss_len2pt(css_fixed length, css_unit unit) switch (unit) { /* We assume the screen and any other output has the same dpi */ /* 1in = DPIpx => 1px = (72/DPI)pt */ - case CSS_UNIT_PX: return FDIV(FMULI(length, 72), nscss_screen_dpi); + case CSS_UNIT_PX: return FDIV(FMUL(length, F_72), nscss_screen_dpi); /* 1in = 72pt */ - case CSS_UNIT_IN: return FMULI(length, 72); + case CSS_UNIT_IN: return FMUL(length, F_72); /* 1in = 2.54cm => 1cm = (72/2.54)pt */ case CSS_UNIT_CM: return FMUL(length, - FDIV(INTTOFIX(72), FLTTOFIX(2.54))); + FDIV(F_72, FLTTOFIX(2.54))); /* 1in = 25.4mm => 1mm = (72/25.4)pt */ case CSS_UNIT_MM: return FMUL(length, - FDIV(INTTOFIX(72), FLTTOFIX(25.4))); + FDIV(F_72, FLTTOFIX(25.4))); case CSS_UNIT_PT: return length; /* 1pc = 12pt */ - case CSS_UNIT_PC: return FMULI(length, 12); + case CSS_UNIT_PC: return FMUL(length, INTTOFIX(12)); default: break; } @@ -91,14 +91,13 @@ css_fixed nscss_len2px(css_fixed length, css_unit unit, font_size = nscss_len2pt(font_size, font_unit); /* Clamp to configured minimum */ - if (font_size < FDIVI(INTTOFIX(option_font_min_size), 10)) { - font_size = FDIVI(INTTOFIX(option_font_min_size), 10); + if (font_size < FDIV(INTTOFIX(option_font_min_size), F_10)) { + font_size = FDIV(INTTOFIX(option_font_min_size), F_10); } /* Convert to pixels (manually, to maximise precision) * 1in = 72pt => 1pt = (DPI/72)px */ - px_per_unit = FDIV(FMUL(font_size, nscss_screen_dpi), - INTTOFIX(72)); + px_per_unit = FDIV(FMUL(font_size, nscss_screen_dpi), F_72); /* Scale ex units: we use a fixed ratio of 1ex = 0.6em */ if (unit == CSS_UNIT_EX) @@ -106,7 +105,7 @@ css_fixed nscss_len2px(css_fixed length, css_unit unit, } break; case CSS_UNIT_PX: - px_per_unit = INTTOFIX(1); + px_per_unit = F_1; break; /* 1in = DPIpx */ case CSS_UNIT_IN: @@ -122,7 +121,7 @@ css_fixed nscss_len2px(css_fixed length, css_unit unit, break; /* 1in = 72pt => 1pt = (DPI/72)px */ case CSS_UNIT_PT: - px_per_unit = FDIV(nscss_screen_dpi, INTTOFIX(72)); + px_per_unit = FDIV(nscss_screen_dpi, F_72); break; /* 1pc = 12pt => 1in = 6pc => 1pc = (DPI/6)px */ case CSS_UNIT_PC: @@ -135,9 +134,9 @@ css_fixed nscss_len2px(css_fixed length, css_unit unit, /* Ensure we round px_per_unit to the nearest whole number of pixels: * the use of FIXTOINT() below will truncate. */ - px_per_unit += FLTTOFIX(0.5); + px_per_unit += F_0_5; /* Calculate total number of pixels */ - return FMULI(length, FIXTOINT(px_per_unit)); + return FMUL(length, TRUNCATEFIX(px_per_unit)); } |