From 4c042bd5fa8f730d45864aff12736f68cd36a223 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Miloslav=20=C4=8C=C3=AD=C5=BE?= Date: Tue, 11 Jun 2019 12:03:19 +0200 Subject: [PATCH] Revert --- small3dlib.h | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-) diff --git a/small3dlib.h b/small3dlib.h index 4a1f9b6..1acbd70 100644 --- a/small3dlib.h +++ b/small3dlib.h @@ -145,8 +145,6 @@ BE REDEFINED, so rather don't do it (otherwise things may overflow etc.). */ #define S3L_FRACTIONS_PER_UNIT 512 -#define S3L_UNIT_MINUS_ONE (S3L_FRACTIONS_PER_UNIT - 1) - typedef int16_t S3L_ScreenCoord; typedef uint16_t S3L_Index; @@ -449,9 +447,10 @@ typedef struct vertices. These serve to locate the pixel on a triangle and interpolate values between it's three points. Each one goes from 0 to - S3L_UNIT_MINUS_ONE (inclidung) and the sum of the - three coordinates will always be exactly - S3L_UNIT_MINUS_ONE. */ + S3L_FRACTIONS_PER_UNIT (inclidung), but due to + rounding error may fall outside this range. The + sum of the three coordinates will always be + exactly S3L_FRACTIONS_PER_UNIT. */ S3L_Index triangleIndex; ///< Triangle index. S3L_Index modelIndex; S3L_Unit depth; ///< Depth (only if depth is turned on). @@ -1655,9 +1654,9 @@ void S3L_drawTriangle( #if S3L_FLAT p.depth = (tPointPP->z + lPointPP->z + rPointPP->z) / 3; - *barycentric0 = S3L_UNIT_MINUS_ONE / 3; - *barycentric1 = S3L_UNIT_MINUS_ONE / 3; - *barycentric2 = S3L_UNIT_MINUS_ONE - 2 * (S3L_UNIT_MINUS_ONE / 3); + *barycentric0 = S3L_FRACTIONS_PER_UNIT / 3; + *barycentric1 = S3L_FRACTIONS_PER_UNIT / 3; + *barycentric2 = S3L_FRACTIONS_PER_UNIT - 2 * (S3L_FRACTIONS_PER_UNIT / 3); #endif p.triangleSize[0] = rPointSx - lPointSx; @@ -1739,12 +1738,12 @@ void S3L_drawTriangle( s##Dx = p2##PointSx - p1##PointSx;\ s##Dy = p2##PointSy - p1##PointSy;\ initDepthFLS(s,p1,p2)\ - s##SideFLS.stepScaled = (S3L_UNIT_MINUS_ONE << S3L_FAST_LERP_QUALITY)\ + s##SideFLS.stepScaled = (S3L_FRACTIONS_PER_UNIT << S3L_FAST_LERP_QUALITY)\ / (s##Dy != 0 ? s##Dy : 1);\ s##SideFLS.valueScaled = 0;\ if (!down)\ {\ - s##SideFLS.valueScaled = S3L_UNIT_MINUS_ONE << S3L_FAST_LERP_QUALITY;\ + s##SideFLS.valueScaled = S3L_FRACTIONS_PER_UNIT << S3L_FAST_LERP_QUALITY;\ s##SideFLS.stepScaled *= -1;\ }\ s##Inc = s##Dx >= 0 ? 1 : -1;\ @@ -1819,7 +1818,7 @@ void S3L_drawTriangle( S3L_Unit *tmp = barycentric##b0;\ barycentric##b0 = barycentric##b1;\ barycentric##b1 = tmp;\ - s0##SideFLS.valueScaled = (S3L_UNIT_MINUS_ONE\ + s0##SideFLS.valueScaled = (S3L_FRACTIONS_PER_UNIT\ << S3L_FAST_LERP_QUALITY) - s0##SideFLS.valueScaled;\ s0##SideFLS.stepScaled *= -1;\ manageSplitPerspective(s0,s1) @@ -1926,7 +1925,7 @@ void S3L_drawTriangle( S3L_FastLerpState depthPC, b0PC, b1PC; depthPC.valueScaled = - ((S3L_UNIT_MINUS_ONE * S3L_FRACTIONS_PER_UNIT) / + ((S3L_FRACTIONS_PER_UNIT * S3L_FRACTIONS_PER_UNIT) / S3L_nonZero(S3L_interpolate(lRecipZ,rRecipZ,i,rowLength))) << S3L_FAST_LERP_QUALITY; @@ -1957,7 +1956,7 @@ void S3L_drawTriangle( #if S3L_COMPUTE_DEPTH #if S3L_PERSPECTIVE_CORRECTION == 1 - p.depth = (S3L_UNIT_MINUS_ONE * S3L_FRACTIONS_PER_UNIT) / + p.depth = (S3L_FRACTIONS_PER_UNIT * S3L_FRACTIONS_PER_UNIT) / S3L_nonZero(S3L_interpolate(lRecipZ,rRecipZ,i,rowLength)); #elif S3L_PERSPECTIVE_CORRECTION == 2 if (rowCount >= S3L_PC_APPROX_LENGTH) @@ -1968,7 +1967,7 @@ void S3L_drawTriangle( S3L_Unit nextDepth = ( - (S3L_UNIT_MINUS_ONE * S3L_FRACTIONS_PER_UNIT) / + (S3L_FRACTIONS_PER_UNIT * S3L_FRACTIONS_PER_UNIT) / S3L_nonZero(S3L_interpolate(lRecipZ,rRecipZ,nextI,rowLength)) ) << S3L_FAST_LERP_QUALITY; @@ -2032,7 +2031,7 @@ void S3L_drawTriangle( #endif *barycentric2 = - S3L_UNIT_MINUS_ONE - *barycentric0 - *barycentric1; + S3L_FRACTIONS_PER_UNIT - *barycentric0 - *barycentric1; #endif S3L_PIXEL_FUNCTION(&p); }