From 8392d887637b4dd5c62b2dad2401eff84f1c884d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Miloslav=20=C4=8C=C3=AD=C5=BE?= Date: Thu, 9 May 2019 23:39:28 +0200 Subject: [PATCH] Start putting persp corr in place --- s3l.h | 125 +++++++++++++++++++++++++++++++++++++++++++++++++++--- testSDL.c | 5 ++- 2 files changed, 122 insertions(+), 8 deletions(-) diff --git a/s3l.h b/s3l.h index 2c72f55..b0fdf7b 100644 --- a/s3l.h +++ b/s3l.h @@ -599,12 +599,21 @@ static inline int16_t S3L_interpolate(int16_t v1, int16_t v2, int16_t t, Like S3L_interpolate, but uses a parameter that goes from 0 to S3L_FRACTIONS_PER_UNIT - 1, which can be faster. */ - static inline int16_t S3L_interpolateByUnit(int16_t v1, int16_t v2, int16_t t) { return v1 + ((v2 - v1) * t) / S3L_FRACTIONS_PER_UNIT; } +// TODO: change parameters in interpolation functions to S3L_Unit + +/** + Same as S3L_interpolate but with v1 = 0. Should be faster. +*/ +static inline int16_t S3L_interpolateByUnitFrom0(int16_t v2, int16_t t) +{ + return (v2 * t) / S3L_FRACTIONS_PER_UNIT; +} + typedef struct { int16_t steps; @@ -703,18 +712,21 @@ S3L_Unit S3L_correctPerspective( c >>= 4; d >>= 4; - return + S3L_Unit result = ( - a * state->a[0] - b * state->a[1] - c * state->a[2] - d ) / - ( + S3L_nonZero( ( - a * state->pointDifference[0] + - b * state->pointDifference[1] + - c * state->pointDifference[2] + a * state->pointDifference[0] + + b * state->pointDifference[1] + + c * state->pointDifference[2] ) / S3L_FRACTIONS_PER_UNIT ); + + return result < 0 ? 0 : + (result > S3L_FRACTIONS_PER_UNIT ? S3L_FRACTIONS_PER_UNIT : result); } /** @@ -820,6 +832,7 @@ void _S3L_drawFilledTriangle( S3L_PixelInfo *p) { S3L_ScreenCoord x0, y0, x1, y1, x2, y2; + S3L_Vec4 *pointTop, *pointLeft, *pointRight; S3L_mapProjectionPlaneToScreen(point0,&x0,&y0); S3L_mapProjectionPlaneToScreen(point1,&x1,&y1); @@ -846,6 +859,7 @@ void _S3L_drawFilledTriangle( {\ lPointX = x##a; lPointY = y##a;\ rPointX = x##b; rPointY = y##b;\ + pointLeft = &point##a; pointRight = &point##b;\ barycentric0 = &(p->barycentric##b);\ barycentric1 = &(p->barycentric##a);\ }\ @@ -853,6 +867,7 @@ void _S3L_drawFilledTriangle( {\ lPointX = x##b; lPointY = y##b;\ rPointX = x##a; rPointY = y##a;\ + pointLeft = &point##b; pointRight = &point##a;\ barycentric0 = &(p->barycentric##a);\ barycentric1 = &(p->barycentric##b);\ } @@ -863,6 +878,7 @@ void _S3L_drawFilledTriangle( { tPointX = x0; tPointY = y0; + pointTop = &point0; barycentric2 = &(p->barycentric0); handleLR(0,1,2) } @@ -870,6 +886,7 @@ void _S3L_drawFilledTriangle( { tPointX = x2; tPointY = y2; + pointTop = &point2; barycentric2 = &(p->barycentric2); handleLR(2,0,1) } @@ -880,6 +897,7 @@ void _S3L_drawFilledTriangle( { tPointX = x1; tPointY = y1; + pointTop = &point1; barycentric2 = &(p->barycentric1); handleLR(1,0,2) } @@ -887,6 +905,7 @@ void _S3L_drawFilledTriangle( { tPointX = x2; tPointY = y2; + pointTop = &point2; barycentric2 = &(p->barycentric2); handleLR(2,0,1) } @@ -988,6 +1007,36 @@ void _S3L_drawFilledTriangle( initSide(r,t,r,1) initSide(l,t,l,1) +#if S3L_PERSPECTIVE_CORRECTION == 1 + S3L_PerspectiveCorrectionState lPC, rPC, rowPC; + + S3L_Unit + lDepthFrom = pointTop->z, + lDepthTo = pointLeft->z, + rDepthFrom = pointTop->z, + rDepthTo = pointRight->z; + + S3L_initPerspectiveCorrectionState( + pointTop->x, + pointTop->y, + pointTop->z, + pointLeft->x, + pointLeft->y, + pointLeft->z, + camera->focalLength, + &lPC); + + S3L_initPerspectiveCorrectionState( + pointTop->x, + pointTop->y, + pointTop->z, + pointRight->x, + pointRight->y, + pointRight->z, + camera->focalLength, + &rPC); +#endif + while (currentY < endY) /* draw the triangle from top to bottom -- the bottom-most row is left out because, following from the rasterization rules (see top of the @@ -1007,6 +1056,21 @@ void _S3L_drawFilledTriangle( - rSideUnitPos; rSideUnitStep *= -1; + +#if S3L_PERSPECTIVE_CORRECTION == 1 + S3L_initPerspectiveCorrectionState( + pointLeft->x, + pointLeft->y, + pointLeft->z, + pointRight->x, + pointRight->y, + pointRight->z, + camera->focalLength, + &lPC); + + lDepthFrom = pointLeft->z; + lDepthTo = pointRight->z; +#endif } else { @@ -1020,6 +1084,21 @@ void _S3L_drawFilledTriangle( - lSideUnitPos; lSideUnitStep *= -1; + +#if S3L_PERSPECTIVE_CORRECTION == 1 + S3L_initPerspectiveCorrectionState( + pointRight->x, + pointRight->y, + pointRight->z, + pointLeft->x, + pointLeft->y, + pointLeft->z, + camera->focalLength, + &rPC); + + rDepthFrom = pointRight->z; + rDepthTo = pointLeft->z; +#endif } } @@ -1038,10 +1117,44 @@ void _S3L_drawFilledTriangle( S3L_Unit b0Step = rSideUnitPos / rowLength; S3L_Unit b1Step = lSideUnitPos / rowLength; +#if S3L_PERSPECTIVE_CORRECTION == 1 + S3L_Unit lDepth, rDepth, lT, rT; + + lT = lSideUnitPos >> S3L_LERP_QUALITY; + rT = rSideUnitPos >> S3L_LERP_QUALITY; + +printf("%d %d\n",lDepth,rDepth); + + S3L_initPerspectiveCorrectionState( + S3L_interpolateByUnit(pointTop->x,pointLeft->x,lT), + S3L_interpolateByUnit(pointTop->y,pointLeft->y,lT), + lDepth, + S3L_interpolateByUnit(pointTop->x,pointRight->x,rT), + S3L_interpolateByUnit(pointTop->y,pointRight->y,rT), + rDepth, + camera->focalLength, + &rowPC + ); + + lT = S3L_correctPerspective(lT,&lPC); + rT = S3L_correctPerspective(rT,&rPC); + + lDepth = S3L_interpolateByUnit(lDepthFrom,lDepthTo,lT); + rDepth = S3L_interpolateByUnit(rDepthFrom,rDepthTo,rT); +#endif + for (S3L_ScreenCoord x = lX; x < rX; ++x) { *barycentric0 = b0 >> S3L_LERP_QUALITY; *barycentric1 = b1 >> S3L_LERP_QUALITY; + +#if S3L_PERSPECTIVE_CORRECTION == 1 + S3L_Unit rowT = S3L_interpolateFrom0(S3L_FRACTIONS_PER_UNIT,x - lX,rX - lX); + + *barycentric0 = S3L_interpolateByUnitFrom0(lT,rowT); + *barycentric1 = S3L_interpolateByUnitFrom0(rT,S3L_FRACTIONS_PER_UNIT - rowT); +#endif + *barycentric2 = S3L_FRACTIONS_PER_UNIT - *barycentric0 - *barycentric1; p->x = x; diff --git a/testSDL.c b/testSDL.c index 4c48ca1..6bb4d6e 100644 --- a/testSDL.c +++ b/testSDL.c @@ -119,10 +119,11 @@ void draw() //frame = 853; - modelTransform.rotation.z = frame * 0.1; - modelTransform.rotation.x = frame * 0.3; +// modelTransform.rotation.z = frame * 0.1; + modelTransform.rotation.x = 60;//frame * 0.3; S3L_drawModelIndexed(ver,tri,12,modelTransform,&camera,&conf); +// S3L_drawModelIndexed(ver,tri + 3,1,modelTransform,&camera,&conf); /* conf.backfaceCulling = S3L_BACKFACE_CULLING_NONE;