diff options
Diffstat (limited to 'src/mesa/swrast')
| -rw-r--r-- | src/mesa/swrast/s_texture.c | 74 |
1 files changed, 57 insertions, 17 deletions
diff --git a/src/mesa/swrast/s_texture.c b/src/mesa/swrast/s_texture.c index 10349e4ced1..220d3a43660 100644 --- a/src/mesa/swrast/s_texture.c +++ b/src/mesa/swrast/s_texture.c @@ -1,4 +1,4 @@ -/* $Id: s_texture.c,v 1.19 2001/03/23 18:53:26 brianp Exp $ */ +/* $Id: s_texture.c,v 1.20 2001/03/26 19:42:40 brianp Exp $ */ /* * Mesa 3-D graphics library @@ -46,6 +46,11 @@ #define GL_DOT3_RGBA_ARB 0x86AF #endif +/* XXX this is temporary, until GL/glext.h is updated. */ +#ifndef GL_CLAMP_TO_BORDER_ARB +#define GL_CLAMP_TO_BORDER_ARB 0x812D +#endif + /* * These values are used in the fixed-point arithmetic used @@ -58,7 +63,7 @@ /* * Used to compute texel locations for linear sampling. * Input: - * wrapMode = GL_REPEAT, GL_CLAMP or GL_CLAMP_TO_EDGE + * wrapMode = GL_REPEAT, GL_CLAMP, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_BORDER_ARB * S = texcoord in [0,1] * SIZE = width (or height or depth) of texture * Output: @@ -72,22 +77,45 @@ I0 = IFLOOR(U) & (SIZE - 1); \ I1 = (I0 + 1) & (SIZE - 1); \ } \ + else if (wrapMode == GL_CLAMP_TO_EDGE) { \ + if (S <= 0.0F) \ + U = 0.0F; \ + else if (S >= 1.0F) \ + U = SIZE; \ + else \ + U = S * SIZE; \ + U -= 0.5F; \ + I0 = IFLOOR(U); \ + I1 = I0 + 1; \ + if (I0 < 0) \ + I0 = 0; \ + if (I1 >= (GLint) SIZE) \ + I1 = SIZE - 1; \ + } \ + else if (wrapMode == GL_CLAMP_TO_BORDER_ARB) { \ + const GLfloat min = -1.0F / (2.0F * SIZE); \ + const GLfloat max = 1.0F - min; \ + if (S <= min) \ + U = min * SIZE; \ + else if (S >= max) \ + U = max * SIZE; \ + else \ + U = S * SIZE; \ + U -= 0.5F; \ + I0 = IFLOOR(U); \ + I1 = I0 + 1; \ + } \ else { \ + ASSERT(wrapMode == GL_CLAMP); \ if (S <= 0.0F) \ U = 0.0F; \ else if (S >= 1.0F) \ U = SIZE; \ - else \ - U = S * SIZE; \ + else \ + U = S * SIZE; \ U -= 0.5F; \ I0 = IFLOOR(U); \ I1 = I0 + 1; \ - if (wrapMode == GL_CLAMP_TO_EDGE) { \ - if (I0 < 0) \ - I0 = 0; \ - if (I1 >= (GLint) SIZE) \ - I1 = SIZE - 1; \ - } \ } \ } @@ -99,13 +127,13 @@ { \ if (wrapMode == GL_REPEAT) { \ /* s limited to [0,1) */ \ - /* i limited to [0,width-1] */ \ - I = (GLint) (S * SIZE); \ - if (S < 0.0F) \ - I -= 1; \ + /* i limited to [0,size-1] */ \ + I = IFLOOR(S * SIZE); \ I &= (SIZE - 1); \ } \ else if (wrapMode == GL_CLAMP_TO_EDGE) { \ + /* s limited to [min,max] */ \ + /* i limited to [0, size-1] */ \ const GLfloat min = 1.0F / (2.0F * SIZE); \ const GLfloat max = 1.0F - min; \ if (S < min) \ @@ -113,18 +141,30 @@ else if (S > max) \ I = SIZE - 1; \ else \ - I = (GLint) (S * SIZE); \ + I = IFLOOR(S * SIZE); \ + } \ + else if (wrapMode == GL_CLAMP_TO_BORDER_ARB) { \ + /* s limited to [min,max] */ \ + /* i limited to [-1, size] */ \ + const GLfloat min = -1.0F / (2.0F * SIZE); \ + const GLfloat max = 1.0F - min; \ + if (S <= min) \ + I = -1; \ + else if (S >= max) \ + I = SIZE; \ + else \ + I = IFLOOR(S * SIZE); \ } \ else { \ ASSERT(wrapMode == GL_CLAMP); \ /* s limited to [0,1] */ \ - /* i limited to [0,width-1] */ \ + /* i limited to [0,size-1] */ \ if (S <= 0.0F) \ I = 0; \ else if (S >= 1.0F) \ I = SIZE - 1; \ else \ - I = (GLint) (S * SIZE); \ + I = IFLOOR(S * SIZE); \ } \ } |