diff options
Diffstat (limited to 'src/mesa/tnl/t_vb_cliptmp.h')
| -rw-r--r-- | src/mesa/tnl/t_vb_cliptmp.h | 103 |
1 files changed, 88 insertions, 15 deletions
diff --git a/src/mesa/tnl/t_vb_cliptmp.h b/src/mesa/tnl/t_vb_cliptmp.h index 618b8b3130..0d2183a9e6 100644 --- a/src/mesa/tnl/t_vb_cliptmp.h +++ b/src/mesa/tnl/t_vb_cliptmp.h @@ -80,6 +80,58 @@ do { \ } while (0) +#define POLY_USERCLIP(PLANE) \ +do { \ + if (mask & CLIP_USER_BIT) { \ + GLuint idxPrev = inlist[0]; \ + GLfloat dpPrev = VB->ClipDistancePtr[PLANE][idxPrev]; \ + GLuint outcount = 0; \ + GLuint i; \ + \ + inlist[n] = inlist[0]; /* prevent rotation of vertices */ \ + for (i = 1; i <= n; i++) { \ + GLuint idx = inlist[i]; \ + GLfloat dp = VB->ClipDistancePtr[PLANE][idx]; \ + \ + if (!IS_NEGATIVE(dpPrev)) { \ + outlist[outcount++] = idxPrev; \ + } \ + \ + if (DIFFERENT_SIGNS(dp, dpPrev)) { \ + if (IS_NEGATIVE(dp)) { \ + /* Going out of bounds. Avoid division by zero as we \ + * know dp != dpPrev from DIFFERENT_SIGNS, above. \ + */ \ + GLfloat t = dp / (dp - dpPrev); \ + INTERP_4F( t, coord[newvert], coord[idx], coord[idxPrev]); \ + interp( ctx, t, newvert, idx, idxPrev, GL_TRUE ); \ + } else { \ + /* Coming back in. \ + */ \ + GLfloat t = dpPrev / (dpPrev - dp); \ + INTERP_4F( t, coord[newvert], coord[idxPrev], coord[idx]); \ + interp( ctx, t, newvert, idxPrev, idx, GL_FALSE ); \ + } \ + outlist[outcount++] = newvert++; \ + } \ + \ + idxPrev = idx; \ + dpPrev = dp; \ + } \ + \ + if (outcount < 3) \ + return; \ + \ + { \ + GLuint *tmp = inlist; \ + inlist = outlist; \ + outlist = tmp; \ + n = outcount; \ + } \ + } \ +} while (0) + + #define LINE_CLIP(PLANE_BIT, A, B, C, D ) \ do { \ if (mask & PLANE_BIT) { \ @@ -111,6 +163,37 @@ do { \ } while (0) +#define LINE_USERCLIP(PLANE) \ +do { \ + if (mask & CLIP_USER_BIT) { \ + const GLfloat dp0 = VB->ClipDistancePtr[PLANE][v0]; \ + const GLfloat dp1 = VB->ClipDistancePtr[PLANE][v1]; \ + const GLboolean neg_dp0 = IS_NEGATIVE(dp0); \ + const GLboolean neg_dp1 = IS_NEGATIVE(dp1); \ + \ + /* For regular clipping, we know from the clipmask that one \ + * (or both) of these must be negative (otherwise we wouldn't \ + * be here). \ + * For userclip, there is only a single bit for all active \ + * planes, so we can end up here when there is nothing to do, \ + * hence the second IS_NEGATIVE() test: \ + */ \ + if (neg_dp0 && neg_dp1) \ + return; /* both vertices outside clip plane: discard */ \ + \ + if (neg_dp1) { \ + GLfloat t = dp1 / (dp1 - dp0); \ + if (t > t1) t1 = t; \ + } else if (neg_dp0) { \ + GLfloat t = dp0 / (dp0 - dp1); \ + if (t > t0) t0 = t; \ + } \ + if (t0 + t1 >= 1.0) \ + return; /* discard */ \ + } \ +} while (0) + + /* Clip a line against the viewport and user clip planes. */ @@ -139,11 +222,7 @@ TAG(clip_line)( GLcontext *ctx, GLuint v0, GLuint v1, GLubyte mask ) if (mask & CLIP_USER_BIT) { for (p = 0; p < ctx->Const.MaxClipPlanes; p++) { if (ctx->Transform.ClipPlanesEnabled & (1 << p)) { - const GLfloat a = ctx->Transform._ClipUserPlane[p][0]; - const GLfloat b = ctx->Transform._ClipUserPlane[p][1]; - const GLfloat c = ctx->Transform._ClipUserPlane[p][2]; - const GLfloat d = ctx->Transform._ClipUserPlane[p][3]; - LINE_CLIP( CLIP_USER_BIT, a, b, c, d ); + LINE_USERCLIP(p); } } } @@ -228,11 +307,7 @@ TAG(clip_tri)( GLcontext *ctx, GLuint v0, GLuint v1, GLuint v2, GLubyte mask ) if (mask & CLIP_USER_BIT) { for (p = 0; p < ctx->Const.MaxClipPlanes; p++) { if (ctx->Transform.ClipPlanesEnabled & (1 << p)) { - const GLfloat a = ctx->Transform._ClipUserPlane[p][0]; - const GLfloat b = ctx->Transform._ClipUserPlane[p][1]; - const GLfloat c = ctx->Transform._ClipUserPlane[p][2]; - const GLfloat d = ctx->Transform._ClipUserPlane[p][3]; - POLY_CLIP( CLIP_USER_BIT, a, b, c, d ); + POLY_USERCLIP(p); } } } @@ -291,11 +366,7 @@ TAG(clip_quad)( GLcontext *ctx, GLuint v0, GLuint v1, GLuint v2, GLuint v3, if (mask & CLIP_USER_BIT) { for (p = 0; p < ctx->Const.MaxClipPlanes; p++) { if (ctx->Transform.ClipPlanesEnabled & (1 << p)) { - const GLfloat a = ctx->Transform._ClipUserPlane[p][0]; - const GLfloat b = ctx->Transform._ClipUserPlane[p][1]; - const GLfloat c = ctx->Transform._ClipUserPlane[p][2]; - const GLfloat d = ctx->Transform._ClipUserPlane[p][3]; - POLY_CLIP( CLIP_USER_BIT, a, b, c, d ); + POLY_USERCLIP(p); } } } @@ -317,4 +388,6 @@ TAG(clip_quad)( GLcontext *ctx, GLuint v0, GLuint v1, GLuint v2, GLuint v3, #undef SIZE #undef TAG #undef POLY_CLIP +#undef POLY_USERCLIP #undef LINE_CLIP +#undef LINE_USERCLIP |