diff options
Diffstat (limited to 'src/mesa/tnl_dd/imm/t_dd_imm_vb.c')
| -rw-r--r-- | src/mesa/tnl_dd/imm/t_dd_imm_vb.c | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/src/mesa/tnl_dd/imm/t_dd_imm_vb.c b/src/mesa/tnl_dd/imm/t_dd_imm_vb.c new file mode 100644 index 0000000000..0c4462f556 --- /dev/null +++ b/src/mesa/tnl_dd/imm/t_dd_imm_vb.c @@ -0,0 +1,204 @@ + +/* + * Mesa 3-D graphics library + * Version: 3.5 + * + * Copyright (C) 1999-2001 Brian Paul All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN + * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * Authors: + * Keith Whitwell <keith_whitwell@yahoo.com> + */ + +/* Template to build clipping routines to support t_dd_imm_primtmp.h. + * + * The TAG(draw_line) and TAG(draw_triangle) routines are called in + * clipping and fallback scenarios, and when the native hardware + * primitive (eg polygons) is unavailable. + */ + + +#define CLIP_DOTPROD(K, A, B, C, D) \ + (CLIP_X(K)*A + CLIP_Y(K)*B + \ + CLIP_Z(K)*C + CLIP_W(K)*D) + +#define POLY_CLIP( PLANE, A, B, C, D ) \ +do { \ + if (mask & PLANE) { \ + TNL_VERTEX **indata = inlist[in]; \ + TNL_VERTEX **outdata = inlist[in ^= 1]; \ + TNL_VERTEX *J = indata[0]; \ + GLfloat dpJ = CLIP_DOTPROD(J, A, B, C, D ); \ + GLuint outcount = 0; \ + GLuint i; \ + \ + indata[n] = indata[0]; /* prevent rotation of vertices */ \ + for (i = 1; i <= n; i++) { \ + TNL_VERTEX *I = indata[i]; \ + GLfloat dpI = CLIP_DOTPROD(idx, A, B, C, D ); \ + \ + if (!NEGATIVE(dpPrev)) { \ + outdata[outcount++] = J; \ + } \ + \ + if (DIFFERENT_SIGNS(dpI, dpJ)) { \ + TNL_VERTEX *O = verts++; \ + outdata[outcount++] = O; \ + if (NEGATIVE(dpI)) { \ + /* Going out of bounds. Avoid division by zero as we \ + * know dp != dpPrev from DIFFERENT_SIGNS, above. \ + */ \ + GLfloat t = dpI / (dpI - dpJ); \ + INTERP( ctx, t, O, I, J ); \ + } else { \ + /* Coming back in. \ + */ \ + GLfloat t = dpJ / (dpJ - dpI); \ + INTERP( ctx, t, O, J, I ); \ + } \ + } \ + \ + J = I; \ + dpJ = dpI; \ + } \ + \ + if (outcount < 3) \ + return; \ + \ + nr = outcount; \ + } \ +} while (0) + + +#define LINE_CLIP(PLANE, A, B, C, D ) \ +do { \ + if (mask & PLANE) { \ + GLfloat dpI = CLIP_DOTPROD( I, A, B, C, D ); \ + GLfloat dpJ = CLIP_DOTPROD( J, A, B, C, D ); \ + \ + if (DIFFERENT_SIGNS(dpI, dpJ)) { \ + TNL_VERTEX *O = verts++; \ + if (NEGATIVE(dpJ)) { \ + GLfloat t = dpI / (dpI - dpJ); \ + INTERP( ctx, t, O, I, J ); \ + J = O; \ + } else { \ + GLfloat t = dpJ / (dpJ - dpI); \ + INTERP( ctx, t, O, J, I ); \ + I = O; \ + } \ + } \ + else if (NEGATIVE(dpI)) \ + return; \ + } \ +} while (0) + + + +/* Clip a line against the viewport and user clip planes. + */ +static void TAG(clip_draw_line)( GLcontext *ctx, + TNL_VERTEX *I, + TNL_VERTEX *J, + GLuint mask ) +{ + LOCAL_VARS; + GET_INTERP_FUNC; + TNL_VERTEX tmp[MAX_CLIPPED_VERTICES]; + TNL_VERTEX *verts = tmp; + TNL_VERTEX *pv = J; + + LINE_CLIP( CLIP_RIGHT_BIT, -1, 0, 0, 1 ); + LINE_CLIP( CLIP_LEFT_BIT, 1, 0, 0, 1 ); + LINE_CLIP( CLIP_TOP_BIT, 0, -1, 0, 1 ); + LINE_CLIP( CLIP_BOTTOM_BIT, 0, 1, 0, 1 ); + LINE_CLIP( CLIP_FAR_BIT, 0, 0, -1, 1 ); + LINE_CLIP( CLIP_NEAR_BIT, 0, 0, 1, 1 ); + + if ((ctx->_TriangleCaps & DD_FLATSHADE) && J != pv) + COPY_PV( ctx, J, pv ); + + DRAW_LINE( I, J ); +} + + +/* Clip a triangle against the viewport and user clip planes. + */ +static void TAG(clip_draw_triangle)( GLcontext *ctx, + TNL_VERTEX *v0, + TNL_VERTEX *v1, + TNL_VERTEX *v2, + GLuint mask ) +{ + LOCAL_VARS; + GET_INTERP_FUNC; + TNL_VERTEX tmp[MAX_CLIPPED_VERTICES]; + TNL_VERTEX *verts = tmp; + TNL_VERTEX *(inlist[2][MAX_CLIPPED_VERTICES]); + TNL_VERTEX **out; + GLuint in = 0; + GLuint n = 3; + GLuint i; + + ASSIGN_3V(inlist, v2, v0, v1 ); /* pv rotated to slot zero */ + + POLY_CLIP( CLIP_RIGHT_BIT, -1, 0, 0, 1 ); + POLY_CLIP( CLIP_LEFT_BIT, 1, 0, 0, 1 ); + POLY_CLIP( CLIP_TOP_BIT, 0, -1, 0, 1 ); + POLY_CLIP( CLIP_BOTTOM_BIT, 0, 1, 0, 1 ); + POLY_CLIP( CLIP_FAR_BIT, 0, 0, -1, 1 ); + POLY_CLIP( CLIP_NEAR_BIT, 0, 0, 1, 1 ); + + if ((ctx->_TriangleCaps & DD_FLATSHADE) && v2 != inlist[0]) + COPY_PV( ctx, inlist[0], v2 ); + + out = inlist[in]; + DRAW_POLYGON( out, n ); +} + + +static __inline void TAG(draw_triangle)( GLcontext *ctx, + TNL_VERTEX *v0, + TNL_VERTEX *v1, + TNL_VERTEX *v2 ) +{ + LOCAL_VARS; + GLubyte ormask = (v0->mask | v1->mask | v2->mask); + + if ( !ormask ) { + DRAW_TRI( v0, v1, v2 ); + } else if ( !(v0->mask & v1->mask & v2->mask) ) { + TAG(clip_draw_triangle)( ctx, v0, v1, v2, ormask ); + } +} + +static __inline void TAG(draw_line)( GLcontext *ctx, + TNL_VERTEX *v0, + TNL_VERTEX *v1 ) +{ + LOCAL_VARS; + GLubyte ormask = (v0->mask | v1->mask); + + if ( !ormask ) { + DRAW_LINE( v0, v1 ); + } else if ( !(v0->mask & v1->mask) ) { + TAG(clip_draw_line)( ctx, v0, v1, ormask ); + } +} + |