/* $Id: clip.c,v 1.3 2000-05-23 20:40:25 jeroen Exp $ */ /* * Mesa 3-D graphics library * Version: 3.3 * * Copyright (C) 1999 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. */ #ifdef PC_HEADER #include "all.h" #else #include "glheader.h" #include "clip.h" #include "types.h" #include "context.h" #include "macros.h" #include "matrix.h" #include "mmath.h" #include "vb.h" #include "xform.h" #endif #define CLIP_RGBA0 0x1 #define CLIP_RGBA1 0x2 #define CLIP_TEX0 0x4 #define CLIP_TEX1 0x8 #define CLIP_INDEX0 0x10 #define CLIP_INDEX1 0x20 #define CLIP_FOG_COORD 0x40 /* Linear interpolation between A and B: */ #define LINTERP( T, A, B ) ( (A) + (T) * ( (B) - (A) ) ) #define INTERP_SZ( t, vec, to, a, b, sz ) \ do { \ switch (sz) { \ case 4: vec[to][3] = LINTERP( t, vec[a][3], vec[b][3] ); \ case 3: vec[to][2] = LINTERP( t, vec[a][2], vec[b][2] ); \ case 2: vec[to][1] = LINTERP( t, vec[a][1], vec[b][1] ); \ case 1: vec[to][0] = LINTERP( t, vec[a][0], vec[b][0] ); \ } \ } while(0) static clip_interp_func clip_interp_tab[0x80]; #define IND 0 #define NAME clip_nil #include "interp_tmp.h" #define IND (CLIP_RGBA0) #define NAME clipRGBA0 #include "interp_tmp.h" #define IND (CLIP_RGBA0|CLIP_RGBA1) #define NAME clipRGBA0_RGBA1 #include "interp_tmp.h" #define IND (CLIP_TEX0|CLIP_RGBA0) #define NAME clipTEX0_RGBA0 #include "interp_tmp.h" #define IND (CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1) #define NAME clipTEX0_RGBA0_RGBA1 #include "interp_tmp.h" #define IND (CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0) #define NAME clipTEX1_TEX0_RGBA0 #include "interp_tmp.h" #define IND (CLIP_TEX0) #define NAME clipTEX0 #include "interp_tmp.h" #define IND (CLIP_TEX1|CLIP_TEX0) #define NAME clipTEX1_TEX0 #include "interp_tmp.h" #define IND (CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1) #define NAME clipTEX1_TEX0_RGBA0_RGBA1 #include "interp_tmp.h" #define IND (CLIP_INDEX0) #define NAME clipINDEX0 #include "interp_tmp.h" #define IND (CLIP_INDEX0|CLIP_INDEX1) #define NAME clipINDEX0_INDEX1 #include "interp_tmp.h" #define IND (CLIP_FOG_COORD) #define NAME clip_FOG #include "interp_tmp.h" #define IND (CLIP_RGBA0|CLIP_FOG_COORD) #define NAME clipRGBA0_FOG #include "interp_tmp.h" #define IND (CLIP_RGBA0|CLIP_RGBA1|CLIP_FOG_COORD) #define NAME clipRGBA0_RGBA1_FOG #include "interp_tmp.h" #define IND (CLIP_TEX0|CLIP_RGBA0|CLIP_FOG_COORD) #define NAME clipTEX0_RGBA0_FOG #include "interp_tmp.h" #define IND (CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1|CLIP_FOG_COORD) #define NAME clipTEX0_RGBA0_RGBA1_FOG #include "interp_tmp.h" #define IND (CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0|CLIP_FOG_COORD) #define NAME clipTEX1_TEX0_RGBA0_FOG #include "interp_tmp.h" #define IND (CLIP_TEX0|CLIP_FOG_COORD) #define NAME clipTEX0_FOG #include "interp_tmp.h" #define IND (CLIP_TEX1|CLIP_TEX0|CLIP_FOG_COORD) #define NAME clipTEX1_TEX0_FOG #include "interp_tmp.h" #define IND (CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1|CLIP_FOG_COORD) #define NAME clipTEX1_TEX0_RGBA0_RGBA1_FOG #include "interp_tmp.h" #define IND (CLIP_INDEX0|CLIP_FOG_COORD) #define NAME clipINDEX0_FOG #include "interp_tmp.h" #define IND (CLIP_INDEX0|CLIP_INDEX1|CLIP_FOG_COORD) #define NAME clipINDEX0_INDEX1_FOG #include "interp_tmp.h" /**********************************************************************/ /* Get/Set User clip-planes. */ /**********************************************************************/ void _mesa_ClipPlane( GLenum plane, const GLdouble *eq ) { GET_CURRENT_CONTEXT(ctx); GLint p; GLfloat equation[4]; equation[0] = eq[0]; equation[1] = eq[1]; equation[2] = eq[2]; equation[3] = eq[3]; ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glClipPlane"); p = (GLint) plane - (GLint) GL_CLIP_PLANE0; if (p<0 || p>=MAX_CLIP_PLANES) { gl_error( ctx, GL_INVALID_ENUM, "glClipPlane" ); return; } /* * The equation is transformed by the transpose of the inverse of the * current modelview matrix and stored in the resulting eye coordinates. * * KW: Eqn is then transformed to the current clip space, where user * clipping now takes place. The clip-space equations are recalculated * whenever the projection matrix changes. */ if (ctx->ModelView.flags & MAT_DIRTY_ALL_OVER) { gl_matrix_analyze( &ctx->ModelView ); } gl_transform_vector( ctx->Transform.EyeUserPlane[p], equation, ctx->ModelView.inv ); if (ctx->Transform.ClipEnabled[p]) { ctx->NewState |= NEW_USER_CLIP; if (ctx->ProjectionMatrix.flags & MAT_DIRTY_ALL_OVER) { gl_matrix_analyze( &ctx->ProjectionMatrix ); } gl_transform_vector( ctx->Transform.ClipUserPlane[p], ctx->Transform.EyeUserPlane[p], ctx->ProjectionMatrix.inv ); } } void gl_update_userclip( GLcontext *ctx ) { GLuint p; for (p = 0 ; p < MAX_CLIP_PLANES ; p++) { if (ctx->Transform.ClipEnabled[p]) { gl_transform_vector( ctx->Transform.ClipUserPlane[p], ctx->Transform.EyeUserPlane[p], ctx->ProjectionMatrix.inv ); } } } void _mesa_GetClipPlane( GLenum plane, GLdouble *equation ) { GET_CURRENT_CONTEXT(ctx); GLint p; ASSERT_OUTSIDE_BEGIN_END(ctx, "glGetClipPlane"); p = (GLint) (plane - GL_CLIP_PLANE0); if (p<0 || p>=MAX_CLIP_PLANES) { gl_error( ctx, GL_INVALID_ENUM, "glGetClipPlane" ); return; } equation[0] = (GLdouble) ctx->Transform.EyeUserPlane[p][0]; equation[1] = (GLdouble) ctx->Transform.EyeUserPlane[p][1]; equation[2] = (GLdouble) ctx->Transform.EyeUserPlane[p][2]; equation[3] = (GLdouble) ctx->Transform.EyeUserPlane[p][3]; } /**********************************************************************/ /* View volume clipping. */ /**********************************************************************/ /* * Clip a point against the view volume. * Input: v - vertex-vector describing the point to clip * Return: 0 = outside view volume * 1 = inside view volume */ GLuint gl_viewclip_point( const GLfloat v[] ) { if ( v[0] > v[3] || v[0] < -v[3] || v[1] > v[3] || v[1] < -v[3] || v[2] > v[3] || v[2] < -v[3] ) { return 0; } else { return 1; } } /* * Clip a point against the user clipping planes. * Input: v - vertex-vector describing the point to clip. * Return: 0 = point was clipped * 1 = point not clipped */ GLuint gl_userclip_point( GLcontext* ctx, const GLfloat v[] ) { GLuint p; for (p=0;pTransform.ClipEnabled[p]) { GLfloat dot = v[0] * ctx->Transform.ClipUserPlane[p][0] + v[1] * ctx->Transform.ClipUserPlane[p][1] + v[2] * ctx->Transform.ClipUserPlane[p][2] + v[3] * ctx->Transform.ClipUserPlane[p][3]; if (dot < 0.0F) { return 0; } } } return 1; } #if defined(__i386__) #define NEGATIVE(x) ((*(int *)&x)<0) #else #define NEGATIVE(x) (x < 0) #endif static clip_poly_func gl_poly_clip_tab[2][5]; static clip_line_func gl_line_clip_tab[2][5]; #define W(i) coord[i][3] #define Z(i) coord[i][2] #define Y(i) coord[i][1] #define X(i) coord[i][0] #define SIZE 4 #define IND 0 #define TAG(x) x##_4 #include "clip_funcs.h" #define W(i) 1.0 #define Z(i) coord[i][2] #define Y(i) coord[i][1] #define X(i) coord[i][0] #define SIZE 3 #define IND 0 #define TAG(x) x##_3 #include "clip_funcs.h" #define W(i) 1.0 #define Z(i) 0.0 #define Y(i) coord[i][1] #define X(i) coord[i][0] #define SIZE 2 #define IND 0 #define TAG(x) x##_2 #include "clip_funcs.h" #define W(i) coord[i][3] #define Z(i) coord[i][2] #define Y(i) coord[i][1] #define X(i) coord[i][0] #define SIZE 4 #define IND CLIP_TAB_EDGEFLAG #define TAG(x) x##_4_edgeflag #include "clip_funcs.h" #define W(i) 1.0 #define Z(i) coord[i][2] #define Y(i) coord[i][1] #define X(i) coord[i][0] #define SIZE 3 #define IND CLIP_TAB_EDGEFLAG #define TAG(x) x##_3_edgeflag #include "clip_funcs.h" #define W(i) 1.0 #define Z(i) 0.0 #define Y(i) coord[i][1] #define X(i) coord[i][0] #define SIZE 2 #define IND CLIP_TAB_EDGEFLAG #define TAG(x) x##_2_edgeflag #include "clip_funcs.h" void gl_update_clipmask( GLcontext *ctx ) { GLuint mask = 0; if (ctx->Visual->RGBAflag) { if (ctx->Light.ShadeModel==GL_SMOOTH) { mask |= CLIP_RGBA0; if (ctx->TriangleCaps & (DD_TRI_LIGHT_TWOSIDE|DD_SEPERATE_SPECULAR)) mask |= CLIP_RGBA1; } if (ctx->Texture.ReallyEnabled & 0xf0) mask |= CLIP_TEX1|CLIP_TEX0; if (ctx->Texture.ReallyEnabled & 0xf) mask |= CLIP_TEX0; } else if (ctx->Light.ShadeModel==GL_SMOOTH) { mask |= CLIP_INDEX0; if (ctx->TriangleCaps & DD_TRI_LIGHT_TWOSIDE) mask |= CLIP_INDEX1; } if (ctx->FogMode == FOG_FRAGMENT && (ctx->TriangleCaps & DD_CLIP_FOG_COORD)) mask |= CLIP_FOG_COORD; ctx->ClipInterpFunc = clip_interp_tab[mask]; ctx->poly_clip_tab = gl_poly_clip_tab[0]; ctx->line_clip_tab = gl_line_clip_tab[0]; if (ctx->TriangleCaps & DD_TRI_UNFILLED) { ctx->poly_clip_tab = gl_poly_clip_tab[1]; ctx->line_clip_tab = gl_line_clip_tab[0]; } } #define USER_CLIPTEST(NAME, SZ) \ static void NAME( struct vertex_buffer *VB ) \ { \ GLcontext *ctx = VB->ctx; \ GLubyte *clipMask = VB->ClipMask; \ GLubyte *userClipMask = VB->UserClipMask; \ GLuint start = VB->Start; \ GLuint count = VB->Count; \ GLuint p, i; \ GLubyte bit; \ \ \ for (bit = 1, p = 0; p < MAX_CLIP_PLANES ; p++, bit *=2) \ if (ctx->Transform.ClipEnabled[p]) { \ GLuint nr = 0; \ 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]; \ GLfloat *coord = VB->ClipPtr->start; \ GLuint stride = VB->ClipPtr->stride; \ \ for (i = start ; i < count ; i++, STRIDE_F(coord, stride)) { \ GLfloat dp = coord[0] * a + coord[1] * b; \ if (SZ > 2) dp += coord[2] * c; \ if (SZ > 3) dp += coord[3] * d; else dp += d; \ \ if (dp < 0) { \ clipMask[i] |= CLIP_USER_BIT; \ userClipMask[i] |= bit; \ nr++; \ } \ } \ \ if (nr > 0) { \ VB->ClipOrMask |= CLIP_USER_BIT; \ VB->CullMode |= CLIP_MASK_ACTIVE; \ if (nr == count - start) { \ VB->ClipAndMask |= CLIP_USER_BIT; \ VB->Culled = 1; \ return; \ } \ } \ } \ } USER_CLIPTEST(userclip2, 2) USER_CLIPTEST(userclip3, 3) USER_CLIPTEST(userclip4, 4) static void (*(usercliptab[5]))( struct vertex_buffer * ) = { 0, 0, userclip2, userclip3, userclip4 }; void gl_user_cliptest( struct vertex_buffer *VB ) { usercliptab[VB->ClipPtr->size]( VB ); } void gl_init_clip(void) { init_clip_funcs_4(); init_clip_funcs_3(); init_clip_funcs_2(); init_clip_funcs_4_edgeflag(); init_clip_funcs_3_edgeflag(); init_clip_funcs_2_edgeflag(); clip_interp_tab[0] = clip_nil; clip_interp_tab[CLIP_RGBA0] = clipRGBA0; clip_interp_tab[CLIP_RGBA0|CLIP_RGBA1] = clipRGBA0_RGBA1; clip_interp_tab[CLIP_TEX0|CLIP_RGBA0] = clipTEX0_RGBA0; clip_interp_tab[CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1] = clipTEX0_RGBA0_RGBA1; clip_interp_tab[CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0] = clipTEX1_TEX0_RGBA0; clip_interp_tab[CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1] = clipTEX1_TEX0_RGBA0_RGBA1; clip_interp_tab[CLIP_TEX0] = clipTEX0; clip_interp_tab[CLIP_TEX1|CLIP_TEX0] = clipTEX1_TEX0; clip_interp_tab[CLIP_INDEX0] = clipINDEX0; clip_interp_tab[CLIP_INDEX0|CLIP_INDEX1] = clipINDEX0_INDEX1; clip_interp_tab[CLIP_FOG_COORD] = clip_FOG; clip_interp_tab[CLIP_RGBA0|CLIP_FOG_COORD] = clipRGBA0_FOG; clip_interp_tab[CLIP_RGBA0|CLIP_RGBA1|CLIP_FOG_COORD] = clipRGBA0_RGBA1_FOG; clip_interp_tab[CLIP_TEX0|CLIP_RGBA0|CLIP_FOG_COORD] = clipTEX0_RGBA0_FOG; clip_interp_tab[CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1|CLIP_FOG_COORD] = clipTEX0_RGBA0_RGBA1_FOG; clip_interp_tab[CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0|CLIP_FOG_COORD] = clipTEX1_TEX0_RGBA0_FOG; clip_interp_tab[CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1|CLIP_FOG_COORD] = clipTEX1_TEX0_RGBA0_RGBA1_FOG; clip_interp_tab[CLIP_TEX0|CLIP_FOG_COORD] = clipTEX0_FOG; clip_interp_tab[CLIP_TEX1|CLIP_TEX0|CLIP_FOG_COORD] = clipTEX1_TEX0_FOG; clip_interp_tab[CLIP_INDEX0|CLIP_FOG_COORD] = clipINDEX0_FOG; clip_interp_tab[CLIP_INDEX0|CLIP_INDEX1|CLIP_FOG_COORD] = clipINDEX0_INDEX1_FOG; }