Initial revision

1 files changed, 460 insertions, 0 deletions

diff --git a/src/mesa/main/clip.c b/src/mesa/main/clip.c
new file mode 100644
index 00000000000..9feaf2472ea
--- /dev/null
+++ b/src/mesa/main/clip.c
@@ -0,0 +1,460 @@
+/* $Id: clip.c,v 1.1 1999/08/19 00:55:41 jtg Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version:  3.1
+ * 
+ * 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 <string.h>
+#include <stdlib.h>
+#include "clip.h"
+#include "context.h"
+#include "macros.h"
+#include "matrix.h"
+#include "mmath.h"
+#include "types.h"
+#include "vb.h"
+#include "xform.h"
+#ifdef XFree86Server
+#include "GL/xf86glx.h"
+#endif
+#endif
+
+
+
+
+/* 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)
+   
+
+
+
+#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_EDGE     0x40
+
+/* This is sparsely populated: */
+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_RGBA0|CLIP_EDGE)
+#define NAME clipRGBA0_EDGE
+#include "interp_tmp.h"
+
+#define IND (CLIP_RGBA0|CLIP_RGBA1|CLIP_EDGE)
+#define NAME clipRGBA0_RGBA1_EDGE
+#include "interp_tmp.h"
+
+#define IND (CLIP_TEX0|CLIP_RGBA0|CLIP_EDGE)
+#define NAME clipTEX0_RGBA0_EDGE
+#include "interp_tmp.h"
+
+#define IND (CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1|CLIP_EDGE)
+#define NAME clipTEX0_RGBA0_RGBA1_EDGE
+#include "interp_tmp.h"
+
+#define IND (CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0|CLIP_EDGE)
+#define NAME clipTEX1_TEX0_RGBA0_EDGE
+#include "interp_tmp.h"
+
+#define IND (CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1|CLIP_EDGE)
+#define NAME clipTEX1_TEX0_RGBA0_RGBA1_EDGE
+#include "interp_tmp.h"
+
+#define IND (CLIP_INDEX0|CLIP_EDGE)
+#define NAME clipINDEX0_EDGE
+#include "interp_tmp.h"
+
+#define IND (CLIP_INDEX0|CLIP_INDEX1|CLIP_EDGE)
+#define NAME clipINDEX0_INDEX1_EDGE
+#include "interp_tmp.h"
+
+
+
+
+/**********************************************************************/
+/*                     Get/Set User clip-planes.                      */
+/**********************************************************************/
+
+
+
+void gl_ClipPlane( GLcontext* ctx, GLenum plane, const GLfloat *equation )
+{
+   GLint p;
+
+   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 gl_GetClipPlane( GLcontext* ctx, GLenum plane, GLdouble *equation )
+{
+   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;p<MAX_CLIP_PLANES;p++) {
+      if (ctx->Transform.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;
+}
+
+
+
+
+clip_poly_func gl_poly_clip_tab[5];
+clip_line_func gl_line_clip_tab[5];
+
+
+#if defined(__i386__)
+#define NEGATIVE(x) ((*(int *)&x)<0)
+#else
+#define NEGATIVE(x) (x < 0)
+#endif
+
+#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 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 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 TAG(x) x##_2
+#include "clip_funcs.h"
+
+#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 );
+}
+
+
+
+static clip_interp_func get_interp_func( 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;
+   }
+
+   
+   return clip_interp_tab[mask];
+}
+
+
+void gl_update_clipmask( GLcontext *ctx )
+{
+   ctx->ClipInterpFunc = get_interp_func( ctx );
+}
+
+void gl_init_clip(void)
+{
+   init_clip_funcs_4();
+   init_clip_funcs_3();
+   init_clip_funcs_2();
+
+   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_RGBA0|CLIP_EDGE] = clipRGBA0_EDGE;
+   clip_interp_tab[CLIP_RGBA0|CLIP_RGBA1|CLIP_EDGE] = clipRGBA0_RGBA1_EDGE;
+   clip_interp_tab[CLIP_TEX0|CLIP_RGBA0|CLIP_EDGE] = clipTEX0_RGBA0_EDGE;
+   clip_interp_tab[CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1|CLIP_EDGE] = clipTEX0_RGBA0_RGBA1_EDGE;
+   clip_interp_tab[CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0|CLIP_EDGE] = clipTEX1_TEX0_RGBA0_EDGE;
+   clip_interp_tab[CLIP_TEX1|CLIP_TEX0|CLIP_RGBA0|CLIP_RGBA1|CLIP_EDGE] = clipTEX1_TEX0_RGBA0_RGBA1_EDGE;
+   clip_interp_tab[CLIP_INDEX0|CLIP_EDGE] = clipINDEX0_EDGE;
+   clip_interp_tab[CLIP_INDEX0|CLIP_INDEX1|CLIP_EDGE] = clipINDEX0_INDEX1_EDGE;
+}
+