-
-
-
-
-/**********************************************************************/
-/* 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;
-}
-
-
-
-
-#if 0
-#define NEGATIVE(x) ((*(int *)&x)<0)
-#define DIFFERENT_SIGNS(a,b) ((a*b) < 0)
-#else
-#define NEGATIVE(x) (x < 0)
-#define DIFFERENT_SIGNS(a,b) ((a*b) < 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)
- {
- 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->Fog.Enabled)
- 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;
-}
-