quakeforge-old/uquake/r_aclip.c
Jeff Teunissen c3f5581b0a Created new subdir: uquake. Pick your favorite U word for the meaning --
Unchained, Ultimate, Ultra, Up Yours, Underworld, Underground, Unified,
Unity, etc. You know the drill.

This takes care of the "standalone" problem with the wrong name, and the
recent snafu with multiple developers working on the same files
simultaneously...expect me (and probably others) to start locking dirs when
updates are taking place.

And yes, this update is really as large as it looks. Software only at the
moment, but I will have the makefile updated to build the GL builds as
well.
1999-12-26 13:51:52 +00:00

350 lines
8.2 KiB
C

/*
Copyright (C) 1996-1997 Id Software, Inc.
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
// r_aclip.c: clip routines for drawing Alias models directly to the screen
#include "quakedef.h"
#include "r_local.h"
#include "d_local.h"
static finalvert_t fv[2][8];
static auxvert_t av[8];
void R_AliasProjectFinalVert (finalvert_t *fv, auxvert_t *av);
void R_Alias_clip_top (finalvert_t *pfv0, finalvert_t *pfv1,
finalvert_t *out);
void R_Alias_clip_bottom (finalvert_t *pfv0, finalvert_t *pfv1,
finalvert_t *out);
void R_Alias_clip_left (finalvert_t *pfv0, finalvert_t *pfv1,
finalvert_t *out);
void R_Alias_clip_right (finalvert_t *pfv0, finalvert_t *pfv1,
finalvert_t *out);
/*
================
R_Alias_clip_z
pfv0 is the unclipped vertex, pfv1 is the z-clipped vertex
================
*/
void R_Alias_clip_z (finalvert_t *pfv0, finalvert_t *pfv1, finalvert_t *out)
{
float scale;
auxvert_t *pav0, *pav1, avout;
pav0 = &av[pfv0 - &fv[0][0]];
pav1 = &av[pfv1 - &fv[0][0]];
if (pfv0->v[1] >= pfv1->v[1])
{
scale = (ALIAS_Z_CLIP_PLANE - pav0->fv[2]) /
(pav1->fv[2] - pav0->fv[2]);
avout.fv[0] = pav0->fv[0] + (pav1->fv[0] - pav0->fv[0]) * scale;
avout.fv[1] = pav0->fv[1] + (pav1->fv[1] - pav0->fv[1]) * scale;
avout.fv[2] = ALIAS_Z_CLIP_PLANE;
out->v[2] = pfv0->v[2] + (pfv1->v[2] - pfv0->v[2]) * scale;
out->v[3] = pfv0->v[3] + (pfv1->v[3] - pfv0->v[3]) * scale;
out->v[4] = pfv0->v[4] + (pfv1->v[4] - pfv0->v[4]) * scale;
}
else
{
scale = (ALIAS_Z_CLIP_PLANE - pav1->fv[2]) /
(pav0->fv[2] - pav1->fv[2]);
avout.fv[0] = pav1->fv[0] + (pav0->fv[0] - pav1->fv[0]) * scale;
avout.fv[1] = pav1->fv[1] + (pav0->fv[1] - pav1->fv[1]) * scale;
avout.fv[2] = ALIAS_Z_CLIP_PLANE;
out->v[2] = pfv1->v[2] + (pfv0->v[2] - pfv1->v[2]) * scale;
out->v[3] = pfv1->v[3] + (pfv0->v[3] - pfv1->v[3]) * scale;
out->v[4] = pfv1->v[4] + (pfv0->v[4] - pfv1->v[4]) * scale;
}
R_AliasProjectFinalVert (out, &avout);
if (out->v[0] < r_refdef.aliasvrect.x)
out->flags |= ALIAS_LEFT_CLIP;
if (out->v[1] < r_refdef.aliasvrect.y)
out->flags |= ALIAS_TOP_CLIP;
if (out->v[0] > r_refdef.aliasvrectright)
out->flags |= ALIAS_RIGHT_CLIP;
if (out->v[1] > r_refdef.aliasvrectbottom)
out->flags |= ALIAS_BOTTOM_CLIP;
}
#if !id386
void R_Alias_clip_left (finalvert_t *pfv0, finalvert_t *pfv1, finalvert_t *out)
{
float scale;
int i;
if (pfv0->v[1] >= pfv1->v[1])
{
scale = (float)(r_refdef.aliasvrect.x - pfv0->v[0]) /
(pfv1->v[0] - pfv0->v[0]);
for (i=0 ; i<6 ; i++)
out->v[i] = pfv0->v[i] + (pfv1->v[i] - pfv0->v[i])*scale + 0.5;
}
else
{
scale = (float)(r_refdef.aliasvrect.x - pfv1->v[0]) /
(pfv0->v[0] - pfv1->v[0]);
for (i=0 ; i<6 ; i++)
out->v[i] = pfv1->v[i] + (pfv0->v[i] - pfv1->v[i])*scale + 0.5;
}
}
void R_Alias_clip_right (finalvert_t *pfv0, finalvert_t *pfv1,
finalvert_t *out)
{
float scale;
int i;
if (pfv0->v[1] >= pfv1->v[1])
{
scale = (float)(r_refdef.aliasvrectright - pfv0->v[0]) /
(pfv1->v[0] - pfv0->v[0]);
for (i=0 ; i<6 ; i++)
out->v[i] = pfv0->v[i] + (pfv1->v[i] - pfv0->v[i])*scale + 0.5;
}
else
{
scale = (float)(r_refdef.aliasvrectright - pfv1->v[0]) /
(pfv0->v[0] - pfv1->v[0]);
for (i=0 ; i<6 ; i++)
out->v[i] = pfv1->v[i] + (pfv0->v[i] - pfv1->v[i])*scale + 0.5;
}
}
void R_Alias_clip_top (finalvert_t *pfv0, finalvert_t *pfv1, finalvert_t *out)
{
float scale;
int i;
if (pfv0->v[1] >= pfv1->v[1])
{
scale = (float)(r_refdef.aliasvrect.y - pfv0->v[1]) /
(pfv1->v[1] - pfv0->v[1]);
for (i=0 ; i<6 ; i++)
out->v[i] = pfv0->v[i] + (pfv1->v[i] - pfv0->v[i])*scale + 0.5;
}
else
{
scale = (float)(r_refdef.aliasvrect.y - pfv1->v[1]) /
(pfv0->v[1] - pfv1->v[1]);
for (i=0 ; i<6 ; i++)
out->v[i] = pfv1->v[i] + (pfv0->v[i] - pfv1->v[i])*scale + 0.5;
}
}
void R_Alias_clip_bottom (finalvert_t *pfv0, finalvert_t *pfv1,
finalvert_t *out)
{
float scale;
int i;
if (pfv0->v[1] >= pfv1->v[1])
{
scale = (float)(r_refdef.aliasvrectbottom - pfv0->v[1]) /
(pfv1->v[1] - pfv0->v[1]);
for (i=0 ; i<6 ; i++)
out->v[i] = pfv0->v[i] + (pfv1->v[i] - pfv0->v[i])*scale + 0.5;
}
else
{
scale = (float)(r_refdef.aliasvrectbottom - pfv1->v[1]) /
(pfv0->v[1] - pfv1->v[1]);
for (i=0 ; i<6 ; i++)
out->v[i] = pfv1->v[i] + (pfv0->v[i] - pfv1->v[i])*scale + 0.5;
}
}
#endif
int R_AliasClip (finalvert_t *in, finalvert_t *out, int flag, int count,
void(*clip)(finalvert_t *pfv0, finalvert_t *pfv1, finalvert_t *out) )
{
int i,j,k;
int flags, oldflags;
j = count-1;
k = 0;
for (i=0 ; i<count ; j = i, i++)
{
oldflags = in[j].flags & flag;
flags = in[i].flags & flag;
if (flags && oldflags)
continue;
if (oldflags ^ flags)
{
clip (&in[j], &in[i], &out[k]);
out[k].flags = 0;
if (out[k].v[0] < r_refdef.aliasvrect.x)
out[k].flags |= ALIAS_LEFT_CLIP;
if (out[k].v[1] < r_refdef.aliasvrect.y)
out[k].flags |= ALIAS_TOP_CLIP;
if (out[k].v[0] > r_refdef.aliasvrectright)
out[k].flags |= ALIAS_RIGHT_CLIP;
if (out[k].v[1] > r_refdef.aliasvrectbottom)
out[k].flags |= ALIAS_BOTTOM_CLIP;
k++;
}
if (!flags)
{
out[k] = in[i];
k++;
}
}
return k;
}
/*
================
R_AliasClipTriangle
================
*/
void R_AliasClipTriangle (mtriangle_t *ptri)
{
int i, k, pingpong;
mtriangle_t mtri;
unsigned clipflags;
// copy vertexes and fix seam texture coordinates
if (ptri->facesfront)
{
fv[0][0] = pfinalverts[ptri->vertindex[0]];
fv[0][1] = pfinalverts[ptri->vertindex[1]];
fv[0][2] = pfinalverts[ptri->vertindex[2]];
}
else
{
for (i=0 ; i<3 ; i++)
{
fv[0][i] = pfinalverts[ptri->vertindex[i]];
if (!ptri->facesfront && (fv[0][i].flags & ALIAS_ONSEAM) )
fv[0][i].v[2] += r_affinetridesc.seamfixupX16;
}
}
// clip
clipflags = fv[0][0].flags | fv[0][1].flags | fv[0][2].flags;
if (clipflags & ALIAS_Z_CLIP)
{
for (i=0 ; i<3 ; i++)
av[i] = pauxverts[ptri->vertindex[i]];
k = R_AliasClip (fv[0], fv[1], ALIAS_Z_CLIP, 3, R_Alias_clip_z);
if (k == 0)
return;
pingpong = 1;
clipflags = fv[1][0].flags | fv[1][1].flags | fv[1][2].flags;
}
else
{
pingpong = 0;
k = 3;
}
if (clipflags & ALIAS_LEFT_CLIP)
{
k = R_AliasClip (fv[pingpong], fv[pingpong ^ 1],
ALIAS_LEFT_CLIP, k, R_Alias_clip_left);
if (k == 0)
return;
pingpong ^= 1;
}
if (clipflags & ALIAS_RIGHT_CLIP)
{
k = R_AliasClip (fv[pingpong], fv[pingpong ^ 1],
ALIAS_RIGHT_CLIP, k, R_Alias_clip_right);
if (k == 0)
return;
pingpong ^= 1;
}
if (clipflags & ALIAS_BOTTOM_CLIP)
{
k = R_AliasClip (fv[pingpong], fv[pingpong ^ 1],
ALIAS_BOTTOM_CLIP, k, R_Alias_clip_bottom);
if (k == 0)
return;
pingpong ^= 1;
}
if (clipflags & ALIAS_TOP_CLIP)
{
k = R_AliasClip (fv[pingpong], fv[pingpong ^ 1],
ALIAS_TOP_CLIP, k, R_Alias_clip_top);
if (k == 0)
return;
pingpong ^= 1;
}
for (i=0 ; i<k ; i++)
{
if (fv[pingpong][i].v[0] < r_refdef.aliasvrect.x)
fv[pingpong][i].v[0] = r_refdef.aliasvrect.x;
else if (fv[pingpong][i].v[0] > r_refdef.aliasvrectright)
fv[pingpong][i].v[0] = r_refdef.aliasvrectright;
if (fv[pingpong][i].v[1] < r_refdef.aliasvrect.y)
fv[pingpong][i].v[1] = r_refdef.aliasvrect.y;
else if (fv[pingpong][i].v[1] > r_refdef.aliasvrectbottom)
fv[pingpong][i].v[1] = r_refdef.aliasvrectbottom;
fv[pingpong][i].flags = 0;
}
// draw triangles
mtri.facesfront = ptri->facesfront;
r_affinetridesc.ptriangles = &mtri;
r_affinetridesc.pfinalverts = fv[pingpong];
// FIXME: do all at once as trifan?
mtri.vertindex[0] = 0;
for (i=1 ; i<k-1 ; i++)
{
mtri.vertindex[1] = i;
mtri.vertindex[2] = i+1;
D_PolysetDraw ();
}
}