quakeforge/libs/video/renderer/sw32/sw32_rsprite.c
Bill Currie 3a17e062da [renderer] Merge sprite billboarding code
As the sw renderer's implementation was the closest to id's, it was used
as the model (thus a fair bit of cleanup is still needed). This fixes
some incorrect implementations in glsl and gl.
2021-12-24 06:45:13 +09:00

301 lines
7.4 KiB
C

/*
sw32_rsprite.c
(description)
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:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#define NH_DEFINE
#include "namehack.h"
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <string.h>
#endif
#include <math.h>
#include "QF/render.h"
#include "QF/sys.h"
#include "QF/scene/entity.h"
#include "r_internal.h"
static int clip_current;
static vec5_t clip_verts[2][MAXWORKINGVERTS];
static int sprite_width, sprite_height;
spritedesc_t sw32_r_spritedesc;
static void
R_RotateSprite (float beamlength)
{
vec3_t vec;
if (beamlength == 0.0)
return;
VectorScale (sw32_r_spritedesc.vpn, -beamlength, vec);
VectorAdd (r_entorigin, vec, r_entorigin);
VectorSubtract (modelorg, vec, modelorg);
}
/*
R_ClipSpriteFace
Clips the winding at clip_verts[clip_current] and changes clip_current
Throws out the back side
*/
static int
R_ClipSpriteFace (int nump, clipplane_t *pclipplane)
{
int i, outcount;
float dists[MAXWORKINGVERTS + 1];
float frac, clipdist, *pclipnormal;
float *in, *instep, *outstep, *vert2;
clipdist = pclipplane->dist;
pclipnormal = pclipplane->normal;
// calc dists
if (clip_current) {
in = clip_verts[1][0];
outstep = clip_verts[0][0];
clip_current = 0;
} else {
in = clip_verts[0][0];
outstep = clip_verts[1][0];
clip_current = 1;
}
instep = in;
for (i = 0; i < nump; i++, instep += sizeof (vec5_t) / sizeof (float)) {
dists[i] = DotProduct (instep, pclipnormal) - clipdist;
}
// handle wraparound case
dists[nump] = dists[0];
memcpy (instep, in, sizeof (vec5_t));
// clip the winding
instep = in;
outcount = 0;
for (i = 0; i < nump; i++, instep += sizeof (vec5_t) / sizeof (float)) {
if (dists[i] >= 0) {
memcpy (outstep, instep, sizeof (vec5_t));
outstep += sizeof (vec5_t) / sizeof (float);
outcount++;
}
if (dists[i] == 0 || dists[i + 1] == 0)
continue;
if ((dists[i] > 0) == (dists[i + 1] > 0))
continue;
// split it into a new vertex
frac = dists[i] / (dists[i] - dists[i + 1]);
vert2 = instep + sizeof (vec5_t) / sizeof (float);
outstep[0] = instep[0] + frac * (vert2[0] - instep[0]);
outstep[1] = instep[1] + frac * (vert2[1] - instep[1]);
outstep[2] = instep[2] + frac * (vert2[2] - instep[2]);
outstep[3] = instep[3] + frac * (vert2[3] - instep[3]);
outstep[4] = instep[4] + frac * (vert2[4] - instep[4]);
outstep += sizeof (vec5_t) / sizeof (float);
outcount++;
}
return outcount;
}
static void
R_SetupAndDrawSprite (void)
{
int i, nump;
float dot, scale, *pv;
vec5_t *pverts;
vec3_t left, up, right, down, transformed, local;
emitpoint_t outverts[MAXWORKINGVERTS + 1], *pout;
dot = DotProduct (sw32_r_spritedesc.vpn, modelorg);
// backface cull
if (dot >= 0)
return;
// build the sprite poster in worldspace
VectorScale (sw32_r_spritedesc.vright, sw32_r_spritedesc.pspriteframe->right, right);
VectorScale (sw32_r_spritedesc.vup, sw32_r_spritedesc.pspriteframe->up, up);
VectorScale (sw32_r_spritedesc.vright, sw32_r_spritedesc.pspriteframe->left, left);
VectorScale (sw32_r_spritedesc.vup, sw32_r_spritedesc.pspriteframe->down, down);
pverts = clip_verts[0];
pverts[0][0] = r_entorigin[0] + up[0] + left[0];
pverts[0][1] = r_entorigin[1] + up[1] + left[1];
pverts[0][2] = r_entorigin[2] + up[2] + left[2];
pverts[0][3] = 0;
pverts[0][4] = 0;
pverts[1][0] = r_entorigin[0] + up[0] + right[0];
pverts[1][1] = r_entorigin[1] + up[1] + right[1];
pverts[1][2] = r_entorigin[2] + up[2] + right[2];
pverts[1][3] = sprite_width;
pverts[1][4] = 0;
pverts[2][0] = r_entorigin[0] + down[0] + right[0];
pverts[2][1] = r_entorigin[1] + down[1] + right[1];
pverts[2][2] = r_entorigin[2] + down[2] + right[2];
pverts[2][3] = sprite_width;
pverts[2][4] = sprite_height;
pverts[3][0] = r_entorigin[0] + down[0] + left[0];
pverts[3][1] = r_entorigin[1] + down[1] + left[1];
pverts[3][2] = r_entorigin[2] + down[2] + left[2];
pverts[3][3] = 0;
pverts[3][4] = sprite_height;
// clip to the frustum in worldspace
nump = 4;
clip_current = 0;
for (i = 0; i < 4; i++) {
nump = R_ClipSpriteFace (nump, &sw32_view_clipplanes[i]);
if (nump < 3)
return;
if (nump >= MAXWORKINGVERTS)
Sys_Error ("R_SetupAndDrawSprite: too many points");
}
// transform vertices into viewspace and project
pv = &clip_verts[clip_current][0][0];
sw32_r_spritedesc.nearzi = -999999;
for (i = 0; i < nump; i++) {
VectorSubtract (pv, r_origin, local);
sw32_TransformVector (local, transformed);
if (transformed[2] < NEAR_CLIP)
transformed[2] = NEAR_CLIP;
pout = &outverts[i];
pout->zi = 1.0 / transformed[2];
if (pout->zi > sw32_r_spritedesc.nearzi)
sw32_r_spritedesc.nearzi = pout->zi;
pout->s = pv[3];
pout->t = pv[4];
scale = sw32_xscale * pout->zi;
pout->u = (sw32_xcenter + scale * transformed[0]);
scale = sw32_yscale * pout->zi;
pout->v = (sw32_ycenter - scale * transformed[1]);
pv += sizeof (vec5_t) / sizeof (*pv);
}
// draw it
sw32_r_spritedesc.nump = nump;
sw32_r_spritedesc.pverts = outverts;
sw32_D_DrawSprite ();
}
static mspriteframe_t *
R_GetSpriteframe (msprite_t *psprite)
{
mspritegroup_t *pspritegroup;
mspriteframe_t *pspriteframe;
int i, numframes, frame;
float *pintervals, fullinterval, targettime, time;
frame = currententity->animation.frame;
if ((frame >= psprite->numframes) || (frame < 0)) {
Sys_Printf ("R_DrawSprite: no such frame %d\n", frame);
frame = 0;
}
if (psprite->frames[frame].type == SPR_SINGLE) {
pspriteframe = psprite->frames[frame].frameptr;
} else {
pspritegroup = (mspritegroup_t *) psprite->frames[frame].frameptr;
pintervals = pspritegroup->intervals;
numframes = pspritegroup->numframes;
fullinterval = pintervals[numframes - 1];
time = vr_data.realtime + currententity->animation.syncbase;
// when loading in Mod_LoadSpriteGroup, we guaranteed all interval
// values are positive, so we don't have to worry about division by 0
targettime = time - ((int) (time / fullinterval)) * fullinterval;
for (i = 0; i < (numframes - 1); i++) {
if (pintervals[i] > targettime)
break;
}
pspriteframe = pspritegroup->frames[i];
}
return pspriteframe;
}
void
sw32_R_DrawSprite (void)
{
msprite_t *sprite = currententity->renderer.model->cache.data;
sw32_r_spritedesc.pspriteframe = R_GetSpriteframe (sprite);
sprite_width = sw32_r_spritedesc.pspriteframe->width;
sprite_height = sw32_r_spritedesc.pspriteframe->height;
if (!R_BillboardFrame (currententity, sprite->type, modelorg,
r_spritedesc.vup,
r_spritedesc.vright,
r_spritedesc.vpn)) {
// the orientation is undefined so can't draw the sprite
return;
}
R_RotateSprite (sprite->beamlength);
R_SetupAndDrawSprite ();
}