This is imagetext.c in view mode; [Download] [Up]
/*
* imagetext.c
*
* Copyright (C) 1989, 1991, Craig E. Kolb
* All rights reserved.
*
* This software may be freely copied, modified, and redistributed
* provided that this copyright notice is preserved on all copies.
*
* You may not distribute this software, in whole or in part, as part of
* any commercial product without the express consent of the authors.
*
* There is no warranty or other guarantee of fitness of this software
* for any purpose. It is provided solely "as is".
*
* $Id$
*
* $Log$
*/
#include "texture.h"
#include "libimage/image.h"
#include "imagetext.h"
#define INTERP(v) (text->lo + (v)*(text->hi - text->lo))
/*
* Create Image texture.
* Image texture has so many options that there's usually no
* nice way to parse without resorting to additional keywords.
* Thus the ImageTextCreate routine only reads the image to be used;
* all but ->component must be set by hand. The routine
* ImageTextSetComponent is provided to set the component and
* ensure that the image being used is appropriate.
*/
ImageText *
ImageTextCreate(imagefile)
char *imagefile;
{
ImageText *text;
text = (ImageText *)Calloc(1, sizeof(ImageText));
text->component = COLOR; /* texture all colors by default*/
/*
* Only apply one copy of the texture by default
*/
text->tileu = text->tilev = 0;
text->mapping = UVMappingCreate();
text->image = ImageRead(imagefile);
return text;
}
/*
* Set image texture to apply to given component,
* ensuring that the image that is being used is compatible.
*/
void
ImageTextSetComponent(text, component)
ImageText *text;
int component;
{
switch (component) {
case COLOR: /* usual case, texture on amb, diff, spec */
case AMBIENT:
case DIFFUSE:
case SPECULAR:
/* all of the above can use 1 or 3 channel images */
if (text->image->chan != 1 && text->image->chan != 3) {
RLerror(RL_ABORT,
"Image %s must have 1 or 3 channels\n",
text->image->filename);
}
break;
case SPECPOW:
case REFLECT:
case TRANSP:
case BUMP:
/* the above need 1 channel images */
if (text->image->chan != 1) {
RLerror(RL_ABORT, "Image %s must have 1 channel\n",
text->image->filename);
}
break;
}
text->component = component;
}
void
ImageTextApply(text, prim, ray, pos, norm, gnorm, surf)
ImageText *text;
Object *prim;
Ray *ray;
Vector *pos, *norm, *gnorm;
Surface *surf;
{
Float fx, fy;
Float outval[4], outval_u[4], outval_v[4];
Float u, v;
Surface tmpsurf;
int ix, iy;
int rchan, gchan, bchan;
Vector dpdu, dpdv, ntmp;
/*
* First, find the floating point location in image coords.
* Then set ix, iy to the integer location in image coords and
* use fx, fy to represent the subpixel position.
*/
if (text->component == BUMP)
TextToUV(text->mapping, prim, pos, gnorm, &u, &v,
&dpdu, &dpdv);
else
TextToUV(text->mapping, prim, pos, gnorm, &u, &v,
(Vector *)NULL, (Vector *)NULL);
/*
* Handle tiling at this point.
*/
if (TileValue(text->tileu, text->tilev, u, v))
return;
u -= floor(u);
v -= floor(v);
fx = u * (Float) text->image->width;
fy = v * (Float) text->image->height;
ix = fx;
iy = fy;
fx = fx - (Float) ix;
fy = fy - (Float) iy;
if (text->image->has_alpha) {
/* Alpha channel is 0 */
rchan = 1;
gchan = 2;
bchan = 3;
} else {
rchan = 0;
gchan = 1;
bchan = 2;
}
if (text->image->chan == 1) {
gchan = rchan;
bchan = rchan;
}
ImageIndex(text->image, ix, iy, fx, fy, text->smooth, outval);
/*
* escape when alpha is zero, 'cause there is no change
*/
if (text->image->has_alpha && (outval[0] < 0.001))
return;
if (text->component != COLOR || text->surf == (Surface *)NULL) {
tmpsurf = *surf;
} else {
tmpsurf = *text->surf;
}
switch (text->component) {
case COLOR: /* amb, diff, spec */
tmpsurf.spec.r *= outval[rchan];
tmpsurf.spec.g *= outval[gchan];
tmpsurf.spec.b *= outval[bchan];
tmpsurf.diff.r *= outval[rchan];
tmpsurf.diff.g *= outval[gchan];
tmpsurf.diff.b *= outval[bchan];
tmpsurf.amb.r *= outval[rchan];
tmpsurf.amb.g *= outval[gchan];
tmpsurf.amb.b *= outval[bchan];
break;
case AMBIENT: /* ambient */
tmpsurf.amb.r = INTERP(outval[rchan]);
tmpsurf.amb.g = INTERP(outval[gchan]);
tmpsurf.amb.b = INTERP(outval[bchan]);
break;
case DIFFUSE: /* diffuse */
tmpsurf.diff.r = INTERP(outval[rchan]);
tmpsurf.diff.g = INTERP(outval[gchan]);
tmpsurf.diff.b = INTERP(outval[bchan]);
break;
case SPECULAR: /* specular */
tmpsurf.spec.r = INTERP(outval[rchan]);
tmpsurf.spec.g = INTERP(outval[gchan]);
tmpsurf.spec.b = INTERP(outval[bchan]);
break;
case SPECPOW: /* specpow */
tmpsurf.coef = INTERP(outval[rchan]);
break;
case REFLECT: /* reflect */
tmpsurf.refl = INTERP(outval[rchan]);
break;
case TRANSP: /* refract */
tmpsurf.transp = INTERP(outval[rchan]);
break;
case BUMP: /* bump map */
ImageIndex(text->image,
(ix == text->image->width - 1) ? 0 : ix+1,
iy, fx, fy,
text->smooth, outval_u);
ImageIndex(text->image, ix,
(iy == text->image->height - 1) ? 0 : iy+1,
fx, fy,
text->smooth, outval_v);
MakeBump(norm, &dpdu, &dpdv,
INTERP(outval_u[rchan] - outval[rchan]),
INTERP(outval_v[rchan] - outval[rchan]));
return;
}
if (text->image->has_alpha && (outval[0] < 0.999)) {
/*
* image partial coverage means blend surf and text->surf
*/
SurfaceBlend(surf, &tmpsurf, 1. - outval[0], outval[0]);
} else {
/*
* image full coverage means use text->surf
*/
*surf = tmpsurf;
}
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.