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Minor transformation adjustments to try to keep scenery tiles closer to

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(0, 0, 0)  GLfloats run out of precision at the distances we need to model
the earth, but we can do a bunch of pre-transformations using double math
and then cast to GLfloat once everything is close in where we have less
precision problems.
This commit is contained in:
curt 1998-04-27 03:30:13 +00:00
parent 4a487175c9
commit ed0acbad5b
2 changed files with 35 additions and 14 deletions
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30
Scenery/obj.c
View file

@ -95,7 +95,7 @@ float calc_lat(double x, double y, double z) {
GLint fgObjLoad(char *path, struct fgCartesianPoint *ref, double *radius) { GLint fgObjLoad(char *path, struct fgCartesianPoint *ref, double *radius) {
char gzpath[256], line[256], winding_str[256]; char gzpath[256], line[256], winding_str[256];
double approx_normal[3], normal[3], scale; double approx_normal[3], normal[3], scale;
double x, y, z, xmax, xmin, ymax, ymin, zmax, zmin; // double x, y, z, xmax, xmin, ymax, ymin, zmax, zmin;
GLfloat sgenparams[] = { 1.0, 0.0, 0.0, 0.0 }; GLfloat sgenparams[] = { 1.0, 0.0, 0.0, 0.0 };
GLint tile; GLint tile;
gzFile f; gzFile f;
@ -143,16 +143,18 @@ GLint fgObjLoad(char *path, struct fgCartesianPoint *ref, double *radius) {
/* comment -- ignore */ /* comment -- ignore */
} else if ( line[0] == '\n' ) { } else if ( line[0] == '\n' ) {
/* empty line -- ignore */ /* empty line -- ignore */
} else if ( strncmp(line, "ref ", 4) == 0 ) {
/* reference point (center offset) */
sscanf(line, "ref %lf %lf %lf\n", &ref->x, &ref->y, &ref->z);
} else if ( strncmp(line, "v ", 2) == 0 ) { } else if ( strncmp(line, "v ", 2) == 0 ) {
/* node (vertex) */ /* node (vertex) */
if ( ncount < MAXNODES ) { if ( ncount < MAXNODES ) {
/* fgPrintf( FG_TERRAIN, FG_DEBUG, "vertex = %s", line); */ /* fgPrintf( FG_TERRAIN, FG_DEBUG, "vertex = %s", line); */
sscanf(line, "v %lf %lf %lf\n", &x, &y, &z); sscanf(line, "v %lf %lf %lf\n",
nodes[ncount][0] = x; &nodes[ncount][0], &nodes[ncount][1], &nodes[ncount][2]);
nodes[ncount][1] = y;
nodes[ncount][2] = z;
/* first time through set min's and max'es */ /* first time through set min's and max'es */
/*
if ( ncount == 1 ) { if ( ncount == 1 ) {
xmin = x; xmin = x;
xmax = x; xmax = x;
@ -161,14 +163,17 @@ GLint fgObjLoad(char *path, struct fgCartesianPoint *ref, double *radius) {
zmin = z; zmin = z;
zmax = z; zmax = z;
} }
*/
/* keep track of min/max vertex values */ /* keep track of min/max vertex values */
/*
if ( x < xmin ) xmin = x; if ( x < xmin ) xmin = x;
if ( x > xmax ) xmax = x; if ( x > xmax ) xmax = x;
if ( y < ymin ) ymin = y; if ( y < ymin ) ymin = y;
if ( y > ymax ) ymax = y; if ( y > ymax ) ymax = y;
if ( z < zmin ) zmin = z; if ( z < zmin ) zmin = z;
if ( z > zmax ) zmax = z; if ( z > zmax ) zmax = z;
*/
ncount++; ncount++;
} else { } else {
@ -395,19 +400,28 @@ GLint fgObjLoad(char *path, struct fgCartesianPoint *ref, double *radius) {
gzclose(f); gzclose(f);
/* reference point is the "center" */ /* reference point is the "center" (now included in input file) */
/*
ref->x = (xmin + xmax) / 2.0; ref->x = (xmin + xmax) / 2.0;
ref->y = (ymin + ymax) / 2.0; ref->y = (ymin + ymax) / 2.0;
ref->z = (zmin + zmax) / 2.0; ref->z = (zmin + zmax) / 2.0;
*/
return(tile); return(tile);
} }
/* $Log$ /* $Log$
/* Revision 1.31 1998/04/25 15:09:57 curt /* Revision 1.32 1998/04/27 03:30:13 curt
/* Changed "r" to "rb" in gzopen() options. This fixes bad behavior in win32. /* Minor transformation adjustments to try to keep scenery tiles closer to
/* (0, 0, 0) GLfloats run out of precision at the distances we need to model
/* the earth, but we can do a bunch of pre-transformations using double math
/* and then cast to GLfloat once everything is close in where we have less
/* precision problems.
/* /*
* Revision 1.31 1998/04/25 15:09:57 curt
* Changed "r" to "rb" in gzopen() options. This fixes bad behavior in win32.
*
* Revision 1.30 1998/04/24 14:21:08 curt * Revision 1.30 1998/04/24 14:21:08 curt
* Added "file.obj.gz" support. * Added "file.obj.gz" support.
* *

19
Scenery/tilemgr.cxx
View file

@ -208,11 +208,11 @@ void fgTileMgrRender( void ) {
if ( display_list >= 0 ) { if ( display_list >= 0 ) {
xglPushMatrix(); xglPushMatrix();
/* xglTranslatef(local_ref.x - scenery.center.x, xglTranslatef(local_ref.x - scenery.center.x,
local_ref.y - scenery.center.y, local_ref.y - scenery.center.y,
local_ref.z - scenery.center.z); */ local_ref.z - scenery.center.z);
xglTranslatef(-scenery.center.x, -scenery.center.y, /* xglTranslatef(-scenery.center.x, -scenery.center.y,
-scenery.center.z); -scenery.center.z); */
xglCallList(display_list); xglCallList(display_list);
xglPopMatrix(); xglPopMatrix();
} }
@ -221,9 +221,16 @@ void fgTileMgrRender( void ) {
/* $Log$ /* $Log$
/* Revision 1.3 1998/04/25 22:06:32 curt /* Revision 1.4 1998/04/27 03:30:14 curt
/* Edited cvs log messages in source files ... bad bad bad! /* Minor transformation adjustments to try to keep scenery tiles closer to
/* (0, 0, 0) GLfloats run out of precision at the distances we need to model
/* the earth, but we can do a bunch of pre-transformations using double math
/* and then cast to GLfloat once everything is close in where we have less
/* precision problems.
/* /*
* Revision 1.3 1998/04/25 22:06:32 curt
* Edited cvs log messages in source files ... bad bad bad!
*
* Revision 1.2 1998/04/24 00:51:09 curt * Revision 1.2 1998/04/24 00:51:09 curt
* Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H" * Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
* Tweaked the scenery file extentions to be "file.obj" (uncompressed) * Tweaked the scenery file extentions to be "file.obj" (uncompressed)