fly/flightgear
1
0
Fork 0
Code Activity

Tweaking vertex orders.

Browse source
This commit is contained in:
curt 1997-10-31 04:49:12 +00:00
parent b5293f1f44
commit 62872fb302
1 changed files with 61 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

67
Scenery/obj.c
View file

@ -37,6 +37,7 @@
#include "../constants.h"
#include "../types.h"
#include "../Math/fg_geodesy.h"
#include "../Math/mat3.h"
#include "../Math/polar.h"
@ -68,14 +69,33 @@ struct fgCartesianPoint geod_to_cart(float geod[3]) {
}
/* given three points defining a triangle, calculate the normal */
void calc_normal(struct fgCartesianPoint p1, struct fgCartesianPoint p2,
struct fgCartesianPoint p3, double normal[3])
{
double v1[3], v2[3];
float temp;
v1[0] = p2.x - p1.x; v1[1] = p2.y - p1.y; v1[2] = p2.z - p1.z;
v2[0] = p3.x - p1.x; v2[1] = p3.y - p1.y; v2[2] = p3.z - p1.z;
MAT3cross_product(normal, v1, v2);
MAT3_NORMALIZE_VEC(normal,temp);
printf("Normal = %.2f %.2f %.2f\n", normal[0], normal[1], normal[2]);
}
/* Load a .obj file and generate the GL call list */
GLint fgObjLoad(char *path) {
char line[256];
static GLfloat color[4] = { 0.5, 0.5, 0.25, 1.0 };
struct fgCartesianPoint p1, p2, p3, p4, ref;
struct fgCartesianPoint p1, p2, p3, p4, ref, last1, last2;
GLint area;
FILE *f;
double normal[3];
int first, ncount, n1, n2, n3, n4;
int toggle = 0;
if ( (f = fopen(path, "r")) == NULL ) {
printf("Cannot open file: %s\n", path);
@ -116,6 +136,7 @@ GLint fgObjLoad(char *path) {
/* start a new triangle strip */
n1 = n2 = n3 = n4 = 0;
toggle = 0;
if ( !first ) {
/* close out the previous structure and start the next */
@ -126,21 +147,32 @@ GLint fgObjLoad(char *path) {
}
printf("new tri strip = %s", line);
sscanf(line, "t %d %d %d\n", &n1, &n2, &n3);
sscanf(line, "t %d %d %d %d\n", &n1, &n2, &n3, &n4);
p1 = geod_to_cart(nodes[n1]);
p2 = geod_to_cart(nodes[n2]);
p3 = geod_to_cart(nodes[n3]);
glNormal3d(0.0, 0.0, -1.0);
printf("(t) = ");
calc_normal(p1, p2, p3, normal);
glNormal3d(normal[0], normal[1], normal[2]);
glVertex3d(p1.x - ref.x, p1.y - ref.y, p1.z - ref.z);
glVertex3d(p2.x - ref.x, p2.y - ref.y, p2.z - ref.z);
glVertex3d(p3.x - ref.x, p3.y - ref.y, p3.z - ref.z);
last1 = p2;
last2 = p3;
if ( n4 > 0 ) {
p4 = geod_to_cart(nodes[n4]);
printf("(t) cont = ");
calc_normal(last2, last1, p4, normal);
glNormal3d(normal[0], normal[1], normal[2]);
glVertex3d(p4.x - ref.x, p4.y - ref.y, p4.z - ref.z);
last1 = last2;
last2 = p4;
toggle = 1 - toggle;
}
} else if ( line[0] == 'q' ) {
/* continue a triangle strip */
@ -151,11 +183,31 @@ GLint fgObjLoad(char *path) {
printf("read %d %d\n", n1, n2);
p1 = geod_to_cart(nodes[n1]);
printf("(q) = ");
if ( toggle ) {
calc_normal(last1, last2, p1, normal);
} else {
calc_normal(last1, p1, last2, normal);
}
glNormal3d(normal[0], normal[1], normal[2]);
glVertex3d(p1.x - ref.x, p1.y - ref.y, p1.z - ref.z);
last1 = last2;
last2 = p1;
toggle = 1 - toggle;
if ( n2 > 0 ) {
p2 = geod_to_cart(nodes[n2]);
printf("(q) cont = ");
calc_normal(last1, last2, p2, normal);
glNormal3d(normal[0], normal[1], normal[2]);
glVertex3d(p2.x - ref.x, p2.y - ref.y, p2.z - ref.z);
last1 = last2;
last2 = p2;
toggle = 1 - toggle;
}
} else {
printf("Unknown line in %s = %s\n", path, line);
@ -172,9 +224,12 @@ GLint fgObjLoad(char *path) {
/* $Log$
/* Revision 1.2 1997/10/30 12:38:45 curt
/* Working on new scenery subsystem.
/* Revision 1.3 1997/10/31 04:49:12 curt
/* Tweaking vertex orders.
/*
* Revision 1.2 1997/10/30 12:38:45 curt
* Working on new scenery subsystem.
*
* Revision 1.1 1997/10/28 21:14:54 curt
* Initial revision.
*