#endif
#include <stdio.h>
+#include <string.h>
#include <GL/glut.h>
#include "obj.h"
#include "scenery.h"
-#include "../constants.h"
-#include "../types.h"
-#include "../Math/fg_geodesy.h"
#include "../Math/mat3.h"
-#include "../Math/polar.h"
+
#define MAXNODES 100000
float nodes[MAXNODES][3];
-
-
-/* convert a geodetic point lon(arcsec), lat(arcsec), elev(meter) to
- * a cartesian point */
-struct fgCartesianPoint geod_to_cart(float geod[3]) {
- struct fgCartesianPoint p;
- double gc_lon, gc_lat, sl_radius;
-
- /* printf("A geodetic point is (%.2f, %.2f, %.2f)\n",
- geod[0], geod[1], geod[2]); */
-
- gc_lon = geod[0]*ARCSEC_TO_RAD;
- fgGeodToGeoc(geod[1]*ARCSEC_TO_RAD, geod[2], &sl_radius, &gc_lat);
-
- /* printf("A geocentric point is (%.2f, %.2f, %.2f)\n", gc_lon,
- gc_lat, sl_radius+geod[2]); */
-
- p = fgPolarToCart(gc_lon, gc_lat, sl_radius+geod[2]);
-
- /* printf("A cart point is (%.8f, %.8f, %.8f)\n", p.x, p.y, p.z); */
-
- return(p);
-}
-
-
-/* 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]);
-}
+float normals[MAXNODES][3];
/* 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, last1, last2;
+ double v1[3], v2[3], approx_normal[3], dot_prod, temp;
+ struct fgCartesianPoint ref;
GLint area;
FILE *f;
- double normal[3];
- int first, ncount, n1, n2, n3, n4;
- int toggle = 0;
+ int first, ncount, vncount, n1, n2, n3, n4;
if ( (f = fopen(path, "r")) == NULL ) {
printf("Cannot open file: %s\n", path);
/* glMaterialfv( GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color ); */
glColor3fv(color);
- glBegin(GL_TRIANGLE_STRIP);
-
first = 1;
ncount = 1;
+ vncount = 1;
while ( fgets(line, 250, f) != NULL ) {
if ( line[0] == '#' ) {
/* comment -- ignore */
- } else if ( line[0] == 'v' ) {
+ } else if ( strncmp(line, "v ", 2) == 0 ) {
/* node (vertex) */
if ( ncount < MAXNODES ) {
/* printf("vertex = %s", line); */
&nodes[ncount][0], &nodes[ncount][1], &nodes[ncount][2]);
if ( ncount == 1 ) {
/* first node becomes the reference point */
- ref = geod_to_cart(nodes[ncount]);
+ ref.x = nodes[ncount][0];
+ ref.y = nodes[ncount][1];
+ ref.z = nodes[ncount][2];
scenery.center = ref;
}
ncount++;
printf("Read too many nodes ... dying :-(\n");
exit(-1);
}
+ } else if ( strncmp(line, "vn ", 3) == 0 ) {
+ /* vertex normal */
+ if ( vncount < MAXNODES ) {
+ /* printf("vertex normal = %s", line); */
+ sscanf(line, "vn %f %f %f\n",
+ &normals[vncount][0], &normals[vncount][1],
+ &normals[vncount][2]);
+ vncount++;
+ } else {
+ printf("Read too many vertex normals ... dying :-(\n");
+ exit(-1);
+ }
} else if ( line[0] == 't' ) {
/* start a new triangle strip */
n1 = n2 = n3 = n4 = 0;
- toggle = 0;
if ( !first ) {
/* close out the previous structure and start the next */
glEnd();
- glBegin(GL_TRIANGLE_STRIP);
} else {
first = 0;
}
+ glBegin(GL_TRIANGLE_STRIP);
+
printf("new tri strip = %s", line);
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]);
-
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;
+ /* try to get the proper rotation by calculating an
+ * approximate normal and seeing if it is close to the
+ * precalculated normal */
+ v1[0] = nodes[n2][0] - nodes[n1][0];
+ v1[1] = nodes[n2][1] - nodes[n1][1];
+ v1[2] = nodes[n2][2] - nodes[n1][2];
+ v2[0] = nodes[n3][0] - nodes[n1][0];
+ v2[1] = nodes[n3][1] - nodes[n1][1];
+ v2[2] = nodes[n3][2] - nodes[n1][2];
+ MAT3cross_product(approx_normal, v1, v2);
+ MAT3_NORMALIZE_VEC(approx_normal,temp);
+ printf("Approx normal = %.2f %.2f %.2f\n", approx_normal[0],
+ approx_normal[1], approx_normal[2]);
+ dot_prod = MAT3_DOT_PRODUCT(normals[n1], approx_normal);
+ printf("Dot product = %.4f\n", dot_prod);
+ /* angle = acos(dot_prod); */
+ /* printf("Normal ANGLE = %.3f rads.\n", angle); */
+
+ glNormal3d(normals[n1][0], normals[n1][1], normals[n1][2]);
+ glVertex3d(nodes[n1][0] - ref.x, nodes[n1][1] - ref.y,
+ nodes[n1][2] - ref.z);
+
+ if ( dot_prod > 0 ) {
+ glNormal3d(normals[n2][0], normals[n2][1], normals[n2][2]);
+ glVertex3d(nodes[n2][0] - ref.x, nodes[n2][1] - ref.y,
+ nodes[n2][2] - ref.z);
+
+ glNormal3d(normals[n3][0], normals[n3][1], normals[n3][2]);
+ glVertex3d(nodes[n3][0] - ref.x, nodes[n3][1] - ref.y,
+ nodes[n3][2] - ref.z);
+ } else {
+ printf("Reversing\n");
+ glNormal3d(normals[n3][0], normals[n3][1], normals[n3][2]);
+ glVertex3d(nodes[n3][0] - ref.x, nodes[n3][1] - ref.y,
+ nodes[n3][2] - ref.z);
+
+ glNormal3d(normals[n2][0], normals[n2][1], normals[n2][2]);
+ glVertex3d(nodes[n2][0] - ref.x, nodes[n2][1] - ref.y,
+ nodes[n2][2] - ref.z);
+ }
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;
+ glNormal3d(normals[n4][0], normals[n4][1], normals[n4][2]);
+ glVertex3d(nodes[n4][0] - ref.x, nodes[n4][1] - ref.y,
+ nodes[n4][2] - ref.z);
}
+ } else if ( line[0] == 'f' ) {
+ /* unoptimized face */
+
+ if ( !first ) {
+ /* close out the previous structure and start the next */
+ glEnd();
+ } else {
+ first = 0;
+ }
+
+ glBegin(GL_TRIANGLES);
+
+ printf("new triangle = %s", line);
+ sscanf(line, "f %d %d %d\n", &n1, &n2, &n3);
+
+ glNormal3d(normals[n1][0], normals[n1][1], normals[n1][2]);
+ glVertex3d(nodes[n1][0] - ref.x, nodes[n1][1] - ref.y,
+ nodes[n1][2] - ref.z);
+
+ glNormal3d(normals[n2][0], normals[n2][1], normals[n2][2]);
+ glVertex3d(nodes[n2][0] - ref.x, nodes[n2][1] - ref.y,
+ nodes[n2][2] - ref.z);
+
+ glNormal3d(normals[n3][0], normals[n3][1], normals[n3][2]);
+ glVertex3d(nodes[n3][0] - ref.x, nodes[n3][1] - ref.y,
+ nodes[n3][2] - ref.z);
} else if ( line[0] == 'q' ) {
/* continue a triangle strip */
n1 = n2 = 0;
- printf("continued tri strip = %s", line);
+ printf("continued tri strip = %s ", line);
sscanf(line, "q %d %d\n", &n1, &n2);
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;
+ glNormal3d(normals[n1][0], normals[n1][1], normals[n1][2]);
+ glVertex3d(nodes[n1][0] - ref.x, nodes[n1][1] - ref.y,
+ nodes[n1][2] - ref.z);
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;
+ printf(" (cont)\n");
+ glNormal3d(normals[n2][0], normals[n2][1], normals[n2][2]);
+ glVertex3d(nodes[n2][0] - ref.x, nodes[n2][1] - ref.y,
+ nodes[n2][2] - ref.z);
}
} else {
printf("Unknown line in %s = %s\n", path, line);
/* $Log$
-/* Revision 1.3 1997/10/31 04:49:12 curt
-/* Tweaking vertex orders.
+/* Revision 1.4 1997/11/14 00:26:49 curt
+/* Transform scenery coordinates earlier in pipeline when scenery is being
+/* created, not when it is being loaded. Precalculate normals for each node
+/* as average of the normals of each containing polygon so Garoude shading is
+/* now supportable.
/*
+ * 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.
*