+/*
+ * Copyright (C) 1998 Janne Löf <jlof@mail.student.oulu.fi>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+
+
+#include "lw.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+
+#define wxInt32 int
+#define wxUint32 unsigned int
+
+#ifndef FALSE
+#define FALSE 0
+#endif
+
+#ifndef TRUE
+#define TRUE 1
+#endif
+
+#define MK_ID(a,b,c,d) ((((wxUint32)(a))<<24)| \
+ (((wxUint32)(b))<<16)| \
+ (((wxUint32)(c))<< 8)| \
+ (((wxUint32)(d)) ))
+
+#define ID_FORM MK_ID('F','O','R','M')
+#define ID_LWOB MK_ID('L','W','O','B')
+#define ID_PNTS MK_ID('P','N','T','S')
+#define ID_SRFS MK_ID('S','R','F','S')
+#define ID_SURF MK_ID('S','U','R','F')
+#define ID_POLS MK_ID('P','O','L','S')
+#define ID_COLR MK_ID('C','O','L','R')
+
+static wxInt32 read_char(FILE *f)
+{
+ int c = fgetc(f);
+ return c;
+}
+
+static wxInt32 read_short(FILE *f)
+{
+ return (read_char(f)<<8) | read_char(f);
+}
+
+static wxInt32 read_long(FILE *f)
+{
+ return (read_char(f)<<24) | (read_char(f)<<16) | (read_char(f)<<8) | read_char(f);
+}
+
+static GLfloat read_float(FILE *f)
+{
+ wxInt32 x = read_long(f);
+ return *(GLfloat*)&x;
+}
+
+static int read_string(FILE *f, char *s)
+{
+ int c;
+ int cnt = 0;
+ do {
+ c = read_char(f);
+ if (cnt < LW_MAX_NAME_LEN)
+ s[cnt] = c;
+ else
+ s[LW_MAX_NAME_LEN-1] = 0;
+ cnt++;
+ } while (c != 0);
+ /* if length of string (including \0) is odd skip another byte */
+ if (cnt%2) {
+ read_char(f);
+ cnt++;
+ }
+ return cnt;
+}
+
+static void read_srfs(FILE *f, int nbytes, lwObject *lwo)
+{
+ int guess_cnt = lwo->material_cnt;
+
+ while (nbytes > 0) {
+ lwMaterial *material;
+
+ /* allocate more memory for materials if needed */
+ if (guess_cnt <= lwo->material_cnt) {
+ guess_cnt += guess_cnt/2 + 4;
+ lwo->material = realloc(lwo->material, sizeof(lwMaterial)*guess_cnt);
+ }
+ material = lwo->material + lwo->material_cnt++;
+
+ /* read name */
+ nbytes -= read_string(f,material->name);
+
+ /* defaults */
+ material->r = 0.7;
+ material->g = 0.7;
+ material->b = 0.7;
+ }
+ lwo->material = realloc(lwo->material, sizeof(lwMaterial)*lwo->material_cnt);
+}
+
+
+static void read_surf(FILE *f, int nbytes, lwObject *lwo)
+{
+ int i;
+ char name[LW_MAX_NAME_LEN];
+ lwMaterial *material = NULL;
+
+ /* read surface name */
+ nbytes -= read_string(f,name);
+
+ /* find material */
+ for (i=0; i< lwo->material_cnt; i++) {
+ if (strcmp(lwo->material[i].name,name) == 0) {
+ material = &lwo->material[i];
+ break;
+ }
+ }
+
+ /* read values */
+ while (nbytes > 0) {
+ int id = read_long(f);
+ int len = read_short(f);
+ nbytes -= 6 + len + (len%2);
+
+ switch (id) {
+ case ID_COLR:
+ material->r = read_char(f) / 255.0;
+ material->g = read_char(f) / 255.0;
+ material->b = read_char(f) / 255.0;
+ read_char(f); /* dummy */
+ break;
+ default:
+ fseek(f, len+(len%2), SEEK_CUR);
+ }
+ }
+}
+
+
+static void read_pols(FILE *f, int nbytes, lwObject *lwo)
+{
+ int guess_cnt = lwo->face_cnt;
+
+ while (nbytes > 0) {
+ lwFace *face;
+ int i;
+
+ /* allocate more memory for polygons if necessary */
+ if (guess_cnt <= lwo->face_cnt) {
+ guess_cnt += guess_cnt + 4;
+ lwo->face = realloc(lwo->face, sizeof(lwFace)*guess_cnt);
+ }
+ face = lwo->face + lwo->face_cnt++;
+
+ /* number of points in this face */
+ face->index_cnt = read_short(f);
+ nbytes -= 2;
+
+ /* allocate space for points */
+ face->index = calloc(sizeof(int)*face->index_cnt,1);
+
+ /* read points in */
+ for (i=0; i<face->index_cnt; i++) {
+ face->index[i] = read_short(f);
+ nbytes -= 2;
+ }
+
+ /* read surface material */
+ face->material = read_short(f);
+ nbytes -= 2;
+
+ /* skip over detail polygons */
+ if (face->material < 0) {
+ int det_cnt;
+ face->material = -face->material;
+ det_cnt = read_short(f);
+ nbytes -= 2;
+ while (det_cnt-- > 0) {
+ int cnt = read_short(f);
+ fseek(f, cnt*2+2, SEEK_CUR);
+ nbytes -= cnt*2+2;
+ }
+ }
+ face->material -= 1;
+ }
+ /* readjust to true size */
+ lwo->face = realloc(lwo->face, sizeof(lwFace)*lwo->face_cnt);
+}
+
+
+
+static void read_pnts(FILE *f, int nbytes, lwObject *lwo)
+{
+ int i;
+ lwo->vertex_cnt = nbytes / 12;
+ lwo->vertex = calloc(sizeof(GLfloat)*lwo->vertex_cnt*3, 1);
+ for (i=0; i<lwo->vertex_cnt; i++) {
+ lwo->vertex[i*3+0] = read_float(f);
+ lwo->vertex[i*3+1] = read_float(f);
+ lwo->vertex[i*3+2] = read_float(f);
+ }
+}
+
+
+
+
+
+
+int lw_is_lwobject(const char *lw_file)
+{
+ FILE *f = fopen(lw_file, "rb");
+ if (f) {
+ wxInt32 form = read_long(f);
+ wxInt32 nlen = read_long(f);
+ wxInt32 lwob = read_long(f);
+ fclose(f);
+ if (form == ID_FORM && nlen != 0 && lwob == ID_LWOB)
+ return TRUE;
+ }
+ return FALSE;
+}
+
+
+lwObject *lw_object_read(const char *lw_file)
+{
+ FILE *f = NULL;
+ lwObject *lw_object = NULL;
+
+ wxInt32 form_bytes = 0;
+ wxInt32 read_bytes = 0;
+
+ /* open file */
+ f = fopen(lw_file, "rb");
+ if (f == NULL) {
+ return NULL;
+ }
+
+ /* check for headers */
+ if (read_long(f) != ID_FORM) {
+ fclose(f);
+ return NULL;
+ }
+ form_bytes = read_long(f);
+ read_bytes += 4;
+
+ if (read_long(f) != ID_LWOB) {
+ fclose(f);
+ return NULL;
+ }
+
+ /* create new lwObject */
+ lw_object = calloc(sizeof(lwObject),1);
+
+ /* read chunks */
+ while (read_bytes < form_bytes) {
+ wxInt32 id = read_long(f);
+ wxInt32 nbytes = read_long(f);
+ read_bytes += 8 + nbytes + (nbytes%2);
+
+ switch (id) {
+ case ID_PNTS:
+ read_pnts(f, nbytes, lw_object);
+ break;
+ case ID_POLS:
+ read_pols(f, nbytes, lw_object);
+ break;
+ case ID_SRFS:
+ read_srfs(f, nbytes, lw_object);
+ break;
+ case ID_SURF:
+ read_surf(f, nbytes, lw_object);
+ break;
+ default:
+ fseek(f, nbytes + (nbytes%2), SEEK_CUR);
+ }
+ }
+
+ fclose(f);
+ return lw_object;
+}
+
+
+
+void lw_object_free(lwObject *lw_object)
+{
+ if (lw_object->face) {
+ int i;
+ for (i=0; i<lw_object->face_cnt; i++)
+ free(lw_object->face[i].index);
+ free(lw_object->face);
+ }
+ free(lw_object->material);
+ free(lw_object->vertex);
+ free(lw_object);
+}
+
+
+
+
+
+#define PX(i) (lw_object->vertex[face->index[i]*3+0])
+#define PY(i) (lw_object->vertex[face->index[i]*3+1])
+#define PZ(i) (lw_object->vertex[face->index[i]*3+2])
+void lw_object_show(const lwObject *lw_object)
+{
+ int i,j;
+ int prev_index_cnt = -1;
+ int prev_material = -1;
+ GLfloat prev_nx = 0;
+ GLfloat prev_ny = 0;
+ GLfloat prev_nz = 0;
+
+ for (i=0; i<lw_object->face_cnt; i++) {
+ GLfloat ax,ay,az,bx,by,bz,nx,ny,nz,r;
+ const lwFace *face = lw_object->face+i;
+
+ /* ignore faces with less than 3 points */
+ if (face->index_cnt < 3)
+ continue;
+
+ /* calculate normal */
+ ax = PX(1) - PX(0);
+ ay = PY(1) - PY(0);
+ az = PZ(1) - PZ(0);
+
+ bx = PX(face->index_cnt-1) - PX(0);
+ by = PY(face->index_cnt-1) - PY(0);
+ bz = PZ(face->index_cnt-1) - PZ(0);
+
+ nx = ay * bz - az * by;
+ ny = az * bx - ax * bz;
+ nz = ax * by - ay * bx;
+
+ r = sqrt(nx*nx + ny*ny + nz*nz);
+ if (r < 0.000001) /* avoid division by zero */
+ continue;
+ nx /= r;
+ ny /= r;
+ nz /= r;
+
+ /* glBegin/glEnd */
+ if (prev_index_cnt != face->index_cnt || prev_index_cnt > 4) {
+ if (prev_index_cnt > 0) glEnd();
+ prev_index_cnt = face->index_cnt;
+ switch (face->index_cnt) {
+ case 3:
+ glBegin(GL_TRIANGLES);
+ break;
+ case 4:
+ glBegin(GL_QUADS);
+ break;
+ default:
+ glBegin(GL_POLYGON);
+ }
+ }
+
+ /* update material if necessary */
+ if (prev_material != face->material) {
+ prev_material = face->material;
+ glColor3f(lw_object->material[face->material].r,
+ lw_object->material[face->material].g,
+ lw_object->material[face->material].b);
+ }
+
+ /* update normal if necessary */
+ if (nx != prev_nx || ny != prev_ny || nz != prev_nz) {
+ prev_nx = nx;
+ prev_ny = ny;
+ prev_nz = nz;
+ glNormal3f(nx,ny,nz);
+ }
+
+ /* draw polygon/triangle/quad */
+ for (j=0; j<face->index_cnt; j++)
+ glVertex3f(PX(j),PY(j),PZ(j));
+
+ }
+
+ /* if glBegin was called call glEnd */
+ if (prev_index_cnt > 0)
+ glEnd();
+}
+
+
+GLfloat lw_object_radius(const lwObject *lwo)
+{
+ int i;
+ double max_radius = 0.0;
+
+ for (i=0; i<lwo->vertex_cnt; i++) {
+ GLfloat *v = &lwo->vertex[i*3];
+ double r = v[0]*v[0] + v[1]*v[1] + v[2]*v[2];
+ if (r > max_radius)
+ max_radius = r;
+ }
+ return sqrt(max_radius);
+}
+
+void lw_object_scale(lwObject *lwo, GLfloat scale)
+{
+ int i;
+
+ for (i=0; i<lwo->vertex_cnt; i++) {
+ lwo->vertex[i*3+0] *= scale;
+ lwo->vertex[i*3+1] *= scale;
+ lwo->vertex[i*3+2] *= scale;
+ }
+}
+
+
projects / wxWidgets.git / commitdiff
