glm.zip_3D modelling OpenGL_OpenGL glm_glm_glm open_opengl

/* glm.c Nate Robins, 1997, 2000 nate@pobox.com, http://www.pobox.com/~nate Wavefront OBJ model file format reader/writer/manipulator. Includes routines for generating smooth normals with preservation of edges, welding redundant vertices & texture coordinate generation (spheremap and planar projections) + more. Improved version of GLM - 08.05.2008 Tudor Carean Added support for textures and loading callbacks */ #include <stdafx.h> #include <math.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <assert.h> #include "glm.h" //#define DebugVisibleSurfaces #define total_textures 5 #define T(x) (model->triangles[(x)]) GLuint glmLoadTexture(char *filename, GLboolean alpha, GLboolean repeat, GLboolean filtering, GLboolean mipmaps, GLfloat *texcoordwidth, GLfloat *texcoordheight); /* _GLMnode: general purpose node */ typedef struct _GLMnode { GLuint index; GLboolean averaged; struct _GLMnode* next; } GLMnode; /* glmMax: returns the maximum of two floats */ static GLfloat glmMax(GLfloat a, GLfloat b) { if (b > a) return b; return a; } /* glmAbs: returns the absolute value of a float */ static GLfloat glmAbs(GLfloat f) { if (f < 0) return -f; return f; } /* glmDot: compute the dot product of two vectors * * u - array of 3 GLfloats (GLfloat u[3]) * v - array of 3 GLfloats (GLfloat v[3]) */ GLfloat glmDot(GLfloat* u, GLfloat* v) { assert(u); assert(v); return u[0]*v[0] + u[1]*v[1] + u[2]*v[2]; } /* glmCross: compute the cross product of two vectors * * u - array of 3 GLfloats (GLfloat u[3]) * v - array of 3 GLfloats (GLfloat v[3]) * n - array of 3 GLfloats (GLfloat n[3]) to return the cross product in */ static GLvoid glmCross(GLfloat* u, GLfloat* v, GLfloat* n) { assert(u); assert(v); assert(n); n[0] = u[1]*v[2] - u[2]*v[1]; n[1] = u[2]*v[0] - u[0]*v[2]; n[2] = u[0]*v[1] - u[1]*v[0]; } /* glmNormalize: normalize a vector * * v - array of 3 GLfloats (GLfloat v[3]) to be normalized */ static GLvoid glmNormalize(GLfloat* v) { GLfloat l; assert(v); l = (GLfloat)sqrt(v[0]*v[0] + v[1]*v[1] + v[2]*v[2]); v[0] /= l; v[1] /= l; v[2] /= l; } /* glmEqual: compares two vectors and returns GL_TRUE if they are * equal (within a certain threshold) or GL_FALSE if not. An epsilon * that works fairly well is 0.000001. * * u - array of 3 GLfloats (GLfloat u[3]) * v - array of 3 GLfloats (GLfloat v[3]) */ static GLboolean glmEqual(GLfloat* u, GLfloat* v, GLfloat epsilon) { if (glmAbs(u[0] - v[0]) < epsilon && glmAbs(u[1] - v[1]) < epsilon && glmAbs(u[2] - v[2]) < epsilon) { return GL_TRUE; } return GL_FALSE; } /* glmWeldVectors: eliminate (weld) vectors that are within an * epsilon of each other. * * vectors - array of GLfloat[3]'s to be welded * numvectors - number of GLfloat[3]'s in vectors * epsilon - maximum difference between vectors * */ GLfloat* glmWeldVectors(GLfloat* vectors, GLuint* numvectors, GLfloat epsilon) { GLfloat* copies; GLuint copied; GLuint i, j; copies = (GLfloat*)malloc(sizeof(GLfloat) * 3 * (*numvectors + 1)); memcpy(copies, vectors, (sizeof(GLfloat) * 3 * (*numvectors + 1))); copied = 1; for (i = 1; i <= *numvectors; i++) { for (j = 1; j <= copied; j++) { if (glmEqual(&vectors[3 * i], &copies[3 * j], epsilon)) { goto duplicate; } } /* must not be any duplicates -- add to the copies array */ copies[3 * copied + 0] = vectors[3 * i + 0]; copies[3 * copied + 1] = vectors[3 * i + 1]; copies[3 * copied + 2] = vectors[3 * i + 2]; j = copied; /* pass this along for below */ copied++; duplicate: /* set the first component of this vector to point at the correct index into the new copies array */ vectors[3 * i + 0] = (GLfloat)j; } *numvectors = copied-1; return copies; } /* glmFindGroup: Find a group in the model */ GLMgroup* glmFindGroup(GLMmodel* model, char* name) { GLMgroup* group; assert(model); group = model->groups; while(group) { if (!strcmp(name, group->name)) break; group = group->next; } return group; } /* glmAddGroup: Add a group to the model */ GLMgroup* glmAddGroup(GLMmodel* model, char* name) { GLMgroup* group; group = glmFindGroup(model, name); if (!group) { group = (GLMgroup*)malloc(sizeof(GLMgroup)); group->name = strdup(name); group->material = 0; group->numtriangles = 0; group->triangles = NULL; group->next = model->groups; model->groups = group; model->numgroups++; } return group; } /* glmFindGroup: Find a material in the model */ GLuint glmFindMaterial(GLMmodel* model, char* name) { GLuint i; /* XXX doing a linear search on a string key'd list is pretty lame, but it works and is fast enough for now. */ for (i = 0; i < model->nummaterials; i++) { if (!strcmp(model->materials[i].name, name)) goto found; } /* didn't find the name, so print a warning and return the default material (0). */ printf("glmFindMaterial(): can't find material \"%s\".\n", name); i = 0; found: return i; } /* glmDirName: return the directory given a path * * path - filesystem path * * NOTE: the return value should be free'd. */ static char* glmDirName(char* path) { char* dir; char* s; dir = strdup(path); s = strrchr(dir, '/'); if (s) s[1] = '\0'; else dir[0] = '\0'; return dir; } int glmFindOrAddTexture(GLMmodel* model, char* name,mycallback *call) { GLuint i; char *dir, *filename; float width, height; char *numefis = name; while (*numefis==' ') numefis++; for (i = 0; i < model->numtextures; i++) { if (!strcmp(model->textures[i].name, numefis)) return i; } char afis[80]; sprintf(afis,"Loading Textures (%s )...",name); int procent = ((float)((float)model->numtextures*30/total_textures)/100)*(call->end-call->start)+call->start; if (call) call->loadcallback(procent,afis); // textures represent 30% from the model (just saying :)) if (strstr(name,":\\")) { filename = (char*)malloc(sizeof(char) * (strlen(name) + 1)); strcpy(filename,name); } else { dir = glmDirName(model->pathname); filename = (char*)malloc(sizeof(char) * (strlen(dir) + strlen(numefis) + 1)); strcpy(filename, dir); //strcpy(filename, numefis); strcat(filename, numefis); free(dir); } int lung = strlen(filename); if (filename[lung-1]<32) filename[lung-1]=0; if (filename[lung-2]<32) filename[lung-2]=0; model->numtextures++; model->textures = (GLMtexture*)realloc(model->textures, sizeof(GLMtexture)*model->numtextures); model->textures[model->numtextures-1].name = strdup(numefis); model->textures[model->numtextures-1].id = glmLoadTexture(filename, GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE, &width, &height); model->textures[model->numtextures-1].width = width; model->textures[model->numtextures-1].height = height; free(filename); return model->numtextures-1; } /* glmReadMTL: read a wavefront material library file * * model - properly initialized GLMmodel structure * name - name of the material library */ static GLvoid glmReadMTL(GLMmodel* model, char* name, mycallback *call) { FILE* file;