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OpenGL interpolate and skinning

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anerol    122
I'm an Italian Student and I have to do a function in openGL that calculate a interpolated surface between a grid of point of an immagine in .ppm. How Can I do this?? It's similar to skinning...but I dont know... Interpolated points are in input Through a ppm file, and I've to do a curves that interpolate this points! For skinning I have this: int skinning(struct snurbs* surf, GLfloat** CPcurve, int n, GLfloat* U, int nu, int ncpc, GLfloat* dist, int orderv, int dim) { int orderu = nu - ncpc; GLfloat* CP,*v_n,*V,*P,*Q,*CQ; int i,j,k; int nv; if (orderv>n) return 0; if ((dim != 3) && (dim != 4)) return 0; nv = n + orderv; CP = malloc(dim*ncpc*n*sizeof(GLfloat)); CQ = malloc(dim*ncpc*n*sizeof(GLfloat)); v_n = malloc(n*sizeof(GLfloat)); V = malloc(nv*sizeof(GLfloat)); P = malloc(dim*n*sizeof(GLfloat)); Q = malloc(dim*n*sizeof(GLfloat)); // inizializzazione della matrice dei punti di controllo delle curve sezione if (dim == 3) for (i=0;i<n;i++) for (j=0;j<ncpc;j++) { CP[dim*(ncpc*i+j)]=CPcurve[i][3*j]; CP[dim*(ncpc*i+j)+1]=CPcurve[i][3*j+1]; CP[dim*(ncpc*i+j)+2]=dist[i]; } else for (i=0;i<n;i++) for (j=0;j<ncpc;j++) { CP[dim*(ncpc*i+j)]=CPcurve[i][4*j]; CP[dim*(ncpc*i+j)+1]=CPcurve[i][4*j+1]; CP[dim*(ncpc*i+j)+2]=dist[i]; CP[dim*(ncpc*i+j)+3]=CPcurve[i][4*j+3]; } // calcolo del vettore nodale V del vettore v_n dei valori del parametro per cui si ha interpolazione find_node_V(CP,n,ncpc,orderv,dim,v_n,V); for (i=0;i<ncpc;i++) { for (j=0;j<n;j++) for (k=0;k<dim;k++) P[dim*j+k]=CP[dim*(ncpc*j+i)+k]; // calcolo dei punti di controllo della superficie interpolante curve_interp(P,v_n,n,dim,V,nv,Q); for (j=0;j<n;j++) for (k=0;k<dim;k++) CQ[dim*(ncpc*j+i)+k]=Q[dim*j+k]; } free(CP); free(v_n); free(P); free(Q); surf->CP = CQ; surf->dim = dim; surf->ncpu = ncpc; surf->ncpv = n; surf->nu = nu; surf->nv = nv; surf->orderu = orderu; surf->orderv = orderv; surf->U = malloc(nu*sizeof(GLfloat)); for (i=0;i<nu;i++) surf->U[i] = U[i]; surf->V = V; return 1; } My new function is: int gridInterp(GLuint *image,?????) { int n; int m; FILE *fd; int k, nm; char c; int i; char b[100]; float s; int red, green, blue; printf("enter file name\n"); scanf("%s", b); fd = fopen(b, "r"); fscanf(fd,"%[^\n] ",b); if(b[0]!='P'|| b[1] != '3') { printf("%s is not a PPM file!\n", b); exit(0); } printf("%s is a PPM file\n",b); fscanf(fd, "%c",&c); while(c == '#') { fscanf(fd, "%[^\n] ", b); printf("%s\n",b); fscanf(fd, "%c",&c); } ungetc(c,fd); //reinserisce c nello strem fscanf(fd, "%d %d %d", &n, &m, &k);//larghezza altezza massimo valore di colore printf("%d rows %d columns max value= %d\n",n,m,k); nm = n*m; image=malloc(3*sizeof(GLuint)*nm); s=255./k; //terne di RGB (una per ogni pixel) for(i=0;i<nm;i++) { fscanf(fd,"%d %d %d",&red, &green, &blue ); image[3*nm-3*i-3]=red; image[3*nm-3*i-2]=green; image[3*nm-3*i-1]=blue; } //in image ho i punti da interpolare and now???? How can i do??? } Thanks Carmen

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