nuclear@5: #include "opengl.h"
nuclear@3: #include "teapot.h"
nuclear@3: #include "teapot_data.h"
nuclear@3: 
nuclear@3: static void draw_patch(struct vec3 *bez_cp, int *index, int flip, int useg, int vseg, float scale);
nuclear@3: 
nuclear@3: int patch_subdivision = 6;
nuclear@3: 
nuclear@5: static int dlist_sub[32];
nuclear@5: 
nuclear@3: void bezier_teapot(float scale)
nuclear@3: {
nuclear@3: 	int i;
nuclear@3: 
nuclear@5: 	glMatrixMode(GL_MODELVIEW);
nuclear@5: 
nuclear@5: 	if(!dlist_sub[patch_subdivision]) {
nuclear@5: 		dlist_sub[patch_subdivision] = glGenLists(1);
nuclear@5: 		glNewList(dlist_sub[patch_subdivision], GL_COMPILE);
nuclear@5: 
nuclear@5: 		for(i=0; i<NUM_TEAPOT_PATCHES; i++) {
nuclear@5: 			float flip = teapot_part_flip[i];
nuclear@5: 			float rot = teapot_part_rot[i];
nuclear@5: 
nuclear@5: 			glPushMatrix();
nuclear@5: 			glTranslatef(0, -3.15 * 0.5, 0);
nuclear@5: 			glRotatef(rot, 0, 1, 0);
nuclear@5: 			glScalef(1, 1, flip);
nuclear@5: 			glRotatef(-90, 1, 0, 0);
nuclear@5: 
nuclear@5: 			draw_patch(teapot_verts, teapot_index + i * 16, flip < 0.0 ? 1 : 0, patch_subdivision, patch_subdivision, 1.0);
nuclear@5: 
nuclear@5: 			glPopMatrix();
nuclear@5: 		}
nuclear@5: 
nuclear@5: 		glEndList();
nuclear@5: 	}
nuclear@5: 
nuclear@3: 	scale /= 2.0;
nuclear@5: 	glPushMatrix();
nuclear@5: 	glScalef(scale, scale, scale);
nuclear@5: 	glCallList(dlist_sub[patch_subdivision]);
nuclear@5: 	glPopMatrix();
nuclear@3: }
nuclear@3: 
nuclear@3: static void draw_patch(struct vec3 *bez_cp, int *index, int flip, int useg, int vseg, float scale)
nuclear@3: {
nuclear@3: 	static const float uoffs[2][4] = {{0, 0, 1, 1}, {1, 1, 0, 0}};
nuclear@3: 	static const float voffs[4] = {0, 1, 1, 0};
nuclear@3: 
nuclear@3: 	int i, j, k;
nuclear@3: 	struct vec3 cp[16];
nuclear@3: 	struct vec3 pt, n;
nuclear@3: 	float u, v;
nuclear@3: 	float du = 1.0 / useg;
nuclear@3: 	float dv = 1.0 / vseg;
nuclear@3: 
nuclear@3: 	/* collect control points */
nuclear@3: 	for(i=0; i<16; i++) {
nuclear@3: 		cp[i] = bez_cp[index[i]];
nuclear@3: 	}
nuclear@3: 
nuclear@3: 	glBegin(GL_QUADS);
nuclear@3: 	glColor3f(1, 1, 1);
nuclear@3: 
nuclear@3: 	u = 0;
nuclear@3: 	for(i=0; i<useg; i++) {
nuclear@3: 		v = 0;
nuclear@3: 		for(j=0; j<vseg; j++) {
nuclear@3: 
nuclear@3: 			for(k=0; k<4; k++) {
nuclear@3: 				pt = bezier_patch(cp, u + uoffs[flip][k] * du, v + voffs[k] * dv);
nuclear@3: 
nuclear@3: 				/* top/bottom normal hack */
nuclear@3: 				if(pt.z > 3.14) {
nuclear@3: 					n.x = n.y = 0.0f;
nuclear@3: 					n.z = 1.0f;
nuclear@3: 				} else if(pt.z < 0.00001) {
nuclear@3: 					n.x = n.y = 0.0f;
nuclear@3: 					n.z = -1.0f;
nuclear@3: 				} else {
nuclear@3: 					n = bezier_patch_norm(cp, u + uoffs[flip][k] * du, v + voffs[k] * dv);
nuclear@3: 				}
nuclear@3: 
nuclear@3: 				glTexCoord2f(u, v);
nuclear@3: 				glNormal3f(n.x, n.y, n.z);
nuclear@3: 				glVertex3f(pt.x * scale, pt.y * scale, pt.z * scale);
nuclear@3: 			}
nuclear@3: 
nuclear@3: 			v += dv;
nuclear@3: 		}
nuclear@3: 		u += du;
nuclear@3: 	}
nuclear@3: 
nuclear@3: 	glEnd();
nuclear@3: }