GLUT Shapes Demo

/*

* GLUT Shapes Demo

*

* Written by Nigel Stewart November 2003

*

* This program is test harness for the sphere, cone

* and torus shapes in GLUT.

*

* Spinning wireframe and smooth shaded shapes are

* displayed until the ESC or q key is pressed. The

* number of geometry stacks and slices can be adjusted

* using the + and - keys.

*/

#ifdef __APPLE__

#include <GLUT/glut.h>

#else

#include <GL/glut.h>

#endif

#define pantx 0.015625f

#define panty 0.020834f

#include <Math.h>

#include <stdlib.h>

#include <iostream>

#include <string>

using namespace std;

int ind=-1;

static int slices = 16;

static int stacks = 16;

int w=640, h=480;

int ncontrol=0;

int npts=0;

char* men="Punto: Activo. Puedes arrastrar los puntos";

float controles[100][3];/*={

{ -4.0, -4.0, 0.0},

{ -2.0, 4.0, 0.0},

{2.0, -4.0, 0.0}, {4.0, 4.0, 0.0}, {-4.0, 4.0, 0.0}};

*/

float mat[4][4] = { {-1,3,-3,1},

{ 3,-6,3,0},

{ -3,0,3,0},

{ 1,4,1,0}

};

float x=0, y=0;

bool act=true, mos=false;

float CalcularPuntos(float u){

float sum;

float sx=0, sy=0;

for(int j=0; j<npts-3;j++){

for(int i=0; i<4;i++){

sum=mat[0][i]*pow(u,3)+mat[1][i]*pow(u,2)+mat[2][i]*u+mat[3][i];

sx+=sum*controles[i+j][0];

sy+=sum*controles[i+j][1];

}

x=sx/6;

y=sy/6;}

}

void BSpline(){

glBegin(GL_LINE_STRIP);

float u;

for(u=0; u<=1;u+=0.01){

CalcularPuntos(u);

glVertex2f(x,y);

}

glEnd();

}

void dibujarControles(){

glPointSize(4.0);

glBegin(GL_POINTS);

for(int i=0; i<ncontrol;i++)

glVertex2f(controles[i][0],controles[i][1]);

glEnd();

glPointSize(1.0);

}

static void resize(int width, int height)

{

const float ar = (float) width / (float) height;

glViewport(0, 0, width, height);

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

glOrtho(-5.0,5.0,-5.0,5.0,-10.0,10.0);

glMatrixMode(GL_MODELVIEW);

glLoadIdentity() ;

}

static void display(void)

{

...