comment gerer la vitesse dans la courbe de bezier en c++

Question

salut, en faite je suis un peu bloqué ayant programmé ma courbe de bezier je voulais ajouter la vitesse mais je sais comment on fait tout ce je sais c 


typedef struct point_3d {	// Structure for a 3 dimensional point (NEW)
double x, y, z;
} point_3d;

typedef struct bpatch {		// Structure for a 3rd degree bezier patch (NEW)
point_3danchors[4][4];	// 4x4 grid of anchor points
GLuint dlBPatch;	// Display List for Bezier Patch
GLuint texture;		// Texture for the patch
} 
BEZIER_PATCH;

HDC hDC=NULL;		// Private GDI Device Context
HGLRC hRC=NULL;	       // Permanent Rendering Context
HWND hWnd=NULL;	      // Holds Our Window Handle
HINSTANCE hInstance;	// Holds The Instance Of The Application

DEVMODE	DMsaved;  // Saves the previous screen settings (NEW)
//bool	
keys[256];     // Array Used For The Keyboard Routine
//bool			
active=TRUE;   // Window Active Flag Set To TRUE By Default
//bool			
fullscreen=TRUE; // Fullscreen Flag Set To Fullscreen Mode By Default

GLfloat	rotz = 0.0f;		// Rotation about the Z axis
BEZIER_PATCH	mybezier;	// The bezier patch we're going to use (NEW)
BOOL	showCPoints=TRUE;// Toggles displaying the control point grid (NEW)
int divs = 7;	// Number of intrapolations (conrols poly resolution) (NEW)


LRESULT	CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);	// Declaration For WndProc


glEnd();  // End the haptic shape.
hlEndShape();
//End the haptic frame.
    hlEndFrame();

    
   
}


// Adds 2 points. Don't just use '+' ;)
 point_3d pointAdd(double
 point_3d p, point_3d q) {
p.x += q.x;		p.y += q.y;		p.z += q.z;
return p;
}

// Multiplies a point and a constant. Don't just use '*'
double point_3d pointTimes(double c, point_3d p) {
p.x *= c;	p.y *= c;	p.z *= c;
return p;
}

// Function for quick point creation
double point_3d makePoint(double a, double b, double c) {
point_3d p;
p.x a;	p.y b;	p.z = c;
return p;
}


// Calculates 3rd degree polynomial based on array of 4 points
// and a single variable (u) which is generally between 0 and 1
point_3d Bernstein(float u, point_3d *p) {
point_3d	a, b, c, d, r;

a = pointTimes(pow(u,3), p[0]);
b = pointTimes(3*pow(u,2)*(1-u), p[1]);
c = pointTimes(3*u*pow((1-u),2), p[2]);
d = pointTimes(pow((1-u),3), p[3]);

r = pointAdd(pointAdd(a, b), pointAdd(c, d));

return r;
}

luhtor · Answer

La vitesse de quoi ?

bekha · Answer

beman

bekha · Answer

c'est à dire  l'algo qui permet de gerer la vitesse a un point de la courbe. Je suis preneur pour toute idée ou toute implementation quasi-toute-faite...

Merci d'avance.
beman

luhtor · Answer

Je comprends pas ce que tu veux dire. Un point de la courbe n'a pas de vitesse, il a une tangente tout au plus.

Comment gerer la vitesse dans la courbe de bezier en c++

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