0
J'essaie d'implémenter une fonction zoom in/out dans mon code mandelbrot .. J'ai partiellement implémenté la fonction zoom mais quand on l'agrandit, il devient flou et ne voit plus le mandelbrot.Mandelbrot avec mise en œuvre du zoom en C
Voici mon code ...
// menu constants
#define MANDELBROT 0 // set
#define JULIA 1
#define ITERATIONS 2 // method
#define MAGNITUDE 3
#define REAL 4
#define IMAGINARY 5
#define RED 6 // color
#define YELLOW 7
#define GREEN 8
#define CYAN 9
#define BLUE 10
#define MAGENTA 11
#define WHITE 12
#define QUIT 13
#define ZOOM 14 // zoom
#define ZOOM_IN 15 // zoom in
#define ZOOM_OUT 16 // zoom out
#define KEY_ESC 27 /* ascii value for the escape key */
int set = MANDELBROT;
int nx, ny, imax=60, method=ITERATIONS, color=RED, hue=0, zoom = 1;
double x0=-0.5, y0a=0, dpi, power=2, xc=0.5, yc=0.05;
int ok=0;
double x1=-2.5, x2=1.5, y1f=-2, y2=2, zx, zy, ***screen;
double abs2(double x) {return (x>0)?x:(-x);}
double min(double x1, double x2) {return (x1<x2)?x1:x2;}
double max(double x1, double x2) {return (x1>x2)?x1:x2;}
double rem(double x1, double x2) {return x1-x2*(int)(x1/x2);}
void pixel(int x, int y, int r, int g, int b) {
glColor3f(r/256.0, g/256.0, b/256.0);
glVertex2i(x, y);
}
GLdouble xmin = -1.5, xmax = +1; /* edges of world "window" */
GLdouble ymin = -1.25, ymax = +1.25;
GLint viewportWidth, viewportHeight; /* size of "viewport" */
void reshape(int w, int h) {
glViewport(0,0, w,h);
viewportWidth = w;
viewportHeight = h;
}
#define NUM_COLORS 1000
static GLfloat colorMap[NUM_COLORS+1][3];
void initColorMap(void) {
GLfloat gray, dgray = 1.0/NUM_COLORS;
int i;
for (i = 0, gray = 1.0; i < NUM_COLORS; i++, gray -= dgray) {
colorMap[i][0] = gray;
colorMap[i][1] = gray*gray;
colorMap[i][2] = gray*gray*gray;
}
}
int escapeDistance(GLdouble x, GLdouble y, int maxDist) {
int iters = 0;
GLdouble a = x, b = y;
while (a*a + b*b < 2*2 && iters < maxDist) {
GLdouble a_old = a;
a = a*a - b*b + x;
b = 2*a_old*b + y;
iters++;
}
return iters;;
}
#define DETAILED_QUAD_SIZE 1
#define FAST_QUAD_SIZE 10
#define DETAILED_ITERS 1000
#define FAST_ITERS 1000
void mandelbrot(int quadSize, int maxIters) {
int W = viewportWidth/quadSize;
int H = viewportHeight/quadSize;
GLdouble dx = (xmax - xmin)/(W-1);
GLdouble dy = (ymax - ymin)/(H-1);
GLdouble x,y;
int r, c;
for (r = 0, y = ymax; r < H; r++, y -= dy) {
glBegin(GL_QUAD_STRIP);
for (c = 0, x = xmin; c < W; c++, x += dx) {
int dist = escapeDistance(x,y, maxIters);
glColor3fv(colorMap[dist*NUM_COLORS/maxIters]);
glVertex2d(x,y);
dist = escapeDistance(x,y-dy, maxIters);
glColor3fv(colorMap[dist*NUM_COLORS/maxIters]);
glVertex2d(x,y-dy);
}
glEnd();
}
}
GLboolean fastDraw = GL_FALSE;
void display(void) {
int unbounded = 0;
int r=0, g=0, b=0, i, n=(int)power/2-((rem(power,2)!=0)?1:0);
double x=0, y=0, xc1=xc, yc1=yc, dx=1/(dpi), x1=x0-0.5*nx/(dpi), x2=x0+0.5*nx/dpi, y1a=y0a-ny*dx/2, y2=y0a+ny*dx/2;
double t1=max(abs2(x1),abs2(x2)), t2=max(abs2(y1a),abs2(y2)), zm=sqrt(t1*t1+t2*t2);
int iy,ix,j; // supposed to go in for loop
double r1, g1, b1;
//char txt[100];
switch(color) { // calculations
case RED: hue=0 ; break;
case YELLOW: hue=60 ; break;
case GREEN: hue=120; break;
case CYAN: hue=180; break;
case BLUE: hue=240; break;
case MAGENTA: hue=300; break;
}
r1=max(0,min(1,abs2(rem(6-hue/60.0,6)-3)-1));
g1=max(0,min(1,abs2(rem(8-hue/60.0,6)-3)-1));
b1=max(0,min(1,abs2(rem(10-hue/60.0,6)-3)-1));
glClear(GL_COLOR_BUFFER_BIT);
glBegin(GL_POINTS);
for (iy=0; iy<=ny; ++iy) {
if (set==MANDELBROT) yc1=y2-iy*dx;
for (ix=0; ix<=nx; ++ix) {
if (set==JULIA) {x=x1+ix*dx; y=y2-iy*dx;} else {xc1=x1+ix*dx; x=0; y=0;}
unbounded=0;
for (i=0; (i<imax)&&(!unbounded); ++i) {
if (power>=2 && power<=25 && rem(power,1)==0) {
for (j=0; j<n; ++j) {t1=x*x-y*y; y=2*x*y; x=t1;}; // z^2
if (rem(power,2)!=0) {t1=x*(x*x-3*y*y); y=y*(3*x*x-y*y); x=t1;} // z^3
}
else {t1= atan2(y,x); t2= pow(x*x+y*y,power/2.0); x=t2* cos(power*t1); y=t2* sin(power*t1);} // z^n
x+=xc1; y+=yc1;
if (x*x+y*y>=4.0) unbounded=1;
}
if (unbounded) {
if (method==ITERATIONS) t1=1.0*i/imax;
else if (method==MAGNITUDE) t1= min(1, sqrt(x*x+y*y)/zm);
else t1= min(1, abs2((method==REAL)?x:y)/zm);
if (color==WHITE) {r=255*t1; g=r; b=r;}
else { // Note: brightness=(int)t1*100;
r = 255*((t1>0.5)?t1*r1+(1-t1*r1)*(2*t1-1):2*t1*r1);
g = 255*((t1>0.5)?t1*g1+(1-t1*g1)*(2*t1-1):2*t1*g1);
b = 255*((t1>0.5)?t1*b1+(1-t1*b1)*(2*t1-1):2*t1*b1);
}
pixel(ix,iy,r,g,b);
}
}
}
glEnd();
glColor3f(1,1,1);
//sprintf(txt, "%s Set: %f", (set == JULIA) ? "Julia" : "Mandelbrot", t1);
//text(10, 10, txt);
glutSwapBuffers();
}
GLboolean dragMouse = GL_FALSE; /* currently dragging mouse? */
GLboolean zoomMouse = GL_FALSE; /* currently zoom mouse? */
int mousex, mousey; /* last mouse position during drag */
void mouse(int button, int state, int x, int y) {
if (state == GLUT_DOWN) {
if (button == GLUT_LEFT_BUTTON) {
dragMouse = fastDraw = GL_TRUE;
glutSetCursor(GLUT_CURSOR_CROSSHAIR);
mousex = x;
mousey = y;
} else if (button == GLUT_RIGHT_BUTTON) {
zoomMouse = fastDraw = GL_TRUE;
glutSetCursor(GLUT_CURSOR_UP_DOWN);
mousey = y;
}
} else if (state == GLUT_UP && (dragMouse || zoomMouse)) {
dragMouse = zoomMouse = fastDraw = GL_FALSE;
glutPostRedisplay(); /* request a redisplay */
}
}
#define UNITS_PER_PIXEL 0.01 /* translation per pixel at zoom scale = 1.0 */
GLdouble unitsPerPixel = UNITS_PER_PIXEL;
GLdouble zoomsPerPixel = 1.0/100; /* scale = exp(z*zoomsPerPixel) */
void mouseMotion(int x, int y) {
if (dragMouse) {
GLdouble dx = (x - mousex)*unitsPerPixel;
GLdouble dy = (y - mousey)*unitsPerPixel;
xmin -= dx;
xmax -= dx;
ymin += dy;
ymax += dy;
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(xmin, xmax, ymin, ymax, -1,+1);
mousex = x;
mousey = y;
glutPostRedisplay(); /* request a redisplay */
} else if (zoomMouse) {
GLdouble scale = exp((y - mousey)*zoomsPerPixel);
GLdouble cx = 0.5*(xmin + xmax);
GLdouble cy = 0.5*(ymin + ymax);
xmin = (xmin - cx)*scale + cx;
xmax = (xmax - cx)*scale + cx;
ymin = (ymin - cy)*scale + cy;
ymax = (ymax - cy)*scale + cy;
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(xmin, xmax, ymin, ymax, -1,+1);
mousey = y;
unitsPerPixel *= scale;
glutPostRedisplay(); /* request a redisplay */
}
}
#define ESC 27
void keyboard(unsigned char key, int x, int y) {
if (key == ESC) exit(0);
}
int main(int argc, char *argv[]) {
nx=1200; ny=nx*3/4;
dpi=(nx/3);
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
glutInitWindowSize(nx, ny);
glutInitWindowPosition(550, 150);
glutCreateWindow("Mandelbrot");
gluOrtho2D(0, nx, 0, ny);
glutKeyboardFunc(keyboard);
glutMouseFunc(mouse);
glutMotionFunc(mouseMotion);
glutDisplayFunc(display);
glMatrixMode(GL_MODELVIEW);
glMatrixMode(GL_PROJECTION);
glClearColor(0, 0, 0, 1);
glutMainLoop();
return 0;
}
PS: Ce n'est pas devoir ..