needhelpppp

01-07-2003, 10:53 AM

i am attempting to make a triangle using bresenham line drawing algorithm, so far I have the cord for a line but it comes up with errors:

error C2449: found '{' at file scope (missing function header?)

error C2059: syntax error : '}'

Error executing cl.exe.

Casn anyone help me at least getting the line working and if possible tell me how i will then go on to complete the triangle. here is my code so far... i need to have it done by tonight if possible so im desperate it just refuses to work:

#include <stdlib.h>

#include <math.h>

#include <GL/glut.h>

int dx,dy;

int main();

{

public void lineBresenham(int x0, int y0, int x1, int y1, Color color) {

int pix = color.getRGB();

int dy = y1 - y0;

int dx = x1 - x0;

int stepx, stepy;

if (dy < 0) { dy = -dy; stepy = -1;

} else { stepy = 1;

}

if (dx < 0) { dx = -dx; stepx = -1;

} else { stepx = 1;

}

dy <<= 1; // dy is now 2*dy

dx <<= 1; // dx is now 2*dx

raster.setPixel(pix, x0, y0);

if (dx > dy) {

int fraction = dy - (dx >> 1); // same as 2*dy - dx

while (x0 != x1) {

if (fraction >= 0) {

y0 += stepy;

fraction -= dx; // same as fraction -= 2*dx

}

x0 += stepx;

fraction += dy; // same as fraction -= 2*dy

raster.setPixel(pix, x0, y0);

}

} else {

int fraction = dx - (dy >> 1);

while (y0 != y1) {

if (fraction >= 0) {

x0 += stepx;

fraction -= dy;

}

y0 += stepy;

fraction += dx;

raster.setPixel(pix, x0, y0);

}

}

}

}

error C2449: found '{' at file scope (missing function header?)

error C2059: syntax error : '}'

Error executing cl.exe.

Casn anyone help me at least getting the line working and if possible tell me how i will then go on to complete the triangle. here is my code so far... i need to have it done by tonight if possible so im desperate it just refuses to work:

#include <stdlib.h>

#include <math.h>

#include <GL/glut.h>

int dx,dy;

int main();

{

public void lineBresenham(int x0, int y0, int x1, int y1, Color color) {

int pix = color.getRGB();

int dy = y1 - y0;

int dx = x1 - x0;

int stepx, stepy;

if (dy < 0) { dy = -dy; stepy = -1;

} else { stepy = 1;

}

if (dx < 0) { dx = -dx; stepx = -1;

} else { stepx = 1;

}

dy <<= 1; // dy is now 2*dy

dx <<= 1; // dx is now 2*dx

raster.setPixel(pix, x0, y0);

if (dx > dy) {

int fraction = dy - (dx >> 1); // same as 2*dy - dx

while (x0 != x1) {

if (fraction >= 0) {

y0 += stepy;

fraction -= dx; // same as fraction -= 2*dx

}

x0 += stepx;

fraction += dy; // same as fraction -= 2*dy

raster.setPixel(pix, x0, y0);

}

} else {

int fraction = dx - (dy >> 1);

while (y0 != y1) {

if (fraction >= 0) {

x0 += stepx;

fraction -= dy;

}

y0 += stepy;

fraction += dx;

raster.setPixel(pix, x0, y0);

}

}

}

}