### Drawing functions - (Rectangle & Ellipse)!

Posted:

**Sun Mar 17, 2013 8:05 pm**Hello everybody!

As I have been working with the world editor

for Sabre, I have had to create some drawing functions, and

since they turned out pretty well, I decided to share them with you.

There is 3 functions in the .ged and they are:

These functions are free to use for everyone.

I would of course like to have my name in the credits of your game if you use these,

but I can't force you to add it.

Download the example ged:

Or if you think you don't need the .ged, here's the code for the functions:

EDIT: Fixed the bug with the ellipse's edges, see the picture below for how the edges look like now.

The example and the code have been updated, too.

As I have been working with the world editor

for Sabre, I have had to create some drawing functions, and

since they turned out pretty well, I decided to share them with you.

There is 3 functions in the .ged and they are:

- setColor(); - this is used for setting the colors the functions use
- drawRectangle(); - this is for drawing rectangles and filled rectangles
- drawEllipse(); - this is for drawing ellipses and filled ellipses

These functions are free to use for everyone.

I would of course like to have my name in the credits of your game if you use these,

but I can't force you to add it.

Download the example ged:

Or if you think you don't need the .ged, here's the code for the functions:

- Code: Select all
`//Definitions which make it easier to use the functions.`

//With these definitions it is possible, for example, to write FILL_OFF instead of 0, when

//using a drawing function and not wanting it to fill the drawn shape. This makes it easier and

//clearer to use the functions.

#define FILL_OFF 0

#define FILL_ON 1

#define NO_FILL_COLOR 0, 0, 0, 0, 1

//This can be used to avoid writing multiple 0's when setting

//a color for a shape that won't have a fill in it.

float ALPHA, ALPHA2; //These are the alpha variables for the edge color and for the fill color.

int R, R2, G, G2, B, B2, SIZE, SIZE2; //These are the color and size variables for the edge color

//and for the fill color. (The 2-variables are the fill variables.)

//This is a function for setting the colours to be used.

void setColor(int r, int g, int b, float alpha, int size, int r2, int g2, int b2, float alpha2, int size2)

{

R = r; G = g; B = b; SIZE = size; ALPHA = alpha;

R2 = r2; G2 = g2; B2 = b2; SIZE2 = size2; ALPHA2 = alpha2;

}

//This is a function for drawing a rectangle / square.

void drawRectangle(int lineBeginX, int lineBeginY, int lineX, int lineY, int fill)

{

setpen(R, G, B, ALPHA, SIZE);

moveto(lineBeginX, lineBeginY);

lineto(lineX, lineBeginY);

lineto(lineX, lineY);

lineto(lineBeginX, lineY);

lineto(lineBeginX, lineBeginY);

if (fill == FILL_ON) //This is equal to 'if (fill == 1)' because of the #defines at the top.

{

int i;

setpen(R2, G2, B2, ALPHA2, SIZE2);

//For loop for filling the rectangle.

for (i = min(lineBeginX, lineX) + 1; i < max(lineBeginX, lineX); i ++)

{

moveto(i, min(lineBeginY, lineY) + 1);

lineto(i, max(lineBeginY, lineY) - 1);

}

}

}

//This is a function for drawing an ellipse / circle.

void drawEllipse(int lineBeginX, int lineBeginY, int lineX, int lineY, int fill)

{

float t; //This variable will be used for the for loop for drawing the ellipse.

int i, a, b, centerX, centerY;

//a is the horizontal diametre of the ellipse.

//b is the vertical diametre of the ellipse.

//centerX and centerY are the position of the center of the ellipse.

//Calculate a and b.

a = (max(lineBeginX, lineX) - min(lineBeginX, lineX)) * 0.5;

b = (max(lineBeginY, lineY) - min(lineBeginY, lineY)) * 0.5;

//Calculate the center of the ellipse and store its coordinates to centerX and centerY.

centerX = (lineX - lineBeginX) * 0.5;

centerY = (lineY - lineBeginY) * 0.5;

if (fill == FILL_ON) //This is equal to 'if (fill == 1)' because of the #defines at the top.

{

for (t = 0; t < 360; t += 0.1)

{

//Set the pen to the fill color and fill the ellipse.

setpen(R2, G2, B2, ALPHA2, SIZE2);

moveto(a * cos(t) + lineBeginX + centerX, b * sin(t) + lineBeginY + centerY);

lineto(a * cos(t) + lineBeginX + centerX, lineBeginY + centerY);

}

}

//The for loop for drawing the ellipse's edges.

for (t = 0; t < 360; t += 0.1)

{

//Set the pen to the edge color and draw the ellipse's edges.

setpen(R, G, B, ALPHA, SIZE);

putpixel(a * cos(t) + lineBeginX + centerX, b * sin(t) + lineBeginY + centerY);

}

}

EDIT: Fixed the bug with the ellipse's edges, see the picture below for how the edges look like now.

The example and the code have been updated, too.