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satyria · Familiar Face Joined: 25 Feb 2008 Posts: 18

GTK, Cairo, filling routine

Hello, maybe it is just a small mistake, but I have the following:

When I define an object in cairo and then fill it wants to produce a transferees result(shadow?).

Here my example:

First example shows in red, as I have it in Cairo with cairo_move_to and cairo_line_to have defined (without cairo_fill). The second example shows, when it was filled.

I'd like it if the entire area is filled.

Commands:

Code: (Plaintext)
1 2 3 4 5 6 7 8 9 10 11 12	cairo_set_antialias(cr, CAIRO_ANTIALIAS_NONE); cairo_set_line_width (cr, 1); cairo_set_fill_rule (cr, CAIRO_FILL_RULE_EVEN_ODD); cairo_move_to(cr, x, y); cairo_line_to(cr, x, y); cairo_fill (cr); cairo_stroke (cr);

Last edited by satyria on Fri Sep 26, 2008 12:20 pm; edited 1 time in total

satyria · Familiar Face Joined: 25 Feb 2008 Posts: 18

Hello,

here is a programm with the normal routines

Code: (C)

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{
cairo_t *cr;
gint x, y;
gint w, h;

x = da->allocation.x;
y = da->allocation.y;
w = da->allocation.width;
h = da->allocation.height;

//The first Circle:

cr = gdk_cairo_create(da->window);
cairo_set_antialias(cr, CAIRO_ANTIALIAS_NONE);
cairo_set_line_width (cr, 1);
cairo_arc(cr,50,50,40,0,360* (3.1415 / 180.));
cairo_stroke(cr);
cairo_destroy(cr);

cr = gdk_cairo_create(da->window);
cairo_set_antialias(cr, CAIRO_ANTIALIAS_NONE);
cairo_set_line_width (cr, 1);
cairo_arc(cr,50,50,39,0,360* (3.1415 / 180.));
cairo_stroke(cr);
cairo_destroy(cr);

//The second filled circle:

cr = gdk_cairo_create(da->window);
cairo_set_antialias(cr, CAIRO_ANTIALIAS_NONE);
cairo_set_line_width (cr, 1);
cairo_arc(cr,150,50,40,0,360* (3.1415 / 180.));
cairo_stroke(cr);
cairo_destroy(cr);

cr = gdk_cairo_create(da->window);
cairo_set_antialias(cr, CAIRO_ANTIALIAS_NONE);
cairo_set_line_width (cr, 1);
cairo_arc(cr,150,50,39,0,360* (3.1415 / 180.));
cairo_fill (cr);
cairo_stroke(cr);
cairo_destroy(cr);

return TRUE;
}

and the picture:

whence come the empty place?

Greeting Satyria

satyria · Familiar Face Joined: 25 Feb 2008 Posts: 18

Hello,

The correct command is: "cairo_fill_preserve"

Satyria

dreblen · Posted: Fri Sep 26, 2008 3:53 pm Post subject:

so you got it fixed?

also, I'd like to point out that you don't need to destroy your cairo context after each stroke, you can use the same one throughout the entire
function and then destroy it at the end.