I'm converting the cairo samples (http://cairographics.org/samples/
http://cvs.cairographics.org/cairo-demo/cairo_snippets/) to pascal.
I'm getting a runtime error 207 (invalid float operation in win32) in
two specific examples (arc and arc_negative). All other examples works fine.
Here's the converted code snippet (a compilable example is attached):
xc := 0.5;
yc := 0.5;
radius := 0.4;
angle1 := 45.0 * (PI/180.0); (* angles are specified *)
angle2 := 180.0 * (PI/180.0); (* in radians *)
cairo_arc (cr, xc, yc, radius, angle1, angle2); -> works fine
cairo_stroke (cr);
cairo_set_source_rgba (cr, 1,0.2,0.2,0.6);
cairo_arc (cr, xc, yc, 0.05, 0, 2*PI); -> works fine
cairo_fill (cr);
cairo_set_line_width (cr, 0.03);
//cairo_arc (cr, xc, yc, radius, angle1, angle1); -> uncomment and you
will get the error
cairo_line_to (cr, xc, yc);
//cairo_arc (cr, xc, yc, radius, angle2, angle2); -> uncomment and you
will get the error
cairo_line_to (cr, xc, yc);
cairo_stroke (cr);
The first two cairo_arc works fine. But the third and fourth not. The
later have the angle values equal.
I compiled the original code (c) and worked fine in the same system.
Here's the c code:
double xc = 0.5;
double yc = 0.5;
double radius = 0.4;
double angle1 = 45.0 * (M_PI/180.0); /* angles are specified */
double angle2 = 180.0 * (M_PI/180.0); /* in radians */
cairo_scale (cr, width, height);
cairo_set_line_width (cr, 0.04);
cairo_arc (cr, xc, yc, radius, angle1, angle2);
cairo_stroke (cr);
cairo_set_source_rgba (cr, 1,0.2,0.2,0.6);
cairo_arc (cr, xc, yc, 0.05, 0, 2*M_PI);
cairo_fill (cr);
cairo_set_line_width (cr, 0.03);
cairo_arc (cr, xc, yc, radius, angle1, angle1);
cairo_line_to (cr, xc, yc);
cairo_arc (cr, xc, yc, radius, angle2, angle2);
cairo_line_to (cr, xc, yc);
cairo_stroke (cr);
Here's the c header (arc):
cairo_arc (cairo_t *cr,
double xc, double yc,
double radius,
double angle1, double angle2);
Here's the pascal header (cairo.pp):
procedure cairo_arc(cr:Pcairo_t; xc:double; yc:double; radius:double;
angle1:double; angle2:double); cdecl; external LIB_CAIRO;
I'm using fpc220 under Ubuntu 07.04
Anyone has a hint on whats going on?
Luiz
program cairobug;
uses
cairo;
const
IMAGE_WIDTH = 256;
IMAGE_HEIGHT = 256;
procedure do_arc(cr: PCairo_t; width, height: Integer);
var
xc: Double;
yc: Double;
radius: Double;
angle1: Double;
angle2: Double;
begin
xc := 0.5;
yc := 0.5;
radius := 0.4;
angle1 := 45.0 * (PI/180.0); (* angles are specified *)
angle2 := 180.0 * (PI/180.0); (* in radians *)
cairo_scale (cr, width, height);
cairo_set_line_width (cr, 0.04);
cairo_arc (cr, xc, yc, radius, angle1, angle2);
cairo_stroke (cr);
(* draw helping lines *)
cairo_set_source_rgba (cr, 1,0.2,0.2,0.6);
cairo_arc (cr, xc, yc, 0.05, 0, 2*PI);
cairo_fill (cr);
cairo_set_line_width (cr, 0.03);
//cairo_arc (cr, xc, yc, radius, angle1, angle1); //-> uncomment and you will get the error
cairo_line_to (cr, xc, yc);
//cairo_arc (cr, xc, yc, radius, angle2, angle2); //-> uncomment and you will get the error
cairo_line_to (cr, xc, yc);
cairo_stroke (cr);
end;
var
cr: PCairo_t;
surface: Pcairo_surface_t;
begin
surface := cairo_image_surface_create (CAIRO_FORMAT_ARGB32, IMAGE_WIDTH, IMAGE_HEIGHT);
cr := cairo_create (surface);
cairo_save (cr);
do_arc (cr, IMAGE_WIDTH, IMAGE_HEIGHT);
cairo_restore (cr);
cairo_surface_write_to_png (surface, 'testcairobug1.png');
cairo_destroy (cr);
cairo_surface_destroy (surface);
end.
_______________________________________________
fpc-pascal maillist - fpc-pascal@lists.freepascal.org
http://lists.freepascal.org/mailman/listinfo/fpc-pascal
