Bug / Undesirable behavior in thickLineRGBA()

SDL Development
1

Hello,

I have an application I wrote that draws a line between two points and
allows the user to move the points around. If the user moves the
points around such that they are directly adjacent to each other the
call to thickLineRGBA() will freeze the program. I glanced at the
code for thickLineRGBA and the problems seems to be in.

void _murphyWideline(SDL_gfxMurphyIterator *m, Sint16 x1, Sint16 y1,
Sint16 x2, Sint16 y2, Uint8 width, Uint8 miter)

For example: this call would cause the program to free abruptly:

  x1 = x2 = y1 = y2 = <same_value>
 thickLineRGBA(screen, x1, y1, x2, y2, thickness , r,g,b, 255);

This isn’t really a big deal but it does require the user of the
library to add a special check for this case which may not be
obviously realized.

Btw I’m running SDL_gfx-2.0.22 .

Thanks,

Aaron–
Aaron O. Rosen
Masters Student - Network Communication
306B Fluor Daniel

2

Hello,

That does sound like undesirable behaviour. However, SDL_gfx isn’t
officially part of SDL. Perhaps you should try contact the author?

Here are some places to start:

http://www.libsdl.org/libraries.php?order=name&category=-1&completed=0&os=-1&match_name=SDL_gfx&perpage=25
http://www.ferzkopp.net/joomla/content/view/19/14/

Regards,
– Brian.On 2 December 2011 06:02, Aaron Rosen wrote:

Hello,

I have an application I wrote that draws a line between two points and
allows the user to move the points around. If the user moves the
points around such that they are directly adjacent to each other the
call to thickLineRGBA() will freeze the program. ?I glanced at the
code for thickLineRGBA and the problems seems to be in.

3

A bugfix is now checked into the SDL_gfx SVN repository on SourceForge -
thanks Aaron for the bug report.On 12/3/11 4:45 PM, Brian Barrett wrote:

Hello,

That does sound like undesirable behaviour. However, SDL_gfx isn’t
officially part of SDL. Perhaps you should try contact the author?

Here are some places to start:

http://www.libsdl.org/libraries.php?order=name&category=-1&completed=0&os=-1&match_name=SDL_gfx&perpage=25
http://www.ferzkopp.net/joomla/content/view/19/14/

Regards,
– Brian.

On 2 December 2011 06:02, Aaron Rosen wrote:

Hello,

I have an application I wrote that draws a line between two points and
allows the user to move the points around. If the user moves the
points around such that they are directly adjacent to each other the
call to thickLineRGBA() will freeze the program. I glanced at the
code for thickLineRGBA and the problems seems to be in.

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