Thanks for the explanation.
Now I need to comprehend it :)
On 11 сент, 20:28, Mike Reed <[EMAIL PROTECTED]> wrote:
> /* oops, the rect example I gave is for (0,0) (2,0) */
>
> On Sep 11, 2008, at 9:27 AM, Mike Reed wrote:
>
> The general confusion is that the android graphics geometry is center-
> line based, and consistent at all matrix transformations, while J2ME
> linedrawing is more "pen" based.
>
> As an example, when android draws a line, it basically constructs a
> rectangle about the line, by moving parallel to the line by 1/2 the
> strokeWidth. If there is no fancy Join (e.g. Square or Round), no
> outset is performed on the line's ends. So for the line (0,0) (0,2),
> it constructs the rectangle
>
> // assuming the strokeWidth is 1.0
> left = 0
> top = -1/2
> right = 2
> bottom = 1/2
>
> and then tries to fill the rectangle, using the standard of rounding
> each coordinate to an int via (int)(coord + 0.5) // for positive coords
>
> That said, in your example, the strokeWidth is 0, which is a special
> value meaning hairline. This is pretty close to 1.0, but will draw
> slightly differently at times, but much faster. (aside: hairline
> stroking always draws 1-pixel wide, regardless of the matrix on the
> canvas).
>
> Stroking rectangles in hairline mode does a little extra work to be
> nice to try to hit all of the corners, even if the normal hairline
> drawLine path would have missed it.
>
> But back to center-line geometry. The upshot really is, if you want to
> trivially predict what pixels will be hit for stroking, put your
> geometry on 1/2 pixel boundaries. Then when I outset by 1/2 the
> strokeWidth, the center-line pixel will always get hit.
>
> mike
>
> On Sep 11, 2008, at 9:12 AM, sahn0 wrote:
>
> Yes, p is Paint object set up as follows:
>
> Paint p=new Paint();
> p.setColor(0xFF800000);
> p.setStyle(Paint.Style.STROKE);
>
> Style.STROKE is needed for drawRect to actually draw rect, issue with
> right-bottom pixel shows itself independently of Style.
>
> On 11 сент, 19:48, Mike Reed <[EMAIL PROTECTED]> wrote:
>
> > Might be a bug. Can you put a more complete code snippet (including
> > how the paint (p) was setup) into the bug?
>
> > thanks,
> > mike
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google
Groups "Android Developers" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to
[EMAIL PROTECTED]
For more options, visit this group at
http://groups.google.com/group/android-developers?hl=en
-~----------~----~----~----~------~----~------~--~---
