Anti-aliasing inaccurate (how is the X update coming along?)

**eobet** · 08 April 2004, 03:41 AM

I believe this is my third topic describing an inaccuracy with Xara X (use search if you wish to see the others).

So, computers used to be a bit slower, and Xara might have had to cut corners in order to get it fast.

But today, they should be able to incorporate more accurate calculations, and still have the application feel fast.

Here's the current thing I'm working on. On the left side, I turned off anti-aliasing, and the meridian's color is correct, but on the right side, the color is somehow darker than it's supposed to be:

**eobet** · 08 April 2004, 03:41 AM

I believe this is my third topic describing an inaccuracy with Xara X (use search if you wish to see the others).

So, computers used to be a bit slower, and Xara might have had to cut corners in order to get it fast.

But today, they should be able to incorporate more accurate calculations, and still have the application feel fast.

Here's the current thing I'm working on. On the left side, I turned off anti-aliasing, and the meridian's color is correct, but on the right side, the color is somehow darker than it's supposed to be:

**eobet** · 08 April 2004, 03:43 AM

While I'm at it, this is a fun thing as well:

Look at this one. On the left side, I did Undo to get back to my original shape, and on the right side is the original, freshly loaded shape.

Notice how the colors suddenly are different!

No matter what editing operation I do, the color on the bevel suddenly changes, and no matter how I use the eyedropper, I can't replicate that color.

**Charles Moir** · 08 April 2004, 04:48 AM

Difficult to give any feedback without the .xar files so we can see it in more detail. Can you include them?

**eobet** · 04 May 2004, 11:48 PM

Sorry, I forgot to check these boards for a while.

Here is the first file. Try switching back and forth between anti-aliasing and lower details. The bug is that the once near-white lines become near-black with anti-aliasing on.

**eobet** · 04 May 2004, 11:54 PM

And here is the second file. Note editing the first shape in any way changes its color, and note how color picking from the already edited shape I included, yields the same color as the rest, even though it is clearly not.

**Charles Moir** · 05 May 2004, 03:27 PM

The reason for the first example - the lines appearing dark against the background is simply because the lines are really shapes and contain an outline that is the pale grey colour - but the inner shape is actually black. Select the longitude lines and simply click the 'no colour' to give it no fill colour at all. You'll see the lines now go to the expected colour, namely that of the 0.5pt outline. The reason this happens at very small scales is that the shapes and lines are well under a single pixel wide. So the anti-aliasing it blending the edges and a tiny, tiny amount of inner black fill along with the background all in less than a pixel - resulting in a colour that is a tad darker than the background. The more you zoom in, the more of the line width (stroke) is visible meaning it takes dominates the anti-aliasing blend and so result in the more correct colour.

So, in summary, we think it's working as we'd expect. You can easily make it the right colour simply by removing the black fill colour.

On the second point about the bevel, I'm not that I exactly understand what you're doing. Editing the first (by which I assume you means the on on the left) does not alter the colour for me. By editing I'm doing things like editing the shape, scaling etc. Obviously if I alter the color then yes, the color changes, but only as I'd expect. We have improved some aspects of bevel rendering in the new version (which is what I'm using) so perhaps wait until that comes out to see if it does what you'd expect (real soon now....)

**eobet** · 07 May 2004, 11:07 AM

The new X1 actually rendered the image better.

Turning off the fill color did work, as you said, but why would a fill color have any effect on a line? It doesn't use fills.

Regarding the second bug, I can no longer reproduce it in X1, so it was possible that it is fixed in one of the optimizations of the rendering engine, because it was probably a rendering error (since the color picker couldn't detect any difference in colors).

So, thank you for the reply!