I am using CoreDraw to generate vector icons which have to be "transformed" to bitmaps (Png) in different sizes (16x16, 20x20, 24x24, 32x32, 48x48,... 256x256, 512x512).
When doing so, I found three problems which I have to deal with:
1. Image sizes don't match with the pixel size in the export dialog, e.g. 16x16 may generate a 15x17 bitmap (the vector object is a square and "keep aspect ratio" is unchecked to force a 16x16 size)
2. Text is in low quality, especially the kerning is awful (the text ICON may look like IC O N on the exported image)
3. "Alpha Layer holes" - objects wich edges are side by side get exported with correct color values but the values for the alpha layer isn't set to opaque, so the exported image looks like a swiss cheese in certain situations.
Does anyone have seen these problems and know how to deal with them?
There's a real art to drawing icons. I don't think you can expect to draw one piece of vector artwork that will export a good looking icon at every size you want.
Here's a CDR (zipped) with a Word icon drawn at two sizes, each drawn individually and aligned to the pixel grid and the two sizes exported as PNGs.
Word Icon.zip
Thanks for your help, would like to have a look into your example but my CorelDraw app can't load it ( I have 23.1 installed because I don't like subscriptions) ;-)
Could you save the CDR file it in a format for CorelDraw 2021?
Here's a version of the CDR backsaved to v21.
Word Icon v21.zip
Thanks a lot (also to all others here), this is a big step forward now...
As you have said already, the pixel preview does help a lot - so you can see what you will get when exporting. After playing around with your example, I believe the following strategy will create fine results:
- Working with pixels only (for object transformation, line width, etc.)
- Resizing and moving have to be done for every single object - doing that for a group of objects will do the same like the routine seen in the export module
- Don't use export for scaling up/down to a pixel image - the routine seems to calculate with low precision and produce low quality images
Working with pixels within CorelDraw is new for me, so I have another question: how to change an object to snap it's nodes to the center of a pixel? When creating an object with an outline (1px width) I'd need to move the nodes from the pixel corners to the pixel center. I'd need something like a grid size of 0.5 pixels
Glad to hear you seems to have found a way to make it better.
Puffolino said:how to change an object to snap it's nodes to the center of a pixel?
I think it depends on what version you use.If memory serves, it used to be possible in older versions but you cannot do it in versions 2020 or 2021 for example, and I think it was removed because it was too easy to accidentally create half pixel positions.Luckily, the ability to snap to grid center has been reintroduced and you should be able to do so in version 2023.It can still be a bit tricky to get it right though, and the workaround (which fortunately also works in 2020 and 2021) is to nudge with the arrow keys.As long as you use the Pixels view mode, each press on one of the arrow keys will move the object 0.5 pixel.
Glad this has helped a bit.
Apart from what Ronny has said, you can always type the exact location/dimensions in the Property bar.