grafx2. creating an isometric circle on a cube from all sides?

[Cybernetic]

hi guys. im having a hard time figuring out how to create an isometric circle like this http://www.wayofthepixel.net/pixelation/index.php?topic=6902.0 can grafx2 'skew' circles to the 30 degrees necessary to do this. i know how its done vector wise but the pixel method not so much...  surely there must be a certain method to do this. thanx

[ptoing]

What you can do is draw an iso square first and then fit a circle into that.

Also seriously, we are not here to teach you everything, put in some effort and read
http://code.google.com/p/grafx2/wiki/UserManual if you wanna learn how grafx2 works, and also how about doing some research on the web and/or this forum first before posting new questions indiscriminately.

http://pixel-zone.rpgdx.net/shtml/tut-isometric.shtml

Please in the future before posting a questions, try around yourself a bit, make your own research, only if you feel like you are totally stuck post in this section. Or better yet, make some actual pixelart and post it in the Pixel Art section for critique.

[Cybernetic]

ok. ill try to be more a bit more proactive. i was wondering why nobody was answering my questions, i guess cause they were beyond 'noob'

[yrizoud]

At first I thought it was about "how to draw an ellipse", then I thought it was "can we draw a rotated ellipse", but in fact it's the specific skewing as recommended by iso tutorial:
The page "Basic shape construction", says:

The side circles however, need to be drawn and then skewed to fit the face as the animation shows."

(See last image of page http://pixel-zone.rpgdx.net/shtml/tut-isometric4.shtml)

Grafx2 doesn't have a skewing tool (transform a rectangular brush into parallelogram), but you can use the brush distort tool :
- draw an ellipse with the right width & height
- draw the target parallelogram somewhere, as a helper
- grab the ellipse as a brush
- Brush options / distort : click and drag the 4 summits of your ellipse so that each one is at a corner of the parellelogram. Right-click to end the operation.

In any case, such operation is really not pixel-perfect; it will have the proportions right, but you'll still need to clean the outline.

[ndchristie]

DO NOT I REPEAT DO NOT USE THE PIXEL-ZONE ISOMETRIC TUTORIALS.

Whoever wrote them does not understand 2:1 isometric fully.  he loses a lot of compression in places, and gains some in others.  the square on which he defines the circle is not actually square, invalidating his form.

a real vertical square will end up about 88% as high as its undistorted width, or in perspective close to 125% of the distance covered (so if your tile block is 32px wide, then the height of the cube should be 20 pixels, *not* 16).



Here are some common cube sizes drawn in this method:



The astutue will notice that this is not 100% accurate - the value is actually a bit less than 125% (true ratio involves an arctangent), and the higher sizes should estimate accordingly - 1 pixel less starting at 32.  However, I keep the 5:4 method, as this ensures that all smaller cubes can tile on themselves to line up precisely with the larger ones, and that patterning can be achieved with relative ease.