View Full Version : Ways To Combat Moire Pattern ?

04 April 2005, 03:13 AM

If you make a tin roof ( texture ) and zoom out you tend to get a moire pattern, whats the best way to keep the moire pattern from happening ?

I've tried breaking the pattern up, and adding dirt, wear etc but it seems to have no affect.

Any tips ?

04 April 2005, 07:03 AM
Enlarge the pattern.

Increase image resolution.

Blur the pattern, or otherwise soften it.

Lower the contrast of the pattern.

04 April 2005, 08:37 AM
effect, not affect.

as far as i understand it, moire pattern is often a result of texture filtering, and it's really a hardware issue. isn't it? or no. maybe not.

04 April 2005, 01:43 PM
turning on supersampling will most likely help as well.


04 April 2005, 02:28 PM
isotropic sampling solves this doesn't it?

04 April 2005, 03:25 AM
The challenge is partly in the understanding. Moiré patterns are a function of screen effects and the interaction of grid and line patterns. Take two screens off your windows and look through both at once, while rotating one of the screens, and notice as it approaches the narrow angles between them, you will get great moiré patterns. Same thing with multiple layers of sheer translucent fabric. Now how does this relate....??? You will get moiré patterns whenever viewing some combination of line screens at close angles, and this includes the screen that you are looking at right now, which is a pattern of lines, yeh, look closely.... so when you zoom in and out on an image you will notice that the pattern shows up at one point in the zoom, but not at another, or when your model or camera moves around the subject, or when the combination of procedurals used in the creation of textures get to be too close in angle. This is the reason that the screen angles on commercial CMYK printing are set at the greatest degree of rotation from each other. Opening the patterns a bit can help because it is most noticeable with fine patterns of close lines, overlaid at narrow angles. I takes some playing around once you get the concept, including changing the shot angle.

04 April 2005, 04:51 PM
You haven't told us if it's a real time application or a render! If it's a render, turn on supersampling, as suggested. If it's real time, you'll have to check your hardware/display settings for filtering/supersampling. The moiré is caused by the tin roof pattern overlapping your screen's dot or line pattern.

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04 April 2005, 04:51 PM
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