Weird bug...

[Anonymous]

Hello everyone!

Please excuse me if I'm asking a question that has already been answered and/or this topic duplicates an existing one. The Search function didn't help, and I just don't have enough time to browse through all 30 pages of the Rendering section.

I'm currently working on a 3d model of an appartment building. This is actually the first time I use ArchiCAD (treat me as a newbie please )and I'm learning as I go. So far I didn't have problems, thanks to ArchiCAD's extensive help pages, this forum's discussions and various other websites; yet today I ran into something that I just can't figure out how to solve.

I use two types of materials for the walls, each with different colour and shader settings. They are actually modified duplicates of the default "Surface-Whitewash" material, which itself is modified to the wall colour and used for the floor slabs.

The sand-yellowish walls (see attached images) are set to a "Surface-Whitewash" duplicate material with "Rough" displacement, and the orange-brownish walls are set to the other duplicate which has similar settings. The top sides of the floor slabs are set to the default "Surface-Whitewash" material (no displacement) with either of the two duplicates used for sides and bottom, depending on the slab's position.

Now, the problem is this: when I render a high-resolutoin image with LightWorks, it just "skips" a certain area of the front wall and leaves it blank except for the colour, without applying the shader settings I selected for that material (most obviously the displacement settings which should be "Rough"). The rest of the walls are OK. (look closely at attached closeup_large.jpg)

The funny part is that when I lower the resolution of the rendered image this problem no longer appears, and all the walls are displaying as they should (see attached closeup_medium.jpg).

The border between shaded and non-shaded area does not correspond to any border or intersection between two walls or other objects that could cause any discrepancy in materials. The zones seem to be just randomly picked; however, they are the same each time I render an image, no matter what angle or zoom.

Could this be due to insufficient system resources that don't allow proper rendering of a high-resolution image? I'm running ArchiCAD 9 on a 2.8 GHz laptop with ~ 1GB RAM, Win XP SP3. I don't think it is, because the same problem appears on my home PC, which is 1.5 GHz 1.19 GB RAM, Win XP SP2 (with the same portions of the walls appearing blank).

I do actually need to render a high-resolutoin image (as far as I remember my client wants an image posted on a billboard) so please tell me if I can do something to fix this. Thanks in advance, all help will be appreciated.

[Anonymous]

Here's the smaller image as I evidently can't attach more than one image per message.

[Anonymous]

What resolution are you using for your images?

Dwight suggest that "150 dpi - 180 dpi is the practical limit for Archicad output to inkjet printing when making photo-like images"

Link to Topic.

[Dwight]

try a different sun angle.

[Anonymous]

As far as I remember these images are at 72 dpi. But does it have anything to do with printing? It just doesn't display it on the screen...

Thanks for the suggestion Dwight, I'll try a different sun angle tomorrow... I'll be away for a while

[Anonymous]

A different sun angle didn't help, and neither did changing the dpi setting to both higher and lower.

Any other suggestions will be greatly appreciated...