Messages

1

[Max] Bug Reporting / CoronaTileMap and Real-World scale.

« on: 2025-03-05, 11:21:45 »

There seems to be something wrong with the Tile Map and Real-World Scale.

I want to use RWS to set both the size of the tiles, and the size of the teture displayed on each tile. I use RWS on all geometry per default.

I set RWS in the Tiles map, and set the tile size to 150x150mm. I plug in a Corona Bitmap in the Tile Color, and set the Bitmap to RWS 150x150mm. You would expect to have one repetition of the bitmap per tile, right? Wrong! I need to set the bitmap to a 1x1mm to make it 150x150 in the render!!

It appears to be some kind of mistranslation of the tiling parameter from the bitmap.


Also, I thought I would bypass the issue by setting the Tile Map to UVW chnl 2 and the Bitmap to chnl 1. That did not work at all - and the bitmap instead used the chnl 2 mapping.

2

[Max] I need help! / Crash when rendering Physical camera - no problems rendering Perspective view

« on: 2025-03-03, 09:41:25 »

I'm trying to render images of my project, but almost all attempts fail with an "unhandled exception" crash as soon as render starts. It's a project made in Corona 10 (if I remember correctly), but I've gone to great lenghts to not use the old Physical Camera objects, or old scenes,  but instead created new cameras in a new file, then merged the old model into that file.

The crash only seems to occur when I render a camera view - if I switch to Perspective, it renders without problem.

I've tried with or without displacement, but it makes no difference. There are ForestPack and RailClone objects in the scene, but that doesn't seem to really matter either - they render fine in perspective view.
To make matters worse, one view rendered in camera, but only when Vertical Shift was turned off. Thought that was the problem, but no; the other view crashed regardless.

I'm at wits' end, and I'm about to downgrade to Corona11 to see if it makes any difference. Any other ideas?

3

[Max] Resolved Bugs / Re: Volume Material "Inside Volume" setting not working correctly.

« on: 2023-02-03, 10:51:44 »

Alright! Will give it a go.
I must be mistaken then (and my colleagues as well). Clearly remember being able to produce nice fog (with noise) when inside a volume, without using global volume material. It's a pain setting up an animation where the fog volume has to move with the camera.

Feature request removed. Will make a separate thread about that once I've tried Corona 10.

4

[Max] Resolved Bugs / Volume Material "Inside Volume" setting not working correctly.

« on: 2023-02-02, 23:56:56 »

I haven't used the volume material to create fog in a while, but the behaviour isn't what I remember. Maybe this is a bug.

When using a volume material, it can either be assigned globally (in the render setup) or locally to an object. The "On Surface" mode is quicker, but only works when the object containing the volume effect is seen from the outside. However, when setting it globally, it works no matter the camera placement. So far so good.

The other option is to use the "Inside Volume" setting, which is significantly slower (more than twice the render time in these examples!). It works as expected when set globally, albeit slow. It works when seen from outside the object when used locally. When seen from inside the object it does not render correctly! Afaik, it was previously possible to place the camera inside the volume, and render correct volume effects. Is this a bug??

It's also interesting to see the difference when applying noise. With "On Surface" the result looks... extremely poor. With "Inside Volume" it looks great. I remember it as being a lot more similar.

The scene here is a simple box (gray CRN PhysMat) with some holes in the roof, a daylight with CRN-sky, and an editable poly object containing the fog.

Win 11, CRN 9 HF1, Max2023

5

[Max] I need help! / Re: Corona Converter - unable to process Vray materials/maps

« on: 2022-10-19, 13:26:34 »

Great! Problem solved. Had no idea that page existed.
Still, having to install all of Vray just to get the converter to work seems rather inconvenient. Wish the converter would work without Vray installed.

6

[Max] I need help! / Corona Converter - unable to process Vray materials/maps

« on: 2022-10-19, 10:35:59 »

The converter is unable to read/convert materials and maps from Vray unless you have Vray installed.
In the past, this issue was solved by installing the Vray demo, and even after it expired, the converter could use it to read Vray materials.

Since Chaos changed their policy, Vay is now a one-time trial, and it's not possible to download it again once your trial has expired.

This poses a problem when you update 3dsmax or get a new computer, since you cannot download Vray again. I see no other option than having to buy the full version of Vray... which really isn't worth it to me. This does imo defeat the purpose of the converter, rendering it useless.

Do you see any other solution? I think Chaos ought to be able to include the files necessary to make the converter fully functional without having to install Vray.

7

[Max] I need help! / Re: Layered Material Displacements in Corona 3

« on: 2020-03-07, 00:19:34 »

Agreed. It would help A LOT.

If this can be done fairly easily "by hand", surely Corona should be able to apply the same fix automatically "under the hood"?

8

[Max] I need help! / Re: Corona 5 - 2.5D Displacement on Curves

« on: 2019-11-19, 15:20:39 »

I've tried with and without noise mod; with different textures; RWS and not - it persists. Even tried world size displacement.

But I think it's strange you get this obvious repeating/tiling pattern. With the old displacement you could just lower the quality - sure, you'd lose detail, but you wouldn't get artifacts like this. If you can reproduce it, I hope you can sort it out.

9

[Max] I need help! / Re: Corona 5 - 2.5D Displacement on Curves

« on: 2019-11-19, 14:00:00 »

Hey Matsu, what is the topology of your plane? Is it equally subdivided, can you please provide a wireframe?

It's a plane primitive 3x3m, 30x30 division (+Noise modifier Scale=20 Strength Z=60mm) - so 100x100mm squares. Adding wireframe.

You need to set lower screen size in 2.5D displacement, or higher in classic one, to get comparable results. If i'm not mistaken, the ratio is about 1:1,5 So 1px classic displacement, should have about the same quality as 0,67px 2.5D displacement.

Adding comparison on 0.5px. The artifact is still there, but not as pronounced.

10

[Max] I need help! / Re: Corona 5 - 2.5D Displacement on Curves

« on: 2019-11-19, 11:37:43 »

I'm adding this to the thread, even though this isn't strictly about curves, but rather about the 2.5D displacement in general.

I just tried setting up a simple textured lawn thing, and noticed some strange artifacts. Tried to see where it was coming from, and I realised it was coming from the 2.5D displacement. Tried changing to 3D and it's a huge difference.
It's just a simple JPG file, loaded with CoronaBitmap at gamma 1.0 and the bitmap size is bigger than the sample plane, so no repetition there. Displacement is at 1px in both cases.

Help/suggestion?

I think I will consider using 2.5D only in cases where memory is an issue, since the look is significantly worse. :(

11

[Max] I need help! / Re: [solved] CoronaMultiMap and Displacement

« on: 2019-10-08, 12:10:45 »

we are working on a fix.

How is it going? ;)

I am right now designing a material, and was going to randomize displacement with "element" mode, but wasn't able to. Using "MaterialByElement" kind of works, but it then appears as if the Gamma Randomization has no effect. It would be absolutely great if this worked. Thanks.

12

[Max] Resolved Feature Requests / Re: Like"FStorm GeoPattern" corona pattern

« on: 2019-02-11, 16:37:33 »

++++++1 for geopattern

13

[Max] General Discussion / Re: Corona Distance Shader slows scene to a crawl

« on: 2019-02-11, 16:34:15 »

a checkbox for rendertime only would be great, but instead of a global setting, it should be set per distance map.

Agreed! I don't really use distance map due to this reason.

14

[Max] General Discussion / Re: Autobump concerns and 2d displacement ala vray

« on: 2019-02-11, 16:31:20 »

I was really stoked when I read about the displacement improvements that came with the latest version. However, I've tried it out some now, and I'm actually bit disappointed.

I'm sure the latest fix has improved the look of irregular disp-maps, but the way I use it (in archviz) is to produce pronounced details on buildings, which are almost always sharp and regular.
In the image I use the same basic brick texture, but on some parts of the facade, the architect wants a striped pattern. Since the meshing of the displaced areas is triangulated and random, the edges get very jagged, and the shadows look... really bad.
This kind of thing worked a lot better with Vray's 2D displacement. (I don't have any experience from using Fstorm.)

In the image, the displacement is set to Screen 1.5px, but many times, the scenes are too large and too complex to use such a small value. (I'd love to be able to increase it per object, or even use Screen and World on different objects!)


A possible solution I could think of is that Corona considers the displacement map's contrast to decide where to add triangles. So, if there's a sharp contrast between the pixels in the map, Corona adds more triangles, and vice versa. Adaptive meshing based on dispmap contrast. Edit: Did a quick test, and noticed it already does this. Added another image where I used a checker map to displace a tessellated cube. It shows the problem, and how displacement tries to solve the issue. 1px displacement in this render, but artefacts remain no matter the setting.
One could also think that the meshing uses some kind of "loop detection" to follow the shapes of the dispmap.


Another thing I been thinking about is the option to use "displacement LOD" - an option to skip displacement if the the displaced geometry is too small (too far away). Right now, displacement can really destroy the look of displaced mesh that is too far away from the camera.
The only solution now is using different materials for different shots of your scene, but is just too cumbersome to be a practical solution, and using World scale just isn't an option due to memory use.


I really hope you keep working on this. For me, it's one of the areas where Corona is lacking compared to other renderers.

15

[Max] I need help! / Re: IOR for unfinished wood?

« on: 2018-08-17, 13:59:19 »

Make it really rough (like 0.25 or something) and add a bit of bumpmap. That usually works for me, anyway.