Messages

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[Max] I need help! / Re: Any better ways to use a single HDRI sphericals map both as env and lightning?

« on: 2025-05-17, 14:58:48 »

This particular HDRI doesn't seem to be calibrated correctly. If you place a Corona Sun next to the sun in the HDRI and check their RGB values, you will see that the Corona Sun is about 2x stronger than the one in the HDRI. I don't think there was some cloud layer or haze in the air while capturing that HDRI, it looks clear. The sunlight intensity on the 3D objects appears much lower than for example on the church facade in the image. Note that this HDRI is provided by a 3rd party vendor.

Well , measuring the pixel values a great tip!
i first had to match the hdri's sun angle
using corona slect map, alternating with corona's sky map
i lined up them up so that the shadow cast by the corona sun   is almost the same as the hdri's...
vs

i created a CShading_RawComponent just to measure the brightness value
measured the ratio between light and shadow for the corona's sun which was 10:1 so the tip of the vertical box was ~50 and the shadow cast by that box was ~5,

so i changed the curve of the hdri to match that ratio of 10:1
so got this... monkey brain style



i think i can get away with this method for a while.

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[Max] I need help! / Re: Any better ways to use a single HDRI sphericals map both as env and lightning?

« on: 2025-05-16, 15:30:49 »

Unfortunately, there is no standard for the way HDRIs are set up, so you'll find some work for background and lighting without needing separate adjustments, and some won't. Loading the HDRI once and then just passing it direct into one place, and through a color correct in the other, is the easiest solution, and will always be required in some situations due to this variance in how HDRIs are created and set up :)

Thank you so much for the explanation—now I can tweak the settings with peace of mind.

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[Max] I need help! / Re: Any better ways to use a single HDRI sphericals map both as env and lightning?

« on: 2025-05-16, 12:49:59 »

So this is a common issue?

I always assumed the HDRIs I was using were incorrectly tone-mapped or something, and I ended up constantly fiddling with them because I didn’t really understand what was going wrong.

Now I just want to make sure none of my settings are causing the problem.

I really admire the Corona materials and overall rendering quality—it always feels like everything that comes from the Corona team is well-calibrated and physically accurate. So I decided to test this using an HDRI directly from Chaos Cosmos: **"HDR map 723"**.

Here's a screenshot of the HDRI I used:
\

And these are the settings I used in the environment slot:


I don’t think the scene should be coming out like this. I can clearly see shadows being cast from the sun position in the HDRI, so the directionality looks correct. But with all settings at default, is it really supposed to look like this—so bright?

It would be wonderful if someone could say, "Hey, you're doing this part wrong. Change this setting, and it’ll fix the discrepancy between the lighting and the visible background." That’s exactly the kind of clarity I’m looking for.

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[Max] I need help! / Any better ways to use a single HDRI sphericals map both as env and lightning?

« on: 2025-05-16, 10:43:29 »

Just to clarify,
I'm looking into whether there have been any improvements in using an HDRI as both the background and lighting source—without needing to create a separate exposure-adjusted instance for the visibility override.

Ideally, I'd like to use a single HDRI map that I can tweak and control for both the environment lighting and the background. But when I try to do that, I run into this issue:

In the past, I’ve relied on LightMix and multiple environment setups to manage this, but I’m wondering if there’s now a more efficient or streamlined method.

I'm actually fine with how the environment looks—I just want both the environment and the mesh to be lit consistently using the same map.

Right now, the workaround I use is to create a second instance of the HDRI: one for direct visibility (the background), and one for environment lighting. I boost the background version by +2 and reduce the environment version to -5.5 to get this result:


But I really wish there were a better solution for this in 2025.

5

[Max] Feature Requests / Re: "Corona Slicer Exclude" modifier on meshes

« on: 2023-10-31, 08:11:34 »

yes, this was purely a practical suggestion (merely selecting the object or group and without waiting for any menus to reload and solving the isssue on the spot) as the complexity of scene are getting out of hand and whatever practical solutions i get is more than welcome, that is why my suggestion. From the reply , i can see that i should not get my hopes up due to density of the to-do-list of corona,

Thanks for the consideration, or at least the response of acknowledgement,

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[Max] Feature Requests / "Corona Slicer Exclude" modifier on meshes

« on: 2023-10-26, 03:40:20 »

 Hi,
Instead of excluding a specific mesh, from a slicer applied mesh, by diving in to the slicer's material's exclude list, can be there an alternative like a "Corona Slicer Exclude" modifier (much like an extrude modifier).

benefits that i can imagine right now is mainly "Practical usage": as one would just have select the objects to be excluded and add the modifier, toggleable on/off, also as the exclude list creates a dependency when merging to other scenes and ties the excluded objects to the new scene mostly unnecessarily.

7

[Max] Feature Requests / Re: Disk lights when using directionality > 0.1, gets occluded

« on: 2023-10-24, 23:01:54 »

so overall,  despite me misinterpreting the problem, not reading very carefully the responses, i got the solution i needed , I LOVE CORONA and thank you for creating and supporting it.

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[Max] Feature Requests / Re: Disk lights when using directionality > 0.1, gets occluded

« on: 2023-10-24, 23:00:23 »

Can you provide a simple test scene? Not heard of this before - also, are you sure it is occluded, that is, it no longer casts light into the scene? Not just that it renders black (if so, is "prevent black appearance checked"? and if so, is this when viewed directly or when in refractions/reflections?)

after reading your invaluable reply,  i tried "prevent black appearance" which was already checked and as it did not fix the black appearance, i went ahead and prepared the scene, but later that night  tried enabling back the "occlude other lights" option(which was a no-go for me as i always had to fake the position of the lights away from the ceiling and that option was causing shadows on the ceiling due to being away from the ceiling ) anyways,, they were not black anymore.

So overall i think your answer was the simplest solution to this problem.

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[Max] Feature Requests / Re: Disk lights when using directionality > 0.45, gets occluded and not visible

« on: 2023-10-24, 21:09:34 »

I am sorry but i have misinterpreted the problem , it was not the light rays that were blocked, it was the visibility of the "disk light" affected instead.

in the scene i have shared, The disk light is set to be "directly visible" and camera is 90 degrees perpendicular to the ground.

directionality= 0.45

and disk is clearly visible, no problem.

increase the directionality to 0.46 and the disk is still visible but a semi transparent and faded.

increase it more and the disk is semi transparent more
at directionality 0.5, and it s now black.

but if you modify the camera upwards towards the disk, it becomes visible and white again unless the directionality is below 0.50, it gets black no matter what angle you look at it if dir. is >0.50

So Both standard camera and corona camera has this behavior.

Maybe i should post this as a bug fix but i am not sure if this was physically more correct somehow...

10

[Max] Feature Requests / Disk lights when using directionality > 0.1, gets occluded

« on: 2023-10-24, 09:01:11 »

 Hi,
When using corona disk light with directionality above 0.45, the disk light despite being below the ceiling mesh and supposed to be clearly visible and not occluded by the ceiling mesh, gets occluded. So i always have to move the disk light 4-5cm away/below the ceiling so it does not get occluded by the ceiling mesh, but this results in floating lights.

It seems, as directionality  increased on the disk light, the disk light's ray origin point is moved on the opposite direction of rays casted and this results in the rays get blocked by the mesh despite the light's placeholder free from the occluding mesh.

I am asking for a corona light option that will prevent this behavior so that i can place light directly beneath the ceiling mesh and not care about floating spot lights or a suddenly darker scene with occluded spotlights.

That would be very practical , you know...

thanks for the consideration.

11

[Max] I need help! / Re: Want to be able to watch youtube videos while rendering but

« on: 2023-02-20, 16:20:32 »

I have the same CPU and i can watch YT videos without problems while rendering (all cores enabled). The problem must be somewhere else. What typical resolution videos you are watching in YT. What version of 3ds Max and Corona you are using? Also what's your browser? Is it up to date? Maybe some plugins are causing video playback choppiness? If you try to play local video file with some media player, does it play choppy as well?

I am on a triple FHD displays plugged in to a single GTX 970 3.5/4GB GPU, i know the GPU is very much dated however, it just bugs me that the issue only occurs when rendering. I will try other browser, also do VLC video playback and come back soon

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[Max] I need help! / Want to be able to watch youtube videos while rendering but

« on: 2023-02-20, 15:04:07 »

 Hi!
I know i sound amateur but yeah i do watch youtube videos while rendering stills and i wish i was able to do it without video becoming choppy... My CPu is an 5950x with 64gb ram and i am having the Core count on -2 (it should be 4 threads free since core=2 thread).

ı check my gpu Video memory and it s  on limit but the thing is, choppiness occur only when rendering , so wondering if there is a way i can have proper video playback while rendering? I disabled bloom+sharpenning+denoising in the VFB but still the choppiness persist while rendering.

Any suggestions other than watching the videos somewhere else or not at all,
thnx

13

[Max] Feature Requests / Smart texture shader meant for wood textures

« on: 2022-10-28, 01:57:22 »

 Normally, i would not ask this feature in a "render" plugin's forum but over the years, corona introduced such niche features that i said why not!, this would save loads of time with many much like the UV Randomizer, Multimap, round edges  and so on....

The shader i want to see corona team bring to life is a texture orientation shader, which would automatically rotate/orient  the uv of a texture so that the longer edges of a polygon would define the orientation. This would be very useful as it would as it would be automatically useable on use it on roads , woodwork of the furniture, Ivy leaves etc...  A polygon's UV would be automatically aligned along the longer edges

14

[Scatter] Feature Requests / Chaos Scatter, scattering on scattered objects.

« on: 2022-10-03, 23:01:53 »

 Hi,
 i wish we could scatter on "scattered objects", without converting the scatter  objects to mesh.

For example, for covering  large walls with ivy, i wish we could  just scatter the ivy branches, and set the scattered branches as scatter-on targets but again, currently the only way to do that is to convert those scattered branches to mesh and set them as scatter-on targets.

A better implementation would allow us to use the poly IDs as areas so that, we could scatter the trees, and if to add fruits/special leaves to those trees, set the scattered trees (while still as CScatter  widget) as scatter-on targets and  just target a specific poly ID so that the fruits or leaves would appear on just the leaves but the trunk or leaves.

15

[Max] Feature Requests / Re: Decal object receive ffd modfiers

« on: 2022-09-23, 13:11:34 »

Agree with the request - for me, decals would prove much more useful if support for other mapping/projection modes would be added.
My idea would be that UV coords could be defined in a UV modifier or Unwrap mod on the mapped object and the Decal would get a 'use existing mapping channel' option along with a map channel ID (similar to how the legacy Displacement modifier works where you can optionally use an already existing mapping channel).
Let's see if it's doable.

Those are nice suggestions, but as an initial upgrade, i am just content with a very simple FFFx2 modifier, i believe it it would be the simplest improvement if possible at all...