Add storm support for camera exposure controls #3464
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Adds exposure:time, exposure:iso, exposure:fNumber, exposure:responsivity attributes and repurposes exposure attribute to be interpreted as exposure compensation. Adds UsdGeomCamera::GetExposureScale() method which allows users to calculate the imaging ratio (i.e. given a certain luminance on the sensor, what is the photometric exposure output) from these attributes. Also adds a unit test to test the above.
- move factor of 100 in exposure equation to tie it to ISO - clarify that the exposure equation also takes into account the lens system - clarify how shutter:open/close, exposure:time, fStop and exposure:fNumber are related
the intent of hijacking the current GetExposure() on the HdCamera was to automatically and transparently upgrade existing delegates to the extended behaviour provided by the new exposure controls. However, there was a bug in the implementation: existing delegates will be expecting the result of GetExposure() to be logarithmic, i.e. they use the result by raising 2^exposure, whereas the result of UsdGeomCamera::GetExposureScale() is a simple scalar multiplier. So, to keep backwards compatibility we need to take the log2() of the exposure scale before handing it off to Hydra
…tion we're using relative to that
Usd geom camera exposure
# Conflicts: # pxr/usd/usdGeom/wrapTokens.cpp
...by making exposure hydra attribute map to exposure USD attribute, and exposureScale map to ComputeLinearExposureScale. This means that existing render delegates that already query exposure will not get the more advanced behavior "for free", and will need to be updated to query exposureScale instead, but should lessen future confusion and potential bugs.
|
Filed as internal issue #USD-10512 (This is an automated message. See here for more information.) |
|
/AzurePipelines run |
|
Azure Pipelines successfully started running 1 pipeline(s). |
...for both HdCameraTokens and HdCameraSchemaTokens
...to make it clear this value is a flat multiplier, not a log2 exponent
pmolodo
force-pushed
the
usdGeomCamera-exposure-storm
branch
from
adb7ebb to
1a69581
Compare
…amera-exposure-storm
tcauchois
reviewed
Jan 28, 2025
| @@ -14,6 +14,7 @@ | |||
| #include "pxr/imaging/hdx/boundingBoxTask.h" | |||
| #include "pxr/imaging/hdx/colorizeSelectionTask.h" | |||
| #include "pxr/imaging/hdx/colorCorrectionTask.h" | |||
| #include "pxr/imaging/hdx/linearExposureScaleTask.h" | |||
There was a problem hiding this comment.
Note: this doesn't seem to be part of this CL; can you add it?
| @@ -54,9 +54,6 @@ class HdxColorChannelTask : public HdxTask | |||
| // Returns true if the values were updated. False if unchanged. | |||
| bool _UpdateParameterBuffer(float screenSizeX, float screenSizeY); | |||
|
|
|||
| /// Apply the color channel filtering. | |||
| void _ApplyColorChannel(); | |||
There was a problem hiding this comment.
Can you revert the changes to colorChannelTask? They seem unrelated.
| @@ -2297,6 +2297,42 @@ class Camera "Camera" ( | |||
| However, it follows that if even one property is authored in the correct | |||
| scene units, then they all must be. | |||
|
|
|||
| \\section UsdGeom_CameraExposure Camera Exposure Model | |||
There was a problem hiding this comment.
It would be great to rebase this CL on top of dev; now that the exposure schema has landed, it would make the PR much smaller.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Description of Change(s)
This is a follow-up / add-on to the PR which adds camera exposure controls:
It adds
HdxExposureScaleTaskto allow visualization of the camera exposure controls in Storm.See here to just see the additional changes, vs #3085:
Checklist
[X] I have created this PR based on the dev branch
[X] I have followed the coding conventions
[ ] I have added unit tests that exercise this functionality (Reference:
testing guidelines)
[X] I have verified that all unit tests pass with the proposed changes
[X] I have submitted a signed Contributor License Agreement (Reference:
Contributor License Agreement instructions)