This scene uses legacy (pre-v4) medium/refraction resolving that is not based on geometry normals and produces incorrect results when multiple medium containers are intersecting. The scene was loaded with the legacy behavior to make the rendered result more consistent with older versions of Corona, but we strongly recommend switching to new behavior using the button below. If normals orientation is correct, switching will preserve or improve the look of the scene.
This message appears when using Corona 4 or newer and when a scene created with Corona 3 or older is opened.
Ignoring or closing this message will result in using the legacy medium/refraction resolving, which means that:
- The renders will be more consistent with older versions of Corona. This is useful if you are re-rendering a scene, which was originally rendered with Corona 3 or older. Please however note that we cannot guarantee that the results will be identical, because some differences between Corona 3 and Corona 4 results may appear, even when the legacy resolving is used.
- More effects may render incorrectly or with artifacts, especially in case two or more objects with volumetric effects or refractive materials are overlapping.
Clicking on the "Switch to new medium resolving" option will update the scene to the new Corona 4 medium/refraction resolving, which means that overlapping objects with volumetric effects or refractive materials will render better (correctly), but they will look different than in older versions of Corona.
Note #1: The medium resolving method can be changed even if the notification was closed or accepted. To do it, go to Development / Experimental Stuff rollout, and toggle the "Use legacy medium resolving" checkbox under Basic configuration.
Note #2: This message will appear every time an older scene is opened, until it is resaved with Corona 4 or newer. If you are repeatedly getting this message when opening an older scene, then resaving this scene is the only solution to get rid of it. Please do however note that scenes saved with Corona 4 cannot be opened in Corona 3 or older.
Examples
Two intersecting spheres. Two separate objects (left) and one combined object (right):
Corona 3:
Corona 4, legacy medium/refraction resolving mode enabled:
Corona 4, new medium/refraction resolving mode enabled:
Overlapping volumetric objects. Two separate objects (top) and one combined object (bottom):
Corona 3:
Corona 4, legacy medium/refraction resolving mode enabled:
Corona 4, new medium/refraction resolving mode enabled:
Corona Volume Grid object inside volumetric fog:
Corona 3:
Corona 4, legacy medium/refraction resolving mode enabled:
Corona 4, new medium/refraction resolving mode enabled:
Corona 3:
Corona 4, legacy medium/refraction resolving mode enabled:
Corona 4, new medium/refraction resolving mode enabled:
Note: in this example, we rendered exactly the same scene as above. The result is incorrect, because in older versions of Corona, direction of normals did not matter. In Corona 4 and newer, normal direction is considered. This means that in the below example, the direction of normals of the liquid mesh is incorrect. Flipping normals of the liquid mesh solves the issue instantly.
See this guide for more info: How to model liquid in glass?
