Visualization HDR in Unity

With conventional 3D visualization, the components of a pixel of different colors are represented by a fractional number from 0 to 1. The larger it is, the greater the intensity of the component on the screen. It’s easy to use, but the result is different from what we see in real life with our own eyes.

The fact is that in a healthy person they adapt to lighting conditions. Because of this, an object that seems white in a room with poor lighting can actually be less bright than another object that seems gray in the daylight. An additional factor of the unrealistic nature of this result is that the human eye is more sensitive to differences in the brightness of objects in the lower range than in the upper one.


To make 3D visualization of architectural objects more convincing, the rendering should be adapted in such a way that the ranges of pixel values ​​more accurately reflect the level of light, bringing the scene as close as possible to how it would look in reality. These values ​​will need to be re-linked to the range that is available on the Unity display, but the result will be more realistic.

The meaning of HDR rendering lies in the possibility of internal image processing using values ​​that are not in the range from 0 to 1.

HOW TO USE Visualization HDR in Unity?

For each HDR camera, you need to include it separately in its properties. When it is started, the scene will be generated in an image buffer capable of applying values ​​outside the range specified above. After that, the final processing of various effects, as well as conversion to the standard LDR, so that the result could be displayed on the display.

Advantages of Visualization HDR in Unity:

Even in areas with a high level of intensity, the colors will not be lost;

In zones with low-frequency lighting, there will be less banding artifacts;

The effects of bloom and glow will look more realistic.

Disadvantages of Visualization HDR in Unity:

Some equipment does not support HDR;

Because of the use of floating point buffers, the drawing process will require more time and memory.

ABOUT EFFECTS of Visualization HDR in Unity

Tone mapping, which is responsible for converting HDR values ​​to LDR for display on the screen, can be implemented in different ways. Suitable for one case may be completely inapplicable to another. In Unity, you can find different methods, each of which deserves attention.

The adaptive nature of the tone mapping effect allows you to simulate the eye, camera, etc., which are watching the scene. For this, it is applied gradually, i.e. first the scene will be very bright and without the use of tonal compression, and only then the picture will become more real.

The use of HDR in interactive architectural visualization gives more possibilities for post-processing. The bloom effect in Unity can only be used in zones with intensity greater than 1, because otherwise, it may damage the image. If you apply it in the specified zones, the result will always be excellent.