Material: Brightness is not saved in material files

[klepto2]

If you open up a material in the editor or try to save it manually via code. The Brightness is not saved. 

[Josh]

It's not supposed to be. Brightness is just a hack to make up for the fact that the Win32 color picker only allows colors in the range 0-1.

The color is converted to 0-1 color and brightness for display in the editor interface, but it's really stored as a Vec4.

[klepto2]

thats what i thought as well, but when you choose another brightness than 100, the colors are safed normalized and after reloading it, the editor shows again 100 instead of the original value.

[Josh]

It depends. If any color channel is less than or equal to 1.0, then the brightness will be reset to 1.0. If any color channel is greater than 1.0, then brightness is used to multiply the values.

[Josh]

I tested a little bit, and it was working as expected. Please let me know if you think there is any problem.

Here is the code I use for extracting the brightness value, for colors that have one channel value greater than 1.0:

Vec4 c = material->GetColor();
c.a = Clamp(c.a, 0.0f, 1.0f);
float brightness = 1.0f;
if ((c.x > 1.0f) or (c.y > 1.0f) or (c.z > 1.0f))
{
	for (int n = 0; n < 3; ++n)
	{
		brightness = Max(brightness, c[n]);
	}
	for (int n = 0; n < 3; ++n)
	{
		c[n] /= brightness;
	}
}

 

[klepto2]

Ok, i don't know why, but it works now. But i would suggest to add the same functionality to the emission color.

[Josh]

Is emission greater than 1.0 really something that will realistically be used?

[Dreikblack]

3 minutes ago, Josh said:

Is emission greater than 1.0 really something that will realistically be used?

Yes, it can be used with bloom effect (for something like lamps, pressed buttons etc.)

[klepto2]

On 10/12/2024 at 3:59 PM, Josh said:

Is emission greater than 1.0 really something that will realistically be used?

it is more realistically than the brightness > 1.0 of the diffuse channel. In addition to what Dreikblack said, you can use the emission for much more: glowing signs, monitors with text on it and much more. Another benefit of having a brightness value (adjustable from the MaterialClass) is an easy way to implement flickering materials or ways to turn glow on/off.

On 10/11/2024 at 8:07 PM, Josh said:

I tested a little bit, and it was working as expected. Please let me know if you think there is any problem.

Here is the code I use for extracting the brightness value, for colors that have one channel value greater than 1.0:

Vec4 c = material->GetColor();
c.a = Clamp(c.a, 0.0f, 1.0f);
float brightness = 1.0f;
if ((c.x > 1.0f) or (c.y > 1.0f) or (c.z > 1.0f))
{
	for (int n = 0; n < 3; ++n)
	{
		brightness = Max(brightness, c[n]);
	}
	for (int n = 0; n < 3; ++n)
	{
		c[n] /= brightness;
	}
}

 

This looks right, but it has a major downside (at least in my opinion): Once you set the brightness to 0.0 you lose the color information. In my opinion you should always store the color and brightness independently in the material file. How it is then used in the engine doesn't matter, but it will prevent users from accidentally delete the color information.  

[Josh]

Okay I will do it.