Set Adafruit Neopixels to individual brightness?

I need individual pixels to light up in order with different levels of brightness, and retain that brightness throughout the loop. Currently whatever brightness I set the strip to overwrites all previous brightness settings. How do I restrict brightness values to only one pixel and keep it that way?

void setEvent(uint16_t string, uint16_t dom, float color, float brightness) 
    for(uint16_t i = 1; i < strip.numPixels(); i++) 
        strip.setPixelColor( string * 30 + dom, Wheel((color - 4000)/50) );
        strip.setBrightness( brightness * 85.0 );;

The setPixelColor method takes several arguments so you can change the individual brightness and colour of a single LED. The first value is the LED number and the other 3 are the RGB values to be shown by the LED.

Here are some examples I found

strip.setPixelColor(i, (0, 63, 0));  //1/4 bright green
strip.setPixelColor(i, (255, 0, 0));  //full-bright red 
strip.setPixelColor(i, (0, 255, 255)); //full-bright cyan
strip.setPixelColor(i, (127, 127, 0)); //half-bright yellow
strip.setPixelColor(i, (255, 192, 255)); //orange
strip.setPixelColor(i, (63, 63, 63)); //1/4-bright white

I suggest that you do not need to use the setBrightness method at all.

Recently I used a 12 led Neopixel circle in a project. I wanted to be able to dim this and added a 1k pot to the project.

Since the RGB values can only be a maximum of 255, I restricted the RGB values to no more than 25. At the same time I mapped the reading of the pot to 1-10.

I then mulitplied the RGB values times the mapped pot value. This gives me a value of 1 - 250 for each color.

While not perfect, it does give me what I wanted.

For your project it seems like you will have to set one at a time, so get rid of the for loop.

For this project I'm going to be processing large reams of data continuously (displaying neutrino events in a detector simulator, namely) so the for-loop is pretty necessary. I'm also setting the color from a single argument (eg: a time value where earlier times represent redder colors), so if there is any potential method that doesn't require setting individual RGB settings...?

Have you looked into the FastLED library?
Makes this kind of stuff - pretty easy to do.