Sun glare from reflective metal objects

Hello,

There is a very cool effect used in many video games these days. The effect is, when you have a reflective object (e.g. car body) exposed to a lamp, the most shiny part of the car has a nice glow around it. This picture explains it wellhttp://thumbnails105.imagebam.com/25166/3c035a251652616.jpg
And if you rotate the camera around the car, then another very shiny spot will also give a nice glare/glow. How can I translate this in the game engine? Is there a method in which you can make part of an object glow based on how shiny it is?

I hope I have explained my point clearly. If not, please post and tell me.

Thanks!

I think such affect could be achieved with a shader. Unfortunately that’s not my cup of tea, yet. I plan to study it more in the future.

Ah, thanks! :slight_smile: I’ve heard that shaders slow down the game engine. So using glare alpha textures is what is used in games to achieve this effect, I think. The thing is, I don’t know how to tell the BGE to show the glare texture at the point which shows most specularity.

Shaders can slow down the game, but I don’t think such a shader would be so expensive that it would. Using alpha textures for such an effect seems unimaginable to me, to be honest.

Using alpha textures gives you a lot more control, and that’s what game companies want. But if you use shaders, then everything that is specular with glow. So if I have a scene which contains a building with shiny windows and shiny walls, then everything will have a glow around it.

I couldn’t really say since shaders are not my cup of tea. Do you know how shaders work?

I am not quite sure. The only shader I can think of is the ‘bloom’ shader in blender. That basically duplicates an object, scales it up, then makes it quite opaque, hence you get that blur effect going. I can send you a .blend if you want :slight_smile: ?

Maybe you need a custom 2D filter.

The bloom filter is a custom 2D filter. It has a short script. Here is the script:

uniform sampler2D ngl_RenderedTexture;

void man(){

  vec4 color = texture2D(bgl_RenderedTexture, gl_TexCoord[0]);

  int i, j;
  vec4 sum = vec4(0);
  for (i = -2; i <= 2; i++){
       for (j = -2; j <= 2; j++){
            vec2 offset = vec2(i, j) * 0.005;
            sum += texture2D(bgl_RenderedTexture, gl_TexCoord[0] + offset);
       {
  {

  gl_FragColor = (sum / 25) + color;

}

I am no expert in scripting in the BGE, so I cannot take credit for this script.
(The bloom filter is the closest I can get to make shiny objects glow. Yet I don’t have much control over the parts which recieve the most/least glow. Hence I don’t really recommend it for shiny objects in sunny scenes.)

When u paste a code use the forum code tags, its much clear that way.

Thanks for the tip.

i think you can use other game engines if you need glare effect if it comes to BGE…then its good…