WingNuts and Bolts

# Particles

This section details the particle system

WingNuts has a very complex particle system that can easily make some complex effects. Particles represent everything from explosions, to smoke, to little stars when you collect a goody.

Your standard particles window.

First you need to make a new Particle with the New button

Then you need to choose an image for your particle. Simple is always better. As pictured in the image above, my standard explosion poof is just a small image.

The cluster option.

The Cluster option is only for viewing in editor explosions. It will not affect your particle, except how you view it in editor. This also applies for the rate. The real reate particles are created lie in another section, this lets you set a test rate. Usuall 100/sec is fine.

To view a particle click the mouse in the window. You will notice the particle follows your mouse. If you click an hold you will see the particle generated for a long time. Lets get into the specifics.

Animation frames - this is how you want your particle to animate. This only applies if you have an animating image.

Spin particle between _____ and ______ degrees/sec. This lets you spin the particle around. The first value is the minimum degrees it will spin, and the 2nd number is the max. Two very different values will create a big difference between speeds. Two simliar values will make the particles spin closer to the same rate.

Random spin direction - this will randomly pick a direction to spin for each particles. This can help make an effect feel more "random" and organic rather than the same each time.

Inital velocity - This is how far the particle will move from it's origon.

Final velocity - This is the velocity the particle will be moving at the end of its cycle. If you make this value large and the initial velocity small, you can have a particle that seems to "burst" at the end.

Life time - This is how long the particle will exist. If life time does not match the animation life time, then the animation will either loop or slow down to match.

Emission distance - This is how far from the center the particle will be created. This can create a ring effect.

Emission angle - This is the angle that the particle is created. Setting this to 0 to 360 ensures the particle spawns in all possible angles. Narrowing this field will create a cone.

Initial Time delay - This is how long before the particle is spawned. You can use this to delay effects to chain things like explosions or shockwaves.

Inherit emitter velocity - Many particles come from emitters (such as a jet shooiting a bullet). If your emitter is moving you may want your particle to move with it. You can also set the percentage of the velocity to use (such as maybe only 50% so it falls behind the jet).

Emission angle is velocity-relative - this means the angle the particle comes out is relative to the direction it's moving. Or you can have random.

Apply air drag to particle - This creats a drag effect of the particle slowing down.

Enable wind turbulator - These conditions affect the particle as if it's in the wind. For a short particle such as a explosion or a muzzle flash this may not be very noticeable. But if you have a longer effect, such as continually such as a long ammount of smoke, you may want it to sway with the wind.

Use additive blend drawing mode and not normal copy - this is a very powerful effect. It uses an additive OpenGL effect to draw your graphic. For instance:

This is a normal particle

This is an additive particle

As you can see, when the particles draw over each other, they blend the image and it becomes more intense. If you have enough images on each other the effect is a very bright point of light. For something like an explosion this effect can be very stunning.

You can also adjust the color of the particle by removing colors. Just like the textures in the Map section you can make a particle become a new color with these options. By removing color you can shift the color of a particle. 255 is the highest value and means all of the color is represented. So if you want to make a particle Red, you should drop the Green and Blue values to zero. The Alpha value is how transparent your particle is. 255 is no transparency and 0 is fully transparent (or invisible). You can set an initial color and a final color and it will fade between the two. You can also set a minimum and maximum color to fade to for both Inital and Final colors. This means the program will pick a random value between the 2 values you have provided. This allows the particle to appear more random.

Use alternate color randomization scheme - to use your new colors you just set up you will need to check this option, then choose what kind of equation the game uses to determine how fast it changes colors:

- None (no change) - This option will not change the color

- Linear (gradual) - This opion will change the color along a constant time. The fading will be even it will spend the same ammount of time in each color.

- Quadratic (quicker at end) - This option will make the change happen faster toward the end of the particles life time.

- Cubic (very quick at end) - This option will make the change happen very fast at the end. This will result in the particle spending most of it's life time as the inital color then a very fast change to the final color.

- Quadratic (quicker at beginning) - This option will make the change happen faster toward the beginnign of the particle's life time.

- Cubic (very quick at beginning) - This option will make teh change happen very close to the beginning. This will result in the particle spending most of it's life as the Final color.

Particle fading rate - This is how fast the particle fades from existance. None will have it just vanish abruptly (this can be advantagous in some situations). Or you can use the fading options. These options match that of the color options.

Particle size change - This is how large or small you want the particle to become. 100% is actual size. You can have the particle shrink to nothing, or grow to very large. Again you can use the same scaling methods used in color change and fading rate.