Worklog for Trixx
Worklog 1
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| This is 3 months old project and almost finished, but anyway, I will start worklog for it... I decided to start this project so I can easily add any particle effect to any game I create in the future. Although many features are not needed for my current game project, I decided to add every possible feature I can think off, so I'd not need to dig into the old code later just to add something that some new project may need. Anyway, I'm sure that Blitz community needs this kind of project too ! There are lot of particle libraries for Blitz, but this one will be something special... I hope :) Current functional features ( v 0.98b ) 1.- Very fast.. I don't think it can be any faster than this. Why ? First of all, it's single surface. Second, it uses best combination of ClearSurface/AddVertex and Vertexcoords methods ( they both have their strengths and weak points ). Third - it's UpdateParticles function is optimized to maximum, and most important, it uses several powerful methods of "particle culling" - i.e. particles that are part of the surface but not visible will not be rendered. There are several other reasons why I say "Very,very fast", but you should wait for the first demo effects so you can see it in action :) 2. Objects as emitters - In many particle systems only points can act as emitters. In CPS emitters can be : - point, line, box, area, ellipse, sphere, cone, cylinder... and they can be rotated along any axis ! - You can also define one part of these objects ! Let's say half sphere, quarter of ellipse and so on... Particles paths can be defined in standard custom way or IN or OUT from these virtual object emitters This was one of the main features that I wanted from some good particle system. 3. Additionally to objects as source for particles, you can define exact number of points on objects that will act as "emit points". By default, particles are created randomly on the surface of the object, but for example , if you choose line as emitter object, you can set Points on 5 and particles will be created only from those 5 points evenly positioned across the line. 4. 2D and 3D viewports - one more very important feature You can define rectangle, ellipse or any convex or concave polygon on screen that will act as area where particles will only be visible ( or not visible ) You can define any number of these viewports and they can act only on specific emitters. 3D viewports can be box and sphere and will act separately or in combination from 2D ones. They are defined in "real world" coordinates, unlike 2D ones which are defined with screen coordinates 5. Particle "culling" - although emitters are single surface, particles that are out of screen or out of defined viewports will not be rendered next frame... Let's say you have 1000 particles currently active, but only 600 of them are currently visible - including this option your FPS rate will increase significantly ! CPS can achieve this through various methods - CameraProject , Custom Camera Project ( much faster then built-in blitz CameraProject ), using LinePick when particles are behind some object in the world, and trough 2D or 3D viewports And particles that are not visible will still be "alive", they will just be removed from the surface until they became visible again. 6. Forces - without forces, particle system is very limited in it's real game usage, so I added them too: - Simple forces - they act simply with adding specific number to velocity every frame - Global Forces - they are defined globally ( like wind, gravity ) and they take into account acceleration and mass of particles - Other Forces - they are defined as cones with Min/Max force, Min/Max range, direction and position. They also take into account mass and acceleration of particles. Like viewports, forces can act also on specific emitters, they can be changed over time etc.. 7. Collisions - I'm working on this right now - currently you can define collision objects as triangle, ellipse, rectangle and sphere but I'll add more of them, I think :) Particles can bounce, stop, slide or die when collide with collision objects more on collisions when it's finished :) 8. "OverLife" parameters for all particles properties ! It means that you can define up to 10 points in particle's life so particles will reach given value at that point and will go toward next value in next defined point in life. For example, you can define that particles start with red color, then on 10% of life they became green, on 35% they became purple, on 50% they became yellow, on 60% they became red again and so on. Another example - you can set particle's alphaoverlife property, so particle starts visible/ then on 30% of life became nonvisible/ on 50% 1/4 visible etc... You can set overlife values for color, transparency, velocity, spin, rotation, size etc... You can additionally set "repeater" value - so you can repeat defined cycle n times over particles life ! 9. OverLife values can be set for emitters too. For example - new particles that are created will start red, then when emitter reach 10% of it's lifetime, new particles will start green and so on... this may be little confusing as you read, but once you see it in action, everything will be easy :) 10. You can start emitting particles all at once, at specific rate or you can let particle system to choose best rate to achieve lastemitted/firstdied state ! 11. It's dead easy to use - simple emitters can be start only with 3-4 commands, and very complex particle systems can be achieved with 8-10 commands. The only command in your main loop will be UpdateAllParticles(). Or if you want to update only specific emitter - UpdateParticles(EmitterID). This way "non-important" emitters ( or emitters that are far from camera ) can be updated every n-th frame. 12. You can Freeze and Unfreeze specific emitters - Example: let's say you defined a fountain. But fountain needs 2 seconds to "build itself". Now, when it's not visible, you can freeze the fountain ( and save all FPS that it gets ) and unfreeze it when it becomes visible again. Unlike FreezeEmitter, StopEmitter will stop emitting new particles for fountain ( or optionally kill all of it's live particles ) Other features are more "standard" ones : - particles can face camera ( you can have different camera for different emitter ) - circular movement for particles - particles can use specific frame of texture ( using texture U/V coordinates ) - particles can emit particles from other emitters during their life, or start specific emitters when they die... - Particles can be rendered FirstFirst or LastFirst - Particles can be "aligned to motion " - Set blend mode, alpha mode, Fulbright mode - Start, stop, position, rotate emitters - Copy defined emitters into new ones - Parameters for particles : RGB ( color ), alpha, velocity, gravity, spin, rotation, number... and their variation values To do: - little more optimizing - more collision options - more 3D viewport objects - more demo effects - manual ... Today, CPS library is 104kb in size and over 3300 lines of code... Planned release date - end of April 2004 |