Archive for October, 2013

Mega Screenshot Teaser

Posted in Development on October 31st, 2013 by Maikel – 5 Comments

OpenClonk finally has functional screenshots again for the whole map, thanks to JCeasar and Sven2! One can make these screenshots in game in the chat mode (Return) by typing:

/screenshot X

where X can be any real number and determines the zoom level at which the screenshot can be taken. It is advisable to keep X between 0.1 and 10. This new feature can very well be used to view full landscapes and here is a teaser for a new World yet to come.

A full screenshot for a new scenario "Spiral" which is yet to come.

A full screenshot for a new scenario “Spiral” which is yet to come.

However, a lot of new settlement scenarios can already be played in the snapshots, among them Gem Grabbers where you need to collect gems from a series of sky islands. But there is many more to be discovered, so be sure to check the snapshots or stay tuned for the next release!

Grab gems from sky islands.

Grab gems from sky islands.

A new particle system

Posted in Development on October 10th, 2013 by Zapper – 2 Comments

Over the last few weeks, I wrote a new particle system for OpenClonk. The main difference for the player is that it should be a lot faster *).
Developers now have a new, finer way of defining the behavior of particles which makes more aesthetical effects possible than what the old particle system could provide. I am excited about what interesting effects the scripters will think of.

image of particle effect

my test particles

The next part of the article is probably only interesting for scripters, since it explains some of the technical details 🙂

Most information from the old Particle.txt is not needed anymore. What remains is the Name and Facet (to define the particle graphics). The other properties of the particles’ behavior are defined directly in script using a proplist. Here is an example of such a proplist:

var particles =
 Size = PV_KeyFrames(0, 0, 0, 100, 1, 750, 1, 1000, 6),
 Alpha = PV_KeyFrames(0, 0, 255, 750, 255, 1000, 0),
 DampingX = 700, DampingY = 700,
 ForceY = PV_KeyFrames(0, 0, 0, 750, 0, 900, -10 * GetGravity()),
 R = 255,
 G = 255,
 B = PV_Linear(255, 0),
 Rotation = PV_Direction(),
 BlitMode = GFX_BLIT_Additive,
 Phase = PV_Step(1, 0, 2),
 Stretch = PV_Speed(2 * 1000, 1000),
 CollisionVertex = 750,
 OnCollision = PC_Bounce()
for (var i = 0; i < 500; ++i)
 var angle = Random(360);
 var speed = RandomX(5, 40);
 CreateParticleEx("Fire", 0, 0, Sin(angle, speed), -Cos(angle, speed), RandomX(5, 1 * 36), particles, nil);

As you might see in the example above, you can animate a lot of the particles’ properties now. For example the size, the color or even the new physics properties like damping or a constant force that is applied to your particles to simulate wind or gravity.
For more information you can have a look at the particle documentation or at the reference for CreateParticleEx.

The old particle system is currently still in place, but you are encouraged to use the new one.

picture of explosions

some of Matthi’s experimental explosions

*) The new particle system renders all of the particles of the same type with a single draw call to the GPU, which should speed up the drawing a lot. Additionally the particle physics are simulated in a thread parallel to the normal game logic (moving objects etc.), which might also yield a few extra FPS.