Im sorry in advance if this is a stupid question but I just cant seem to find the answer.
I am working on a project in Ogre and what I need is to create a Particle System but instead of using the examples provided by OgreOde, I want one of my own. The difference is I want to create a Praticle System with just one particle and apply a texture to that particle with an image that I already have on my laptop.
Is there a tutorial/example/someone that can help me on this one??
Thanks.
In general
The "Particle Script" section in the Ogre manual would be a good place to start: http://www.ogre3d.org/docs/manual/manual_34.html#Particle-Scripts
Another source of inspiration is the particles section in our wiki: http://www.ogre3d.org/tikiwiki/Particles
Regarding your concrete problem
You just need a very basic particle script with:
quota set to '1' since you only always want one particle
a simple material script referring your image/texture
an emitter that will spawn the particle, with some settings regarding how long that particle should live and the delay when a new one should be spawned
However: I cannot really image a use case for a single particle, since all you will get is just a single billboard, so why not use a billboard in the first place?
Related
Context
I'm a beginner in 3D graphics and I'm starting out with Vulkan, which I already know it's not recommended save it please, currently working on a university project to develop the base of a 3D computer graphics engine based on the Vulkan API.
The problem
Example of running the app to render the classic 2D triangle
Drawing a 3D mesh after having drawn the triangle
So as you can see in the images above I want to be able to:
Run the engine.
Choose an object to be drawn.
Close the window.
Choose another object to be drawn.
Open the same window back up with only the last object chosen visible.
And the way I have been doing this is by essentially cleaning up the whole swap chain and recreating it from scratch once the window is closed and a new object has been chosen. Now I'm aware this probably sounds like terrorism for any computer graphics engineer but the reason I'm doing this is because I don't know a better way, I have just finished the vulkan tutorial.
Solutions tried
I have checked that I do a vkDestroyBuffer and vkFreeMemory on the current vertex buffer before recreating it again once I choose a different object.
I have disabled depth testing entirely in case it had something to do with it, it doesn't.
Note: The code is extensive and I really don't have a clue of which part of it could be relevant to the problem, so I opted for not cluttering the question, if there is an specific part you think it might help you find the solution please request it.
Thank you for taking the time to read my question.
A comment by user369070 ended up drawing my attention to the function I use to read OBJ files which made me realize that this function wasn't cleaning a data structure I use to store the vertices of the object chosen to be drawn before passing them to the vertex buffer.
I just had to add vertices = {}; at the top of the function to solve it.
I want to develop a drone using Webots with python or c++. I want to program the drone to take off automatically, follow a predetermined route (like moving on a sinusoidal pattern) and then return and land. Does anyone have an experience in doing this or know of any documents helpful to this that can be shared with me, please?
By the way, I have started my coding, I want to set 2 propellers to rotate clockwise and the other 2 to rotate in the opposite direction when making it to take off so I have tried to set the velocity for 2 propellers with a negative value as the code is shown in the picture attached but those 2 propellers start later than the other 2 so it affects the drone's performance. Does anyone know what the problem is?
Thank you so much!
About your propeller issue, it is probably simpler just to inverse the axis of two of the propellers.
You should probably have a look at the example of drone simulation already available in Webots:
https://www.youtube.com/watch?v=-hJssj_Vcw8
You can find the documentation of this drone model at:
https://www.cyberbotics.com/doc/guide/mavic-2-pro
Here is the source of the model: https://github.com/cyberbotics/webots/blob/master/projects/robots/dji/mavic/protos/Mavic2Pro.proto
And the source of the controller:
https://github.com/cyberbotics/webots/blob/master/projects/robots/dji/mavic/controllers/mavic2pro/mavic2pro.c
I've create a ParticleSystem in Ogre so that my object emitt, suppose, a lot of star.
My question is: how can I realize the interaction of this stars with the environment and the objects in the scene too? but more importantly, can I do this issue with ParticleSystem?
Any help will be appreciated!
update
I'm trying to use inside my particle file:
affector DeflectorPlane {
....
}
A DeflectorPlane supports as the name suggests only a single plane of which particles can bounce of (see entry in Ogre manual).
Having particles bounce of arbitrary surfaces involves a lot of heavy collision detection and is therefore a task that is not in the responsibility of a rending but a physics engine, hence Ogre3D has no out-of-the-box support for this requirement.
But there are four different options in terms of already existing Ogre3D physics engine wrappers: Newton, Bullet, PhysX and ODE. Each of the wrappers has its own dedicated section in the Ogre Addons forum with further information and links.
I am able to implement particle system in cocos2d and now i want to attach my particle with a dynamic b2Body, so that, it can follow the body.
I have found a tutorial about Cocos2D Particles Following b2Body at [this site]. But not understand "how to use" section. Can any one please tell me, how can i attach my particle with my b2Body?
Firstly, you should create an object that contain the b2body.
Secondly, you should connect the object to the b2body.
If you don't know how to do this, you can read this question
Lastly, you should just add the particle system as the child of the object.
I am developing a 3d facial animation application in java using opengl(jogl) i had done the animation with morph targets and now i am trying to do a parametrized facial animation .
I can't attach the vertex of the face with the appropriate parameter,for example i have the parameter eyebrow length ,how could i know wish are the vertex of the eyebrows (face features),please please could anybody help me i'm using obj file to read the face model and face gen to create it.
I appreciate your help .
For each morph target you assign each vertex a weight, how strong it is influenced by the respective morph target. There's no algorithmic way to do this, this must be done manually.
Lightwave OBJ file format may not be ideal for storing the geometry in this case, since it lacks support for storing such auxiliary data. You may extend the file format, however this will probably clash with programs expecting a "normal" OBJ.
I strongly suggest using a format that has been designed to support any number of additional attributes. You may want to look at OpenCTM.