Assignment 2 The Game Development Pipeline Solution

Assignment




You will work on handling multiple entities of two di erent types and implement tab selec-tion. For now, our physics remains the same. Please use the posted solution to assignment one as the basis for this assignment.




0.1 Multiple entities and selection (30)




First, make a large (10000 10000) planar textured surface located at the origin on the xz plane at a height speci ed by a surfaceHeight variable (10 points). Experiment with the di erent ways of texturing your ground plane with water. You may use the previous assignment's posted solution for pointers.




Create and load ve (5) cubes and ve (5) spheres in two rows of ve into your evolving game engine. Bind the tab key to selection - that is - pressing the tab key will round-robin select the "next" entity. A selected entity, and only the selected entity, has a visible axis aligned bounding box (20 points for selection).




We need to distinguish between Ogre's Entity class and our Entity as used in the para-graph above. To be clear I will use Entity381 when I do NOT mean to refer to Ogre's entity class. So, to make this clear, I reproduce the above paragraph with Entity381 replac-ing Entity.




Create and load ve (5) cubes and ve (5) spheres in two rows of ve 381Entities into your evolving game engine. Bind the tab key to selection - that is - pressing the tab key will round-robin select the "next" Entity381. A selected Entity381, and only the selected Entity381, has a visible axis aligned bounding box (20 points for selection).




0.2 Simple Physics (15)




The arrow keys (or the numpad keys) on your keyboard control the selected Entity381's velocity. Make the selected Entity381 move in 3D with a velocity determined by the numeric




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pad's arrow keys and PGUP/PGDOWN. Key presses increase or decrease the x, y, and z components of the Entity381's velocity.




0.3 Camera control (5)




You will continue to control the camera with the WASD and E and F keys. In addition, you will now also use, the LeftShift+A and LeftShift+D keys to control camera yaw.




0.4 Quitting (0)




Hitting the q key should gracefully shut down your running game engine.




0.5 Engine Architecture and Design (50)




Here are architecture and design elements that you MUST follow. I assume that your createScene function is in as2.cpp










(10 points) Create a Entity381 class to hold each Entity381's position, velocity, Ogre::SceneNode pointer, mesh le name, and other information. More information about 381Entities follows, for now, note that 381Entities will be managed by an Entity Manager.




(10 points) You will create one instance of an EntityMgr class in createScene. The EntityMgr manages entities. This means the EntityMgr




maintains a list (or map or array) of all entities in your game engine



tracks which entity is currently selected



creates entities and assigns them a unique identi er. This means you will need a Entity381* CreateEntityOfTypeAtPosition(EntityType type, Ogre::Vector3 pos) method. I specify Entity381 below.



has a void Tick(float dt) method. This method iterates through the list of Entity381s and calls each Entity381's Tick method.



(10 points) Create and use an Entity381 class to hold information about your entities. Entity381 members must include




entityId, entityName



position, velocity



ogreSceneNode, ogreEntity (pointers to the entity's Ogre::SceneNode and Ogre::Entity)



a list of Aspects. We will specify Aspects below.



Apart from the constructor, Entity381 will also declare and de ne a void Tick(float dt) method. This method will iterate through the list of this Entity381's Aspects and call each Aspect's Tick method. For this assignment you will create the two aspects listed and described below.






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other members as needed



(5 points) Each of the two Entity381 types (Sphere and Cube) should be implemented as a separate subclass of Entity381.




(15 points) Create and use an Aspect class and three subclasses of Aspect. The Aspect class is simply a base class to hold




{ a pointer to this aspect's Entity381




{ a virtual void Tick(float dt) method that will be overridden by subclasses.




Each entity will have three aspects one of each subclass type below.




Physics (5 points) - This aspect will will simply update the Entity381's position inside Tick(pos = pos + vel * dt).



Renderable (5 points) - Renderable manages the scene node (or nodes) and Ogre::Entity associated with our Entity381s and on every tick, copies the position from our Entity381 to the Entity381's scene node. The equivalent of cubeSceneNode-setPosition(position); from my solution to assignment one.



Rotator (5 poitns) - Rotator slowly rotates each entity. You will be changing the 381Entity's SceneNode's yaw by a small amount every tick



Please use Ogre's vector classes for vector math.




In your frameRenderingQueued method you will call, your EntityMgr's Tick method. This will go through the list of Entity381s and call each entity381's Tick method. Each Entity381's Tick method will then iterate through that Entity381's two Aspects and call each Aspect's Tick method.




These constraints will result in a cleaner, better, design for your emerging game engine.




They will also increase your understanding of inheritance and game engine architecture.




Extra Credit




This is cumulative!




Add mouse selection (+5)




Add islands in your waterworld (+3)




Find and use new 3D models. Not the ones found on the ogre wiki: http://wiki. ogre3d.org/Ogre+Models. Hand in a document that provides a step by step tutorial on how to incorporate each of your models in the game engine.




Add group mouse selection (+10)




Add the ability to use standard RTS game mouse commands in order to have a selected (left-clicked) ship or boat to intercept another (right clicked) ship (+10)




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Turning in your assignment




Assume that this format will be used for all your laboratory assignments throughout the semester unless otherwise speci ed.




Demonstrate your working program in the lab on the due date.



In lab, submit your code using Canvas.



Make a directory (folder) named as2.



Make a movie demoing your assignment and place this in as2



Place all your project les in as2 (you will demo from this folder in lab).



Tar and gzip or Zip the entire folder and submit using Canvas. If you do not submit this le, you will lose 20% points.



Ask me (sushil@cse.unr.edu) if you have questions.







Objectives




Demonstrate an ability to apply knowledge of computing, mathematics, science, and engineering by learning and applying knowledge of Python to solve a problem (1)



Demonstrate an ability to analyze a problem, and identify, formulate and use the appropriate computing and engineering requirements for obtaining its solution (5)



Demonstrate an ability to use the techniques, skills, and modern engineering tools necessary for engineering practice (11)



Demonstrate an ability to apply design and development principles in the construction of software systems or computer systems of varying complexity (13)




























































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