GDE Lab 1 – Traffic Light Pg. 1 Lab 1 Traffic L.docx
- 1. GDE: Lab 1 – Traffic Light Pg. 1 Lab 1: Traffic Light Setup Start a new project. Save the scene. Review the submission steps at the bottom to ensure you save the scene name correctly. Additional References tools to help newcomers become better familiarized with the tool suite. I cannot recommend this enough. fantastic. If you want to know anything about a particular component or function or class, they have it documented and easily accessible. It won't give you all the answers, but without this, developing for Unity would become much, much more difficult. Preparation Make sure you complete Experiment 1 and 2 before attempting this lab.
- 2. Goal The goal for this lab is to implement a simple traffic light that has a state machine driving its behavior. By the end, you should have a visual representation of a traffic light with three spheres that represent the three lights. Using time to determine when to transition, switch the lights from green, to yellow, to red and then back to green. Additionally, input can be used to change the traffic light's behavior. http://unity3d.com/learn http://docs.unity3d.com/ScriptReference/ GDE: Lab 1 – Traffic Light Pg. 2 Instructions Let's create the actual traffic light together. Here is the step-by- step construction process: Create a Cube object Rename the Cube object in the Hierarchy to TrafficLight Create three Spheres. Rename them to Green Light, Yellow Light, and Red Light. Make the Traffic Light
- 3. object the parent of all of the Light objects by dragging all three spheres in the Hierarchy on top of the TrafficLight object GDE: Lab 1 – Traffic Light Pg. 3 Once all three spheres are children of the Traffic Light object, the only other thing left to add to the scene is just a little bit of light. Add a directional light to the scene. The position of a directional light does not matter. You can move it out of the way. If the light is too bright, you can lower the intensity in the inspector. The scene should now roughly look like this. In scale mode, shape the cube until it looks like a traffic light. Move the three light spheres such that they protrude through one side of the traffic light object. You'll notice that the spheres have taken on the scale of the parent. It's important to remember that translation, rotation and scale actions performed on the parent affect the
- 4. children in the same way. Use the scale tool to make the spheres look like a light again and position them accordingly GDE: Lab 1 – Traffic Light Pg. 4 Once all three lights are in place, move the Main Camera object so that the Traffic Light object is in the frame and you can see the light spheres Scripting Now you are ready to begin the programming portion of this lab! Select the Traffic Light object and add a new script component. Add two script components, one named TrafficLight and one named TrafficLightStateMachine. Open each file in MonoDevelop. Traffic Light This class is going to be the data model for a traffic light. That is to say, that it is going to be a representation of
- 5. what a traffic light is (attributes, such as strength, health, jump height, etc) but will include no information about what a traffic light does (behaviors, such as walk, run, jump, shoot, death). Implement the following requirements: 1. 3 private member variables, one for each light color, that indicates how much long that light should remain before transitioning to the next light. 2. All 3 variables should be marked with the serializable tag to expose each variable to the inspector. 3. 1 private member variable to track how much time has passed since the light last changed. Do not expose this variable to the inspector (private member variables are not exposed automatically). 4. Implement an accessor/get function for each member variable. a. For example, int GetHealth() { return myHealth; } 5. Add a ResetTimeSinceLastTransition() function that will reset the variable you created in step 3 to zero. Call this function in the Start() function of the TrafficLight object. 6. In the Update() function, update the variable created in step 3 to keep track of time elapsed.
- 6. 7. In the Start() function, change the material's color to gray GDE: Lab 1 – Traffic Light Pg. 5 This is the method you will use to change the color of each light sphere to different colors. Gray will act as the default color. Check the scripting reference for the Color object to see the other colors available. Remember that each light is its own object that is a child of the TrafficLight object in the hierarchy. You will need to access the renderer of each child in order to change the material color of that particular light. Use GameObject.Find() and pass in the name of the light object you want to modify. TrafficLightStateMachine This class is responsible for driving the behavior of the object at run-time depending on information stored in the data model. As such, the requirements for you are going to be to implement a behavior. How you choose to implement a behavior is up to you. However, I will be grading your solution not just on the functional requirements, but on code organization and architecture.
- 7. I know you're chompin' at the bit to get started but there's something I haven't shown you yet. We went through all that trouble to create the TrafficLight data model for a reason. State Machines typically have a reference to the data model that they are managing. Add a private variable of type TrafficLight and name it target. In Start(), use the GetComponent function to initialize target. With target, you have access to the accessors you created in the TrafficLight object which will help you as you implement each state. Implement the following behaviors: the time to stay red, transition to green. than the time to stay yellow, transition to red. than the time to stay green, transition to yellow. Blinking Yellow: Make the light blink at specific intervals by changing the color between gray and yellow. o Only blink yellow if the user presses the space key while the
- 8. light is green. o Stop blinking yellow if the user presses the space key. Transition to red. GDE: Lab 1 – Traffic Light Pg. 6 Rubric Lab Requirements 100 100 Setup New scene: Lab1_TrafficLight_LastNameFirstName 5 5 Traffic Light added to the scene 10 10 TrafficLight.cs All member variables are private 5 5 3 variables to track how long to stay in each light (r,y,g) 5 5 R,Y,G timer variables marked as serializable 5 5 Variable to track time since last transition, incremented in Update() 5 5 Accessor/Get functions for all member variables 5 5
- 9. TrafficLightStateMachine.cs TrafficStates enum 5 5 Dictionary member variable declaration 8 8 Green state function 8 8 Red state function 8 8 Yellow state function 8 8 Color materials applied to lights 8 8 Loose Ends Traffic Light prefab 5 5 Add a blinking yellow light state 10 10 Common Lab Requirements These requirements are the same in every lab. Make sure you are familiar with them. 1. (-5 points) Missing all or part of the script file comment header (Author, Date, Credit, Purpose) 2. (-5 Points) Submission files not named correctly (LastName_FirstName_Lab#). 3. (-5 Points) Submission not in correct file format (.zip). 4. (-100 Points) The submission cannot be opened or is otherwise not reviewable.
- 10. 5. (-5 Points) Submission includes Unity’s standard assets. 6. (-5 Points) The code formatting is chaotic or inconsistent. 7. (-1 Point) The scripts contain syntax warning(s); point deducted per unique warning. 8. (-10 Points) The scripts contain syntax error(s); flat point deduction. GDE: Lab 1 – Traffic Light Pg. 7 Submission When you have completed: 1. Make sure the root asset folder and scene file are named LastName_FirstName_Lab1 2. Export your assets as a Unity package. a. Name the file LastName_FirstName_Lab1. b. The package should include the scene, materials, textures, meshes, audio clips, prefabs, scripts and physics materials. c. Do NOT include any of the Standard Unity assets. 3. Place the files (Unity Package) in a zip file. a. If the submission is missing, no features will be evaluated
- 11. and a zero (0) grade will be achieved. b. Do not include any other files or folders. Test the package in a new (different path) empty Unity project. Also, test the zip file on another computer before submitting it. This way you can ensure that you have the correct lab, and that it works as expected. Once you’re ready, submit the zip on FSO. After it’s uploaded, you are done! Tips A feature has you stumped? Here are some helpful suggestions: 1. Take a short break to stretch your legs or clear your eyes; but, never give up! 2. Review, and even use, your assets and scripts from the Experiment project. 3. If you have a compiler error, try using its complete or partial description in a Google search. Syntax issues are usually caused by: a. Misspelling a variable or function name. b. Missing a, or adding an extra, parenthesis, bracket, or semicolon. 4. Compare the line that has the error with similar lines of code that you know work. a. Sometimes the offending code is one or two lines above from where the error is reported.
- 12. 5. See http://docs.unity3d.com/Documentation/ScriptReference/index.h tml for references on how to use the fundamentals of programming and Unity specific components. 6. If you still can’t figure it out, send the instructor an email or contact them on Skype. 7. If you're unsure how to proceed with the implementation of a feature, The Game Mechanic Explorer is a fantastic resource to see example implementation methods. The implementations are all in HTML5, but the problem solving is very similar. The language and syntax are different but you should take some time to poke around and play around. These do not implement state machines http://docs.unity3d.com/Documentation/ScriptReference/index.h tml http://gamemechanicexplorer.com/ GDE: Lab 1 – Traffic Light Pg. 8 Example Here’s what the scene should look like in the end when running: