Design Patterns Summer Course 2010-2011 - Session#2
- 1. Day in Programmer`s LifeSession #6MuhamadHesham
- 3. Day in Programmer Life
- 4. GOF visit
- 5. Project DescriptionPattern’s ChallengeAre they Twin patterns?What are the differences between State and Strategy Pattern?
- 6. Our Target GameLearning through Game ProgrammingWhy Game Programming ?1.Fun& Interesting2.Resourceintensive software3.Interactions till death4.Coding non-stopOOD & Design patterns in action
- 7. Our Target GamePlatformer SkeletonMain Actors Level
- 8. Player
- 9. Enemy
- 10. GemCall for new requirementOnce the player collects a gem I want:Enemy increases its speed.Other gems change its color to a random color.
- 11. First try for implementation1. We need find the place in code where the gem is tested for being collected.2. We need modify enemy speed.3. We need modify gem color.
- 12. 1. We expose private members to the public.2. We are dependant on certain members.3. Each time we need modifythe level code.Without correct patternOur code smells bad!
- 13. Call for new requirementOnce the player die I want:Enemies speed is reset.Other gems change its color to black.
- 14. Call for new requirementEach level can be in one of two styles:PharonicAztecFirst level is Aztec.Second and third levels are Pharonic.
- 15. First try for implementation1. We need find where we decide which image we load.2. Categorize images to 2 sets, Pharonic an Aztec.
- 16. Each time we add a new theme we add piles of if-elsestatements.Our class do more than its job (SCSR).Without correct patternOur code smells bad!
- 17. Call for new requirementMy nephew has another opinionFirst level is Pharonic.Second level is AztecThird levelis random.
- 18. Call for new requirementI want the enemy turn crazy when you collect a gem.If you touch the enemy while it is crazy, you die and it turns idle again.Increase crazy enemy speed by 4 times.
- 19. First try for implementationWhat do you think we need do this time ?
- 20. Violates Open Closed Principle.Further additions will cause bugs.State transitions are buried between if-else.Without correct patternOur code smells bad!
- 21. Original Enemy State Machinereach cliffafter a whileRunningIdle
- 22. Updated Enemy State Machinereach cliffafter a whileRunningIdlegem collectedgem collectedplayer diedCrazy
- 23. Call for new requirementI want …Go to HELL !!!
- 25. GOF Visit: OrganizationLet`s ask the authors
- 26. It is Project Time!