The first step is to upload the Helicopter images from a strip. 1) Click on Resources > Create Sprite 2) Name it spr_helicopter 3) Click Edit Sprite

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1 GAME:IT Helicopter Objectives: Review skills in making directional sprites Create objects that shoot and destroy for points Create random enemies on the scene as game challenges Create random enemies on the scene as game challenges

2 The first step is to upload the Helicopter images from a strip. 1) Click on Resources > Create Sprite 2) Name it spr_helicopter 3) Click Edit Sprite

3 4) Click File > Create from Strip and select the helicopter.png file

4 4) In the Loading a strip image pop-up box, enter the following: Number of images: 3 Images per row: 3 Image width: 64 Image height: 64 Click OK This creates the 3 sub-images that will be used for the animation

5 4) In the Loading a strip image pop-up box, enter the following: Number of images: 3 Images per row: 3 Image width: 64 Image height: 64 Click OK This creates the 3 sub-images that will be used for the animation

6 5. Click the Show Preview check box to view the animation 6. Click the green check mark icon to save the changes

7 Now we will program the animated helicopters that face the direction of the arrow keys located on the side number pad. 7. Right click on the sprite helicopter and find the duplicate function.

8 8. Rename the sprite spr_helicopter_right the picture is not currently facing right that is the next set of directions.

9 9. Click on the Edit Sprite button pulling up the Sprite Editor 10. Click on the Transform menu 11. Select the Rotate function

10 12. Set the angle to 90 degrees (is the helicopter facing right?) 13. Make sure this Applies to all images in the sprite 14. Click OK

11 15. Click the checkmark to save 16. Click the OK button to save

12 Repeat the procedure to create your left (180 degrees) and down sprite (270 degrees). Make sure, at this point, to rename the original sprite spr_helicopter_up

13 Programming the NEW sprites to turn to correct direction 1) Create an obj_helicopter 2) Create all these events (we will use the number keypad to control the helicopter (include a <no key> event).

14 Using the 8 key (up) as an example, to program: Select the Change Spite action from the Main 1 folder Select spr_helicopter_up as the image, enter 0-2 subimage, and speed 1 Note: Specifying subimage 0-2 creates the animation. The computer is continually displaying subimage 0, subimage 1, subimage 2. (helicopter blades in different locations)

15 The second action is to actually create the movement and direction with the Move Fixed action.

16 Now, create a helicopter that flies and points in 8 directions (using the numeric keypad) You will also need to add 4 more sprites at 1, 3, 7, and 9 positions And the 5 key will be used for..... firing

17 Part 2: Programming the ability to shoot (in all directions). Add a create event. Add action Set Variable. Call it angle_of_bullet. The sprite helicopter is facing up so the initial value should be 90 (degrees).

18 In Game Maker the program interprets degrees like the figure below

19 In the case of number 1 on the keypad, the direction of the helicopter is facing 225 degrees, so the variable angle_of_bullet needs to be set at 225 degrees. Set all the keypads (EXCLUDING #5) to their proper degrees

20 Call up the #5 key this is our trigger. The key action is called Create Moving. This will create an obj_bullet at the center of the sprite. It will be heading in the direction of angle_of_bullet at a speed of 10. Since we don t have any type of delay, the bullets come out as a stream of bullets.

21 Many of the objects you will program will have bullets coming out, not at the center, but at the edges.

22 When the bullet comes from 0,0 it s easy to program it always stays at 0,0. But when you have 2 bullets, and the helicopter is facing up one bullet comes from -10 (x),0 (y) and one bullet comes from +10 (x), 0 (y). 0,0-10,0 +10,0

23 But when the helicopter is facing right one bullet comes from -0 (x),10 (y) and one bullet comes from 0 (x), +10 (y) x and y are switched.

24 And what about the 45 degree shots... ALL can be solved with a formula: x= 16*cos((obj_helicopter.angle_of_bullet+270)*pi/180) Bullet 1 y= 16*-sin((obj_helicopter.angle_of_bullet+270)*pi/180) x= 16*cos((obj_helicopter.angle_of_bullet+90)*pi/180) Bullet 2 y= 16*-sin((obj_helicopter.angle_of_bullet+90)*pi/180)?,? 0,0?,? That s why it s important to take math classes (trigonometry)

25 Finished Product

26 Part 3: Something to shoot at? How about random Hot Air Balloons?

27 Load the balloon sprite from the file. Make it into obj_balloon. To program balloons appearing at random points along the top of the screen. 1) An object controller needs to be created (obj_controller_balloon) 2) Use a Create EVENT to create a balloon somewhere off the top of the screen: x=random(room_width), y=-16.

28 Set an alarm (Alarm 0) action to go off after 50 steps. This will activate Event #2 the Alarm 0.

29 And when the Alarm goes off what happens? It will do 2 things: 1) Create a new instance (same x,y coordinates (x = random(room )) 2) Reset the alarm for another, in this case, 100 steps.

30 How are the actual balloons programmed? 1) Create EVENT: Set Vertical Speed to 1.

31 2) Step EVENT (always checking): Check Variable to see if y is larger than room_height (the +32 allows the balloon to completely float off the screen before it does the next item) Jump to Position action (where it restarts at the top of the room).

32 3) The last EVENT if the balloon Collides with a bullet what do you want to happen? It could just disappear (destroy instance of self (balloon) and a 2 nd destroy instance (other the bullet)). Why not obj_bullet it will destroy ALL bullets on the screen.

33 What is this Change Instance? If you want the balloon to be destroyed in a massive explosion you create an explosion sprite strip create explosion object Animate it (EVENT) and then destroy it.

34 Moving Rooms?

35 The President of the United States has come to stay on your tropical Island. Terrorists (hot air balloonists) want to destroy your island. Your Assignment is to create a game in which you protect your island from any wayward hot air balloonists and thus save the President! Requirements: Helicopter must fly and fire in all 8 directions. Program balloons to be coming from at least 3 different sides of the screen (each will be a different color combination). They will reset randomly if not destroyed. Create an explosion sprite with multiple subimages. If the balloons touch the island, the island disintegrates into a massive explosion. Make sure to put the controller in the room!!!!