Starting from:
$25
CS2261- Lab 02 Solved
Input and Collision
Provided Files
● main.c
● myLib.c
● myLib.h
Files to Edit/Add
● main.c
● myLib.c
● myLib.h
● Your Makefile
Instructions
In this lab, you will be completing several different TODOs, which will, piece by piece, make an interactive rectangle game.
After you download and unzip the files, add your Makefile, add the SOURCES with it, and then compile and run it. At this point, you should see just a blank black screen. Complete the TODOs on order, paying close attention to the instructions.
TODO #1 - drawRect
● Open myLib.c and complete the drawRect function.
● In main.c,find and uncomment UNCOMMENT#1 to see the fruits of your labor. You should see a green rectangle bounce around the screen, and a blue one sit unmoving in its path.
TODO #2
● Head back to myLib.c, find fillScreen (right beneath drawRect) and complete it.
● You may only use a single loop (one for-loop) to complete this one.
● Hint: the index of the top-right pixel is 239, and the index of the leftmost pixel in the next row is 240. Use this concept to your advantage.
● Enter main.c and uncomment UNCOMMENT#2. The background of your game should now be a lovely shade of cyan.
TODO #3
● This one requires a lot of moving parts to work, so it is broken into three parts.
● TODO #3.0
○ Open myLib.h , find the button macros, and complete them.
○ For BUTTON_PRESSED, assume that buttons and oldButtons have been set up appropriately.
● TODO #3.3
○ Since buttons and oldButtons haven’t been set up correctly, head on back to main.c and initialize them in the initialize function.
○ They have already been declared in main.c (and in myLib.h as extern), so you don’t have to worry about that part this time, but you will when you code things yourself for your homework.
● TODO #3.6
○ They still won’t do anything unless you update them each frame, so do that in the main while-loop.
● After you have completed these, find UNCOMMENT #3 in the update function and do the thing.
● Run it, and now you can press Start to toggle the background between cyan and a fabulous bright yellow.
○ Holding down the Start button for a long time should have the same effect as just tapping it a single time. If not, you did one of these three TODOs incorrectly.
TODO #4
● Now that you can take button input, find this TODO in the update function and make it so that the blue rectangle can move up, down, left, and right if you press the corresponding arrow key.
○ This time, it should move for as long as the key is held, meaning that if you tap it once quickly, it will barely move, but if you press it for several seconds, it will move a lot. If not, fix that.
● Compile and run, and you should be able to move the blue rectangle around as you please.
TODO #5
● This one will likely take you the longest, but is also the most important.
● TODO #5.0
○ At the bottom of myLib.c, implement the collision function. It takes in the positions and dimensions of two rectangles, and returns a 1 if they are colliding, or a 0 if not.
○ Hint: draw lots of pictures. Using graph paper, or drawing a grid yourself, is extremely useful. This function should work regardless of the size or velocity of the rectangle (if one is moving).
● TODO #5.5
○ Now that you have it, use it in the update function to make the green rectangle reverse direction when it hits the blue rectangle.
○ The green rectangle will just reverse direction, not properly reflect like it does with the walls.
■ Reflecting properly requires some additional code you won’t have time for in lab, but may need for your homework.
■ Again: your collisions in your homework should not look like this ugly collision here. It will be penalized.
○ If both rectangles are moving, the collision will glitch. Don’t worry about this for now.
■ If you want to fix this, ask in office hours.
○ Compile and run this, verify that it runs correctly, and then you are done.
Provided Files
● main.c
● myLib.c
● myLib.h
Files to Edit/Add
● main.c
● myLib.c
● myLib.h
● Your Makefile
Instructions
In this lab, you will be completing several different TODOs, which will, piece by piece, make an interactive rectangle game.
After you download and unzip the files, add your Makefile, add the SOURCES with it, and then compile and run it. At this point, you should see just a blank black screen. Complete the TODOs on order, paying close attention to the instructions.
TODO #1 - drawRect
● Open myLib.c and complete the drawRect function.
● In main.c,find and uncomment UNCOMMENT#1 to see the fruits of your labor. You should see a green rectangle bounce around the screen, and a blue one sit unmoving in its path.
TODO #2
● Head back to myLib.c, find fillScreen (right beneath drawRect) and complete it.
● You may only use a single loop (one for-loop) to complete this one.
● Hint: the index of the top-right pixel is 239, and the index of the leftmost pixel in the next row is 240. Use this concept to your advantage.
● Enter main.c and uncomment UNCOMMENT#2. The background of your game should now be a lovely shade of cyan.
TODO #3
● This one requires a lot of moving parts to work, so it is broken into three parts.
● TODO #3.0
○ Open myLib.h , find the button macros, and complete them.
○ For BUTTON_PRESSED, assume that buttons and oldButtons have been set up appropriately.
● TODO #3.3
○ Since buttons and oldButtons haven’t been set up correctly, head on back to main.c and initialize them in the initialize function.
○ They have already been declared in main.c (and in myLib.h as extern), so you don’t have to worry about that part this time, but you will when you code things yourself for your homework.
● TODO #3.6
○ They still won’t do anything unless you update them each frame, so do that in the main while-loop.
● After you have completed these, find UNCOMMENT #3 in the update function and do the thing.
● Run it, and now you can press Start to toggle the background between cyan and a fabulous bright yellow.
○ Holding down the Start button for a long time should have the same effect as just tapping it a single time. If not, you did one of these three TODOs incorrectly.
TODO #4
● Now that you can take button input, find this TODO in the update function and make it so that the blue rectangle can move up, down, left, and right if you press the corresponding arrow key.
○ This time, it should move for as long as the key is held, meaning that if you tap it once quickly, it will barely move, but if you press it for several seconds, it will move a lot. If not, fix that.
● Compile and run, and you should be able to move the blue rectangle around as you please.
TODO #5
● This one will likely take you the longest, but is also the most important.
● TODO #5.0
○ At the bottom of myLib.c, implement the collision function. It takes in the positions and dimensions of two rectangles, and returns a 1 if they are colliding, or a 0 if not.
○ Hint: draw lots of pictures. Using graph paper, or drawing a grid yourself, is extremely useful. This function should work regardless of the size or velocity of the rectangle (if one is moving).
● TODO #5.5
○ Now that you have it, use it in the update function to make the green rectangle reverse direction when it hits the blue rectangle.
○ The green rectangle will just reverse direction, not properly reflect like it does with the walls.
■ Reflecting properly requires some additional code you won’t have time for in lab, but may need for your homework.
■ Again: your collisions in your homework should not look like this ugly collision here. It will be penalized.
○ If both rectangles are moving, the collision will glitch. Don’t worry about this for now.
■ If you want to fix this, ask in office hours.
○ Compile and run this, verify that it runs correctly, and then you are done.
1 file (16.9KB)
