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291 Final Project:
Mission Impossible
Team Members:
Ka Chun Ma -- Graphics
Ryan Tam -- AI
Shoko Oono -- Game Main
Richard Rittis -- Sound
Introduction:
The goal of the game is for Tomy to successfully download 5 separate parts of the mp from his classmate's computer without being caught by a TA. Tomy must travel, starting from his own computer, across the screen to his classmate's computer and then make the trip back, once he has one of the parts of the mp on his disk. There will be two TA's, one at the top and one at the bottom of the screen. They will roam left and right. They will be designed to pause for a moment before turning to look at Tomy. At this time, when a TA looks at Tomy, Tomy must turn and hide the disk, otherwise, he will have been caught. In order to hide the disk, Tomy must turn away from the TA. The two TA's will never look at Tomy at the same time, because there is no way Tomy can hide the disk from both TA's at once. Once at a computer, it takes time to download or upload the piece of the mp onto or off of his disk. A countdown will start. If Tomy chooses to hide his disk during this time, the countdown will stop, and it will resume once Tomy returns to the proper position for downloading or uploading. Each portion must be downloaded or uploaded completely for it to count towards the total of 5 parts.
Tomy's movement will be limited to the center portion of the screen, a rectangle starting at (50, 60) with height 100 and width 220, and the TA's can only move horizontally. To move Tomy, the player can click with the left mouse button in a valid area of the screen and Tomy will move towards that position. To make Tomy turn, click with the right mouse button, above or below him, and he will turn in that direction. Making Tomy turn will also stop his movement to whatever destination was previously designated by the left mouse button. In order to download or upload from a computer, the player must click on a computer, and if Tomy is close enough to the computer, he will be moved into the proper place for downloading or uploading.
Goals:
-Game is in 320x200 VGA.
-Write an AI which does not cause contradictions within the
game and yet be not too
easy to predict its next move.
-Provide support for the use of a mouse.
-Provide background music and sound effects coordinated
with events within the game.
Problem Description:
Sound
In this program
we will be using both MIDI sound files and unformatted
sound files to enhance the game playing environment. The
game uses the MIDPAK API by John W. Ratcliff to play a MIDI file
in the background to enhance game play and to set the proper
mood. The implementation of the Midi sequences is
straightforward and easy to implement although the documentation
is not too clear at times.
Implementing voices and sound effects was the more troublesome of the sound implementation tasks. The documentation for playing digitized sounds is not as clear and the methods are numerous. Special attention will have to be paid to ensuring the correct priority for sound files, so sound is in synch with game play.
TAControl
For the movement of
the TAs, random number is used to decide what the next action of
the TAs would be. Random number generation has been given
in the earlier semester's mp,
and here is just the method that was presented in the mp.
R(1)=RandSeed
R(i+1) = RandSeed = (
K1 * R(i) + K2 ) % MaxValue
where:
R(i) is the random
value generated in the i-th call to the subroutine.
RandSeed is a variable
that holds the initial random value and is updated with the
result after each call to Random.
K1 and K2 are two
large, prime-valued constants, defined as 55821 (0DA0Dh) and 1
respectively.
MaxValue = 2^16-1
(0FFFFh)
For our project, the
TAs turn their heads whenever the random number falls into the
range that we've been set up for the motion. The range of
the random number for turning the
head of the top TA is between 5500h -- 7500h. While the bottom TA
is in between 8800h and 9000h. Also, the TAs would stop for a
while before they turn, that way it would give Tomy time to
respone once he notices that the TAs are goning to turn. Of
course the TAs won't turn their heads at the same time because
there would be no way for Tomy to avoid being caught.
Mouse Control
In order to make the
mouse driver to something more than its pre-existing functions
offer, one way to do it would be to write your own driver.
However, because the mouse is very complicated, there would be
much that would have had to be rewritten, just to add that one
function to the mouse driver. Instead, function 000Ch can
be used. This function tacks on a "handler" to
the original mouse driver. Therefore, the mouse driver will
work as always, including all of its functions, but with that
added "handler" function. In this way, the mouse
status variables are changed whenever the mouse has been moved or
a button on it had been pressed. The mouse
"handler" for this specific game will be written to
change the outside status variables whenever a button on the
mouse has been pressed.
Graphics Implementation
We will be using four segments to hold all the images and
background.
--ForeSeg holds foreground images such as TA's image, Tomy's
image.
--BackSeg conatins the background which won't be change very
often.
--ImageSeg conatins the data from BackSeg and ForeSeg before
writing to screen.
--ScrSeg - segment which LoadPCX and LoadSound
Most of the images will be 60 X 60 pixel besides the background and the downloading bar. To allocate the source of the picture in the PCX file, the look up table would be the best choice.
One way
to give the illusion of the depth of the game, is to use ZBuffer
as we did in MP4. But I chose not to keep track of
all the z-value of all pixel on the screen, instead we draw
the images in a desired sequence. For example, having TA1's leg
covered by Tomy's head as he walks close to him, we need to
display the TA's image on the ImageSeg first, so that TA's leg
will be drawn over by Tomy's imgae.
Variables:
Segments:
-ForeSeg - segment to which people are drawn to
-BackSeg - segment holds background image
-ImageSeg - segment to which conatins the data from BackSeg and
ForeSeg before writing to screen.
-SBSeg - segment for outputting to the screen
-ScrSeg - segment which LoadPCX and LoadSound
-GameMidiSeg - holds game play theme song
-SoundSeg1 - for soundeffects during game play
Global Variables:
sound:
-GameSong - contains game song (the ever-moving Mission
Impossible theme song)
-SoundFile - contains sound to be played
-GameMidiSeg - holds GameSong
-GameSong - offset of MIDI file within GameMidiSeg
-DMAChannel - 8-bit DMA channel for sound card.
Detected and set by SetSoundCardData.
-IRQ - IRQ for sound card. Detected and set by
SetSoundCardData.
-SoundBaseAddr - Sound card base address. Detected
and set by SetSoundCardData.
-ABuffer - used for converting ASCII base address to hex.
-Blaster - stores string to look for in 'set.txt' file for
setting sound card parameters
-BlasterFile - points to 'set.txt' file
-TimeConstant db 165 = 11KHz time constant for DSP
programming
-OldSoundV - contains the old interrupt vector for sound IRQ
-IRQint - Interrupt adjusted for IRQ acknowledgement
-sound - (1 = sound card installed, 0 = no sound card)
-DMAPage - the calculated page used for DMAC programming
-DMAOffset - calculated offset used for DMAC programming
-DMAPageReg - page register for respective DMA channel for DMAC
programming
-DMAOffsetReg - offset register for respective DMA channel for
DMAC programming
-DMALengthReg - length register for respective DMA channel for
DMAC programming
These variables point to the respective sound file to be played
during the game.
-Perfect - 'itsprfct.pcm'
-DeepDoo - 'yrndpdo.pcm'
-Xferred - 'b5xfer.pcm'
-Beating - 'beating.pcm'
-ThemeFile - 'mission.xmi', themesong filename
-ThemeSize - file size set during file loading
-FileSize - sound file size used to program sound playback, set
during file loading
control:
-LeftButton - boolean value (cleared when accessed)
-RightButton - boolean value (cleared when accessed)
-MouseX - x location of mouse when a button was last pressed
-MouseY - y location of mouse when a button was last pressed
-tomx - previous x location of Tomy
-tomy - previous y location of Tomy
-newtomx - next x location of Tomy
-newtomy - next y location of Tomy
-tompic - holds picture number for Tomy
-tompos - holds offset for Tomy's next position
-tomDir - direction of Tomy(used by the jump function)
-LineArray - array of 200 words that hold x values for
corresponding y's
-NextX - next immediate destination point for Tomy (x)
-NextY - next immediate destination point for Tomy (y)
-picNum - index to the offset of a pcx file
-TA1pic - holds picture number for TA1
-TA1pos - holds offset for TA1
-TA1old - TA1's old picture number (tells what TA1 was doing
before, but not the turning pic)
-TA1stop - countdowns pause time for TA1
-ta1pause - indicator for the pausing of TA1
-ta1look - countdowns for how long TA1 looks at Tomy
-TA2pic - holds picture number for TA2
-TA2pos - holds offset for TA2
-TA2old - TA2's old picture number (tells what TA2 was doing
before, but not the turning pic)
-TA2stop - countdowns pause time for TA2
-ta2pause - indicator for the pausing of TA2
-ta2look - countdowns for how long TA2 looks at Tomy
-stole - boolean value (set when Tomy steals first piece - from
here on, Tomy can be caught)
-dead - incremented as Tomy get caught
-Randseed - for random number generator
-randstate - switch between adding tomX and tomY as the input for
the random function
-xst - the x-coordinate of the point with the lower y value
-xnd - the x-coordinate of the point with the greater y value
-yst - the y-coordinate of the point with lower y value
-ynd - the y-coordinate of the point with higher y value
-ydiff - the difference between two y values of two pixels
-drawxpos - the new x-position of the scaled pixel
-drawypos - the new y-position of the scaled pixel
-vertcount - counting from 0 to 200
-horizoncount - counting from 0 to 320
-scaleX - x-coordinate of each pixel of the pcx file starting
from 0 to 319
-scaleY - y-coordinate of each pixel of the pcx file starting
from 0 to 199
-shrink - for how much the pcx file is goning to be scaled to
-shift - offset of the scaled pcx
-flying - offset of 'flying Tomy' in the ending animation
-zsleep - for which 'z' is displayed on the screen
-OldTimerV - address of old timer handler
-Count - counter to set pace of game by
graphics:
-pbuf - used in DrawCount
-pos - stores offset position
-counter - initialize counter for fist download
-download - 1= Download, 0=Upload
-completed - 1 = score is 5, 0 = socore<5
-InorOut - use in checkarea, 1 = in, 0 = out
-Score - holds the number of disks to be drawn
-barPos - lenght of downloading bar
-leftpos - use in split screen, lenght of left half of screen
-rightpos - use in split screen, lenght of right half of screen
-splitSpeed - speed of spliting screen
Constant:
-P2_U, P2_D, P2_R, P2_L - for the keyboard control
-CountDownLoad = undecided (value from which LoadCount counts
down)
-CountDownTA = undecided (value from which TA1stop and TA2stop
counts down)
-TomCompX = x location of Tomy for when uploading to his computer
-TomCompY = y location of Tomy for when uploading to his computer
-MateCompX = x location of Tomy for when downloading from his
classmate's computer
-MateCompY = y location of Tomy for when downloading from his
classmate's computer
-MaxValue = 2^16
- K1 - 55821
-Zpos1 - constant for the offset of 'z'
-Zpos2 - same here
-Zpos3 - same here
ScreenShots:
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Game's Background
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TA at the top of the screen. (actual size 60 X 60 pixel)
Procedures:
Graphics:
1.MoveImage-
Ka Chun Ma
Purpose:
transfer the image in a given segment to another segment.
Description: For example, it could place the background from
the BackSeg to the ImageSeg which
will later merge with the ForeSeg.
Input: none
2.DrawScreen- Ka Chun Ma
Purpose: Display all images in the ImageSeg to the screen
input: none
Output: Write to screen
3.LoadPCX- Ka
Chun Ma
Purpose: Loads and decodes a 320x200 PCX file into a
specified Seg and maps the RBG color
component from 8 bits to 6 bits registers.
Description:
This function is derived from the lab manual.
Input: AX - Segment in the memory where the image goes to.
DX - offset
Output: set the VGA palette register.
load the ImageSeg with the decoded image.
4. DrawCount - Ka Chun Ma
Purpose:
Display numbers on ImageSeg, calls BINASC. calls ScanImage.
input: Count = number, which is the Downloading
counter.
Output: write to ImageSeg
5.ScanImage - Ka Chun Ma
Purpose:
Scan desire image located a given segment to another segment at a
given location
: Scan all size of all images. Draw non-white pixel only.
input: Source = segment that holds that image, 0
= ForeSeg, 1 = Scratchpad
: Dest = segment that will store the
image, 0 = ImageSeg, 1 = BackSeg
: position = offset of the image to be displayed in Dest segment
: H, W = height and width of image
: pic = index of picture in the
look up table (picNum)
Output:
move images from one seg to another
note: More arguments are
added compared to the first version.
This make it easier to find the changing offset in the
"SplitScreen" function.
e.g. if pic > 75, pic = offset of image != index of picNum
(*)
notation means new added function that wasn't in the first write
up
6. DrawScore - Ka Chun Ma (*)
Purpose: Draw
little disk at the status bar (bottom of screen)
input: Score = number of pieces of MP
Output: write to BackSeg
7. DrawSkull- Ka Chun Ma (*)
Purpose: Draw
little skull at the status bar. Similar to DrawScore.
input: Score = number of "caught"
Output:
write to BackSeg
8. WaitTimer - Ka Chun Ma (*)
Purpose: Give
pause between drawing things. Used in Opening function.
input: howLong = how long is the pause.
Output: none
9. Opening - Ka Chun Ma (*)
Purpose: The
title screen. Calls SplitScreen and end with option Screen.
input: none
Output: Write to Screen
10. SplitScreen - Ka Chun Ma (*)
Purpose: Split screen into half slowly with a background image behind it
input: ImageBuffer should contain images for spliting
BackBuffer should contain the desire background.(loadPCX
file into BackBuffer)
Output: write to ImageSeg and BackSeg;
: transfer the background from BackBuffer to Imagebuffer at the
end
note: must call install timer before calling this function since
it uses WaitTimer.
11. CheckArea - Ka Chun Ma (*)
Purpose: Check if Tomy is at the right place for downloading and
uploading.
input: dimension of a Rectangle
Output: Set InorOut = 1 if in. Set InorOut = 0 if out.
12.CheckDownload - Ka Chun Ma (*)
Purpose:1.Check for downloading and uploading. If download or
uploading,
dec counter and display it.
2.Once finish downloading, avoid "re-download".
Likewise for upload.
3.Draw Download Bar on the ImageSeg.
4.Keep track of Score.
5.Earse Bar and Counter on Screen when quit.
Input: tomypic = 9, download; 8 = upload
dowload = 1, download; 1 = upload. Avoid re-download
Output: Draw Count, Score and download bar. Set tomypic =
face down when finish
Reset count when quit.
13. InitWhite-Ryan
Tam
Purpose:
This routine initializes all the bytes in the Scratchpad to
white.
Inputs: none
Outputs: reset the all the bytes in the Scratchpad to 0D7h
14. InitWhite-Ryan
Tam
Purpose:
This routine initializes all the bytes in the ImageBuffer to
black.
Inputs: none
Outputs: reset the all the bytes in the ImageBuffer to 00h
15. Random-Ryan
Tam
Purpose: This routine generates a pseudo-random number
by multiplication and addition of large prime
constant to a random number.
Inputs: randseed, tomx, tomy
randstate: if randstate = 1, add the variable tomy as the input
if randstate = 0, add the variable tomx as the input
Outputs: Randseed = Random number between 0 .. 2^16-1
Description: This function is adopted from previous MP
16. TopTAControl -Ryan
Tam
Purpose: have the computer decide the movement and action of
TA1
Description: This routine calls the random AI so that the TA
on the top would move, stop and turn according to the output of
the random function
Inputs:
TA1pic - the previous direction of the top TA
ta2pause - see if the other TA is pause at this time
ta1look - a counter for how long the TA is looking at Tomy
ta1stop - a counter for how long the TA stops before he turns
Outputs:
TA1pic - the next motion of the TA
TA1pos - the offset of the top TA on the screen
ta1old - saves the TA1pic when the TA doesn't stop or turn
17. TA1turn-Ryan
Tam
Purpose:
This routine set the variable for the top TA when he stops.
Inputs: randseed
Outputs: ta1pause
Description: This routine is called by the TopTAControl
and gives signal to the caller function when the top TA needs to
turn.
18. BottomTAControl -Ryan Tam
Purpose:
have the computer decide the movement and action of TA2
Description:
same as TopTAControl
Inputs:
TA2pic - the previous direction of the top TA
ta1pause - see if the other TA is pause at this time
ta2look - a counter for how long the TA is looking at Tomy
ta2stop - a counter for how long the TA stops before he turns
Outputs:
TA2pic - the next motion of the TA
TA2pos - the offset of the top TA on the screen
ta2old - saves the TA1pic when the TA doesn't stop or turn
19. TA2turn-Ryan
Tam
Purpose:
This routine set the variable for the bottom TA when he stops.
Inputs: randseed
Outputs: ta2pause
Description: This routine is called by the BottomTAControl
and gives signal to the caller function when the bottom TA needs
to turn.
20. Caught -Ryan
Tam
Purpose:
check to see if Tomy is being caught by one of the TAs
Inputs:
stole, tompic, TA1pic, TA2pic
Outputs:
increment dead when Tomy is caught by the either one of the
TAs
21. Arrangepts-Ryan
Tam
Purpose:
This routine rearranges any two points on the decoded pcx file.
Inputs: X1, Y1, X2, Y2
Outputs: xnd and ynd - the point that has a higher y value
xst and yst - the point which has a lower y value
Description: This routine rearranges any two points with
respect to their y-value.
22. Scaling-Ryan
Tam
Purpose:
This routine puts a pixel in the decoded pcx file and put it in a
new position depending on the variable scale.
The range for the scaling factor is from 0 to 255.
Inputs: xst, yst, xnd, ynd
scale = how much the pcx file is going to be scale
Outputs: drawxpos = the new x-position that the same pixel
has to be drawn
drawypos = the new y-position that the same pixel has to be drawn
Description: This routine first calculates the slope
between the pixel you want to relocate and the center pixel, and
multiplies
it by whatever scale you want to use.
23. DrawScale-Ryan
Tam
Purpose:
This routine put every pixel on the pcx to a new position in the
Scratchpad
Inputs:scaleX - x-position of the pixel that is going to be
scaled
scaleY - y-position of the pixel that is going to be scaled
Outputs: pixels are placed in the scaled position on in the
buffer
Description: This routine calls Scaling and loops through
the entire 320x200 pcx file and scales every pixel.
24. EndingScreen-Ryan
Tam
Purpose:
This function outputs the ending animation to the screen which
also with sound associated with it.
Inputs: shrink - for how much the pcx is shrink
shift - for how much the scaled pcx is placed away from the
previous drawn picture
Outputs: the entire ending animation
Description: This routine calls InitWhite, InitImage,
WaitTimer, playbeating, ScanImage, DrawScale and DrawScreen
and mix them all up for the entire animation.
MIDI Sound
25. RegisterXMIDI -Richard
Rittis
Purpose:
Registers XMIDI data.
Inputs:
CX - Segment address of MIDI segment.
BX - Offset of midi file.
Outputs:
none
Description:
This function stores the XMIDI data to be played in Midpak's
interal buffer by using the
MIDPAK driver function 704h on INT 66h.
26. PlayTheme-Richard
Rittis
Purpose: Play the currently registered midi file.
Outputs: sound (midi file)
Description: This function starts the playing of a selected
midi file by using the MIDPAK driver
function 702h on INT 66h.
27. StopMIDI-Richard
Rittis
Purpose: Stops playing the xmidi file.
Description: This function uses the MIDPAK function 705h on
INT 66h.
28. ResumeMIDI-Richard
Rittis
Purpose: Resumes playing a stopped midi sequence.
Description: This function uses the MIDPAK function 70Bh on
INT 66h.
29. CheckMIDIStatus-Richard
Rittis
Purpose: Checks the status of the xmidi file play process.
Description: This function uses the MIDPAK function 70Ch on
INT 66h.
VOICE/SOUND EFFECT sound
30. InstSound -Richard
Rittis
Purpose:
Installs new vector for ISR.
Inputs:
None
Outputs:
Sets OldSoundV.
Description:
Saves old sound card interrupt vector and installs sound
card IRQ vector .
31. DeInstSound -Richard
Rittis
Purpose:
Reinstalls original vector for sound card IRQ ISR.
Inputs:
None
Outputs:
Restores interrupt vector to original.
Description:
uses OldSoundV.
32. MySoundHandler -Richard
Rittis
Purpose:
ISR to acknowledge IRQ and send EOI command to Master/slave PIC .
Inputs:
None
Outputs:
EOI command to PICs, read command to acknowlege the DSP.
Description:
DSP only requires a read command to acknowledge interrupt.
If IRQ
is greater than 7, then it also sends EOI to slave PIC.
33. SetSoundCardData -Richard Rittis
Purpose:
Read the sound card settings from the environment PSP.
Inputs:
None
Outputs:
Sets DMAChannel, IRQ, and SoundBaseAddr.
Description:
Calls LoadSound to load the SET.TXT file into
memory. Scan through the DOS environment
data located in the file SET.TXT until it finds BLASTER
section. Retrieves and sets the information;
SoundBaseAddr = A### (base address), IRQ = I# (interrupt), and
DMAChannel = D# (DMA).
Also Calculates IRQint which is dependent upon IRQ.
34. LoadSound-Richard
Rittis
Purpose:
Load a selected unformatted file to Buffer.
Inputs:
DX - Offset to string.
Outputs:
Loads the segment, returns AX = FileSize.
Description:
It utilizes DOS function to open file into the buffer and updates
the file pointer.
35. ResetDSP-Richard
Rittis
Purpose:
Reset/Initialize the DSP.
Inputs:
SoundBaseAddr
Outputs:
None.
Description:
Prior to using (programming) the DSP, it must be
reset/initailized. This is done by sending
a ‘1’ to the Reset port (2x6h), waiting 3 seconds, and
then sending a ‘0’ to the port. After
approx. 100 us, the DSP should be reset. This can be
verified by polling for a ready byte (AAh)
from the Read Data port (2xAh) when a ‘1’ is received
at the Read-Buffer Status port (2xEh).
36. ReadDSP-Richard
Rittis
Purpose:
Read the DSP.
Inputs:
SoundBaseAddr
Outputs:
None.
Description:
When read buffer status port (2xEh) contains a ‘1’,
this command reads data in read data port (2xAh).
37. WriteDSP-Richard
Rittis
Purpose:
A C-style function write to the DSP.
Inputs:
Command.
Outputs:
Writes to DSP.
Description:
Reads Write-buffer status port. Sends command to DSP write buffer
status port when DSP is ready.
38. InitDMAC-Richard
Rittis
Purpose:
Sets up the DMA Controller in preparation for a transfer.
Inputs:
DMAChannel
Outputs:
Set DMAC
Description:
Calculates Page and offset, MASK DMA channel, RESET, write the
transfer MODE,
DMA_PAGE, DMA_OFFSET and DMA_LENGTH, then DEMASK channel.
39. PlaySound-Richard
Rittis
Purpose:
A C-style function to play the desired sound file.
Inputs:
offset of sound file, segment of sound file (usually SoundSeg1),
length of file
Outputs:
Plays sound
Description: Turn
Speaker on, Set TIME_CONSTANT, HIGHSPEED, AUTOINIT, buffer size
and
play MODE, turn speaker off.
40. SetVolume-Richard
Rittis
Purpose:
Sets the volumes of the various mixer channels
Inputs:
none
Outputs:
sound levels on mixer channels set
Description: Calls MixerSet.
41. MixerSet-Richard
Rittis
Purpose:
Sets the mixer register to the value passed to it.
Inputs:
MixerRegIndex, MixerRegSetting
Outputs:
Sets mixer according to value passed
Description: none
42. CalcLine
purpose -
calculates line from left point to right point
- assumes that RightY is larger than LeftY
- writes x value to corresponding y location in LineArray
inputs -
LeftX, LeftY, RightX, RightY
outputs -
writes to LineArray
43. ClearLine
purpose -
clears LineArray to all zeros
inputs -
no input
outputs -
writes to LineArray
44. StartMouse
purpose -
mouse handler for option screen
- checks for quit and play buttons
inputs -
AX = conditional mask causing call
- BX = button state (0-left button, 1-right button)
- CX = horizontal cursor position
- DX = vertical cursor position
- DS = mouse driver data seg
outputs -
boolean value in quit or play or neither.
45. MouseHandler
purpose - mouse
handler for during game
- checks for all hotspots on screen and returns values
accordingly
- returns fudged location of MouseX and MouseY depending on
location
of mouse and Tomy
- returns boolean values to button variables
- returns boolean value in computer dependent on whether the
computer was
clicked legitimately (i.e. was Tomy close enough to the
computer?)
- returns boolean in quit button if play clicks quit
inputs - AX =
conditional mask causing call
- BX = button state (0-left button, 1-right button)
- CX = horizontal cursor position
- DX = vertical cursor position
- DS = mouse driver data seg
outputs -
MouseX, MouseY, LeftButton, RightButton, computer, quit
46. OffsetCalc-
Shoko Oono
Purpose: calculate offset video memory given x and y
coordinates
Inputs:
-CX = x
-DX = y
Outputs:
-DI = offset in video memory
47. GameMain-
Shoko Oono
Purpose
-control flow of game
-installs and deinstalls timer
-starts and ends background music
-resets mouse and installs handler into mouse
-output opening screen with mouse-selectable choices
-each round, clear score and clear screen to start position
-play soundeffects during gameplay
-during game, refresh screen, move characters, keep track of
characters
-check for game over, and display screen for "game
over"
-return to opening screen after each round
Inputs
-mouse variables (LeftButton, RightButton, etc)
Outputs
-the game
48. Movement- Shoko Oono
purpose - to
plot the next location of Tomy every iteration of GameMain
- calls CalcLine if new destination needs to be plotted
- accesses LineArray to find next destination and then moves to
that point a point at a time for smooth movement
- note - 30 is subtracted from Mouse vars because Tomy's
locations
are at his upper left, whereas he should move directly towards
the mouse
inputs -
MouseX, MouseY, LineArray, NextX, NextY
outputs -
newtomx, newtomy
49. TomyControl -
Shoko Oono
Purpose: Gives the direction of
motion of Tommy for other drawing routines
Description: This function basically gives the drawing
routines information for which pictures of Tommy
they output on the screen.
Inputs: newtomx, newtomy, tomx, tomy
Outputs: tompic, tompos
50. InstTimer -
Shoko Oono
Purpose: installs MyTimerHandler and saves old timer vector
configures timer chip at a suitable pace
Note:
derived from old mp
Input: none
Output: OldTimerV
51. MyTimerHandler-
Shoko Oono
Purpose: increments counter, Count
calls old timer handler 18times per second
sends end-of-interrupt
Note:
derived from old mp
Input: Count and OldTimerV
Output: Count
52. DeInstTimer-
Shoko Oono
Purpose: restores OldTimerV
restores old configurations
Note:
derived from old mp
Input: OldTimerV
Output: none
53. InstKey
Purpose: installs MyKeyHandler and saves the default old
key vector
input: none
output: OldKeyV
54. MyKeyHandler
Purpose: This routine sets escPressed to 1 if the escape
key is pressed sets spcPressed to 1 if the
spacebar is pressed; also sets tomDir to one of UP, DOWN, LEFT,
or RIGHT depending on which keys were pressed
input: none
output: escPressed, spcPressed, TomDir
55. DeInstKey
Purpose: to restore the default keyboard interrupt vector
input: OldKeyV
output: none