Wednesday Workshop

-=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- (c) WidthPadding Industries 1987 0|599|0 -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=- -=+=-
Shoot-Em-All

by mike_g for Workshop #152
Shoot the Invaders!
Cursors and Spacebar
Graphics 320, 240, 32, 2
SetBuffer BackBuffer()

Const NUM_STARS = 120
Const DARKEN = 10
Const TRAIL_SIZE = 5
Const PIC_PLAYER = 1
Const PIC_GREENIE =2 
Const PLAYER_SPEED =2

Const SHOT_BULLET = 0
Const SHOT_FLAME = 1
Const SHOT_LASER = 2

Dim pics(4) ;Image Handles

Type star
	Field x#, y#, z
End Type

Type alien
	Field x, y
	Field health
	Field pic
End Type
Global a_counter, a_inc=1

Type fire
	Field x, y
	Field side
	Field spd
	Field kind
End Type

Type player
	Field x, y
	Field counter
	Field lives
	Field level 
	Field score
	Field shot
End Type

Type frag
	Field x#[TRAIL_SIZE]
	Field y#[TRAIL_SIZE]
	Field direction
	Field speed
	Field falloff
End Type 

Dim palette(256)
For i = 0 To 256
	r=r+5:	g=g+3:	b=b+2
	If r > 255 Then r=255
	If g > 255 Then g=255
	If b > 255 Then b=255
	palette(i) = (r Shl 16)+(g Shl 8)+b
Next

Dim sine#(360), cosine#(360)
For i = 0 To 360
	sine#(i)=Sin(i)
	cosine#(i)=Cos(i)
Next

InitStarField()
CreateSprites()
InitGame()
InitLevel()

Repeat
	Cls 
	StarField(4)
	DrawSprites()
	DrawShots()
	Collision()
	DrawExplosions()
	MoveSprites()
	PlayerInput()
	UpdatePlayer()
	Flip
Forever

;------------------------------------------------;
;************** STAR FIELD **********************; 
;------------------------------------------------;
Function StarField(speed#)
	LockBuffer
	For s.star = Each star
		s\y# = s\y# + Float(s\z) / 500.0 * speed#
		If s\y# > GraphicsHeight()-1
			s\y#=-1
			s\x#=Rnd(0, GraphicsWidth()-1)
			s\z=Rand(0, 255)
		Else
			WuPixel(s\x#, s\y#, s\z)
		EndIf 
	Next	
	UnlockBuffer
End Function

Function InitStarField()
	For i = 1 To NUM_STARS
		s.star = New star 
		s\y#=Rnd(0, GraphicsHeight()-1)
		s\x#=Rnd(0, GraphicsWidth()-1)
		s\z=Rand(0, 255)		
	Next
End Function 

Function WuPixel(x_pos#, y_pos#, brightness)
	Local i_x% = Floor(x_pos#)
	Local i_y% = Floor(y_pos#)
	Local f_x# = x_pos# - i_x
	Local f_y# = y_pos# - i_y
	Local t_l% = (1.0 - f_x#) * (1.0 - f_y#) * brightness
	Local t_r% = f_x# * (1 - f_y#) * brightness
	Local b_l% = (1.0 - f_x#) * f_y# * brightness
	Local b_r% = f_x# * f_y# * brightness
	
	WritePixel(i_x, i_y, t_l + (t_l Shl 8) + (t_l Shl 16))
	WritePixel(i_x+1, i_y, t_r + (t_r Shl 8) + (t_r Shl 16))
	WritePixel(i_x, i_y+1, b_l + (b_l Shl 8) + (b_l Shl 16))
	WritePixel(i_x+1, i_y+1, b_r + (b_r Shl 8) + (b_r Shl 16))
End Function 
;------------------------------------------------;
;************** LOAD IMAGES *********************; 
;------------------------------------------------;
Function CreateSprites()
	pics(1) = CreateImage(12, 12)
	MakeSprite(pics(1), $FFAAAAAA)
	pics(2) = CreateImage(12, 12)
	MakeSprite(pics(2), $FF2222AA)
	pics(3) = CreateImage(12, 12)
	MakeSprite(pics(3), $FF779922)
	pics(4) = CreateImage(12, 12)
	MakeSprite(pics(4), $FF772299)
End Function 

Function MakeSprite(sprite_han, col)
	For y=0 To 11
		bit=1
		Read scan_line 
		col = Darken(col)
		For x=0 To 11
			If scan_line And bit Then WritePixel(x, y, col, ImageBuffer(sprite_han)) 
			bit = bit Shl 1	
		Next
	Next
End Function

Function Darken(col)
	r = ((col Shr 16) And 255) - DARKEN
	If r < 0 Then r = 0
	g = ((col Shr 8) And 255) - DARKEN
	If g < 0 Then g = 0
	b = (col And 255) - DARKEN
	If b < 0 Then b = 0
	Return (r Shl 16) + (g Shl 8) +b
End Function

Data 96, 240, 144, 1170, 1434, 1530, 4095, 3315, 4095, 2046, 924, 780    ;Player
Data 240, 504, 1020, 1266, 3315, 4095, 4095, 1020, 504, 1020, 1782, 2709 ;Invader
Data 2049, 2289, 2046, 1638, 2046, 3591, 3075, 3075, 3591, 1542, 780, 408;Biter
Data 504, 3069, 3069, 4095, 3171, 3687, 4095, 3075, 3591, 3069, 3069, 504;Blocker

;------------------------------------------------;
;************** INIT STUFF **********************; 
;------------------------------------------------;
Function InitGame()
	p.player = New player
	p\lives = 3: p\level = 1: p\score = 0
	
End Function 

Function InitLevel()
	p.player = First player 
	p\x = 154: p\y = 210
	For y=0 To 5+level
		For x=0 To 14
			a.alien = New alien	
			a\x=x*16+2: a\y=y*16+2
			If y < 2
				a\health = 3
				a\pic=pics(2)
			Else If y < 4
				a\health = 2
				a\pic=pics(3)
			Else
				a\health = 2
				a\pic = pics(4)
			EndIf 
		Next
	Next
End Function
;------------------------------------------------;
;**************** SPRITES ***********************; 
;------------------------------------------------;
Function DrawSprites()
	For a.alien = Each alien
		DrawImage a\pic, a\x, a\y
	Next
	For p.player = Each player
		DrawImage pics(1), p\x, p\y 
	Next
End Function 

Function DrawShots()
	LockBuffer
	For f.fire = Each fire
		Select f\kind
		Case SHOT_FLAME
			WritePixel f\x, f\y, $FF22FF88
			WritePixel f\x, f\y+1, $FF228844
		Case SHOT_BULLET
			FlameShot(f\x, f\y)
		End Select
		f\y = f\y + f\spd
		If f\y < 0 Or f\y > 239 Then Delete f.fire 
	Next
	UnlockBuffer 
End Function 

Function FlameShot(x_pos, y_pos)
	For y = 0 To 3
		For x=0 To 5
			WritePixel(x_pos+x, y_pos-(x/2)+y, palette(120-(y*40)))
			WritePixel(x_pos+6+x, y_pos-(2-x/2)+y, palette(120-(y*40)))
		Next
	Next
End Function 

Function Collision()
	For a.alien = Each alien
		For f.fire = Each fire
			If f\side = 0
				If ImageRectCollide(a\pic, a\x, a\y, 0, f\x, f\y, 1, 1)
					a\health = a\health-1
					Delete f.fire
					If a\health < 1
						NewExplosion(a\x+6, a\y+6, Rand(50, 250), 5)
						Delete a.alien
						Exit 
					EndIf 
				EndIf  
			EndIf 
		Next 
	Next
End Function

Function MoveSprites()
	For a.alien =Each alien 
		a\x=a\x+a_inc
	Next
	a_counter = a_counter + a_inc
	If a_counter > 80 Or a_counter < 0  
		a_inc =-a_inc
		For a.alien = Each alien 
			a\y = a\y + 2
		Next
	EndIf
End Function

Function UpdatePlayer()
	p.player = First player 
	If p\x < 0 Then p\x = 0
	If p\x > 308 Then p\x=308
	p\counter = p\counter + 1
End Function 
;------------------------------------------------;
;**************** INPUT *************************; 
;------------------------------------------------;
Function PlayerInput()
	p.player = First player 
	If KeyDown(203) p\x=p\x-PLAYER_SPEED
	If KeyDown(205) p\x=p\x+PLAYER_SPEED
	If KeyDown(57) PlayerShoot(p.player)
	If KeyHit(25) Pause()
	If KeyHit(1) End
End Function 

Function Pause()
	Text 130, 100, "PAUSED"
	Text 70, 120, "Press Space to resume" 
	Flip  
	FlushKeys 
	While Not KeyHit(57)
		Delay(5)
		If KeyHit(1) End
	Wend
End Function 

Function PlayerShoot(p.player)
	p\counter = p\counter + 1
	If p\counter > 39
		p\counter = 0
		Select p\shot
		Case SHOT_FLAME
			f.fire = New fire
			f\x=p\x+1: f\y=p\y+5: f\spd=-3
			f.fire = New fire
			f\x=p\x+10: f\y=p\y+5: f\spd=-3
		Case SHOT_BULLET
			f.fire = New fire
			f\x=p\x: f\y=p\y+3: f\spd=-2			
		End Select 
	EndIf 
End Function 

;------------------------------------------------;
;**************** EXPLOSIONS ********************; 
;------------------------------------------------;
Function NewExplosion(x, y, frags, range)
	For i = 1 To frags
		e.frag = New frag
		e\direction = Rand(0, 359)
		e\x#[0] = x +cosine#(e\direction)*range
		e\y#[0] = y +sine#(e\direction)*range
		e\falloff = Rand(10, 50)
		e\speed = Rand(1, 2)
	Next
End Function

Function DrawExplosions()
	LockBuffer 
	For e.frag = Each frag
		;DRAW FRAG
		For i = 0 To TRAIL_SIZE
			col = (e\falloff*3)-(i*20) ;/TRAIL_SIZE
			If col < 0 Then col = 0
			WritePixel(e\x#[i], e\y#[i], palette(col)) 
		Next
		
		;MOVE FRAG
		For i = 1 To TRAIL_SIZE-1
			e\x#[TRAIL_SIZE-i]=e\x#[TRAIL_SIZE-i-1]
			e\y#[TRAIL_SIZE-i]=e\y#[TRAIL_SIZE-i-1]
		Next
		
		e\x#[0] = e\x#[0] + cosine#(e\direction)*e\speed	
		e\y#[0] = e\y#[0] + sine#(e\direction)*e\speed

		;FALLOFF
		e\falloff = e\falloff -1
		If e\falloff = 0 Then Delete e.frag	
	Next
	UnlockBuffer 
End Function