Gyruss: Routine at 99B1

99B1: Shot hit mine

Used by the routine at handle_shot_collision.

Input
IX	Sprite data of shot
IY	Mine data

shot_hit_mine

99B1

LD D,$0F

Color

99B3

CALL remove_shot

Remove shot

99B6

LD A,(IY+$06)

Get mine data ?

99B9

CP $80

If not $80

99BB

JR NZ,shot_hit_mine_0

Then jump ahead

99BD

LD A,$08

Play sound

99BF

CALL call_play_sound

...

99C2

LD A,(other_flags)

If double shot is enabled

99C5

BIT 1,A

...

99C7

JR NZ,shot_hit_mine_0

Then skip offering double shot

99C9

LD HL,offset_double_shot_flag

Set flag for offering double shot

99CC

SET 0,(HL)

...

99CE

LD DE,$0500

Points

99D1

JR shot_hit_mine_1

Jump ahead

shot_hit_mine_0

99D3

LD A,$04

Play sound

99D5

CALL call_play_sound

...

99D8

LD HL,mines_destroyed

Get mines destroyed

99DB

LD A,(HL)

...

99DC

INC (HL)

Increment mines destroyed

99DD

ADD A,A

x2

99DE

LD HL,score_table

Score table

99E1

RST $08

Add A to HL

99E2

LD D,(HL)

Get points (hundreds)

99E3

INC HL

Next address in table

99E4

LD A,(HL)

Get points sprite type ($06 - $0B)

99E5

LD (IX+$06),A

Save in sprite data

99E8

LD E,$00

LSB of points

This entry point is used by the routine at shot_hit_mine.

shot_hit_mine_1

99EA

PUSH DE

Save score

99EB

LD (IY+$04),$00

Remove mine

99EF

LD (IY+$05),$00

...

99F3

PUSH IX

99F5

CALL display_background_patterns

Display background patterns

99F8

LD HL,mines_left

Decrement mines left

99FB

DEC (HL)

...

99FC

JR NZ,shot_hit_mine_2

Skip ahead if any left

99FE

LD HL,other_flags

Clear mines flag

9A01

RES 2,(HL)

...

shot_hit_mine_2

9A03

POP IX

9A05

POP DE

Restore score

9A06

JR add_points_in_de

Add points to score