Added shot power & fixed point multiply

player.s

@@ -13,7 +13,7 @@ playerData:
 	.word 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0	; Saved background
 
 	.word 45		; Angle in degrees from +X
-	.word 50		; Power
+	.word 2		; Power
 	.word 100		; Anger
 	.byte 8,"SPROCKET "	; Name
 	.word 0,0,0,0,0,0 ;Padding
@@ -23,8 +23,8 @@ playerData:
 	.word 0	; Y pos in pixels (from bottom terrain edge)
 	.word 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0	; Saved background
 
-	.word 45		; Angle in degrees from +X
-	.word 50		; Power
+	.word 135		; Angle in degrees from +X
+	.word 3		; Power
 	.word 100		; Anger
 	.byte 8,"TINKER   "	; Name
 	.word 0,0,0,0,0,0 ;Padding

projectile.s

@@ -90,16 +90,36 @@ fireProjectile:
 	asl
 	sta projectileData+JD_PRECISEY,y
 
+	lda projectileParams+6		; Convert power to 8.8
+	asl
+	asl
+	asl
+	asl
+	asl
+	asl
+	asl
+	asl
+	sta projectileParams+6
+
 	lda projectileParams+4		; Convert angle to vector
 	asl
 	tax
-	lda angleToVectorX,x		; Velocity X
+	lda angleToVectorX,x		; Velocity X (unit vector)
+
+	sta PARAML1
+	lda projectileParams+6		; Scale by power
+	sta PARAML0
+	jsr mult88
 	sta projectileData+JD_VX,y
 
 	lda projectileParams+4		; Convert angle to vector
 	asl
 	tax
-	lda angleToVectorY,x		; Velocity Y
+	lda angleToVectorY,x		; Velocity Y (unit vector)
+	sta PARAML1
+	lda projectileParams+6		; Scale by power
+	sta PARAML0
+	jsr mult88
 	sta projectileData+JD_VY,y
 
 	RESTORE_AXY

utility.s

@@ -61,6 +61,8 @@ intToStringSkipSingle:
 	sta intToStringResult,y
 	iny
 	inx
+	cpx #3
+	beq intToStringFinish		; Single digit number so we're done
 
 intToStringFullDigitsLoop:
 	; Remaining bytes all contain two digits
@@ -83,6 +85,7 @@ intToStringFullDigitsLoop:
 	cpx #3
 	bne intToStringFullDigitsLoop
 
+intToStringFinish:
 	; Store final length and we're done
 	dey
 	sty intToStringResult
@@ -94,3 +97,58 @@ intToStringDone:
 
 intToStringBCD: .byte 0,0,0
 intToStringResult: .byte 0,0,0,0,0,0
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; mult16
+;
+; PARAML0 = Operand 1 (16 bits)
+; PARAML1 = Operand 2 (16 bits)
+; A => Op1 * Op2 (16 bits)
+; Algorithm from https://apple2.gs/downloads/Programmanual.pdf
+; Trashes X
+;
+mult16:
+	lda #0			; Initialize result
+
+mult16L1:
+	ldx PARAML0		; Get operand 1
+	beq mult16Done	; If operand is zero, we're done
+	lsr PARAML0		; Get low bit
+	bcc mult16L2	; If clear, no additions to previous products
+	clc				; Otherwise add oeprand 2 to partial result
+	adc PARAML1
+
+mult16L2:
+	asl	PARAML1		; Now shift operand 2 left for possible add next time
+	bra mult16L1
+
+mult16Done:
+	rts
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; mult88
+;
+; PARAML0 = Operand 1 (8.8 fixed point)
+; PARAML1 = Operand 2 (8.8 fixed point)
+; A => Op1 * Op2 (8.8 fixed point)
+; Substantial precision loss occurs here, but it's usually good enough
+;
+mult88:
+	lda PARAML0		; Convert operands to 12.4
+	lsr
+	lsr
+	lsr
+	lsr
+	sta PARAML0
+
+	lda PARAML1
+	lsr
+	lsr
+	lsr
+	lsr
+	sta PARAML1
+
+	jsr mult16		; Result is 8.8
+	rts