Routines
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E6C4: Apply Entity Velocity
Used by the routine at Process_Cluster_Entity.
Applies a pre-computed velocity nudge (BC) to the Y and X position bytes of the entity record, clamping each to the play area bounds, and redraws the entity via Draw_Narrow_Entity_Sprite. Called as the contact handler from Process_Cluster_Entity when a cluster entity reaches the player.
Apply_Entity_Velocity E6C4 EXX Switch to alternate registers, save the entity position pointer, and load the Y and X position bytes.
E6C5 LD D,H
E6C6 LD E,L
E6C7 INC DE
E6C8 INC DE
E6C9 INC DE
E6CA INC DE
E6CB LD A,(DE)
E6CC ADD A,(HL)
E6CD CP $10 Test and apply the Y nudge; clamp Y to 10-B3 and write back.
E6CF JP C,Apply_Entity_Velocity_X
E6D2 CP $B3
E6D4 JP NC,Apply_Entity_Velocity_X
E6D7 LD (HL),A
Apply_Entity_Velocity_X E6D8 INC HL Test and apply the X nudge; clamp X to 08-F3 and write back.
E6D9 INC DE
E6DA LD A,(DE)
E6DB ADD A,(HL)
E6DC CP $08
E6DE JP C,Apply_Entity_Velocity_Draw
E6E1 CP $F3
E6E3 JP NC,Apply_Entity_Velocity_Draw
E6E6 LD (HL),A
Apply_Entity_Velocity_Draw E6E7 DEC HL Step back two bytes, set colour INK: WHITE, PAPER: BLACK (BRIGHT) in B', and draw the entity via Draw_Narrow_Entity_Sprite.
E6E8 DEC HL
E6E9 PUSH DE
E6EA EXX
E6EB LD B,$47
E6ED EXX
E6EE CALL Draw_Narrow_Entity_Sprite Restore DE, copy to HL, advance two bytes, and return.
E6F1 POP DE
E6F2 LD H,D
E6F3 LD L,E
E6F4 INC HL
E6F5 INC HL
E6F6 RET
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