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⌂ ∞ ▽ Elite on the 6502

Drawing ships: SHIP_SPLINTER

[NES version, Bank 1]

       Name: SHIP_SPLINTER                                           [Show more]
       Type: Variable
   Category: Drawing ships
    Summary: Ship blueprint for a splinter
  Deep dive: Ship blueprints

    Context: See this variable in context in the source code
 References: This variable is used as follows:
             * Unused copy of XX21 uses SHIP_SPLINTER
             * XX21 uses SHIP_SPLINTER




 The ship blueprint for the splinter reuses the edges data from the escape pod,
 so the edges data offset is negative.



.SHIP_SPLINTER

 EQUB 0 + (11 << 4)     ; Max. canisters on demise = 0
                        ; Market item when scooped = 11 + 1 = 12 (Minerals)
 EQUW 16 * 16           ; Targetable area          = 16 * 16

 EQUB LO(SHIP_ESCAPE_POD_EDGES - SHIP_SPLINTER)    ; Edges from escape pod
 EQUB LO(SHIP_SPLINTER_FACES - SHIP_SPLINTER) + 24 ; Faces data offset (low)

 EQUB 29                ; Max. edge count          = (29 - 1) / 4 = 7
 EQUB 0                 ; Gun vertex               = 0
 EQUB 22                ; Explosion count          = 4, as (4 * n) + 6 = 22
 EQUB 24                ; Number of vertices       = 24 / 6 = 4
 EQUB 6                 ; Number of edges          = 6
 EQUW 0                 ; Bounty                   = 0
 EQUB 16                ; Number of faces          = 16 / 4 = 4
 EQUB 8                 ; Visibility distance      = 8
 EQUB 20                ; Max. energy              = 20
 EQUB 10                ; Max. speed               = 10

 EQUB HI(SHIP_ESCAPE_POD_EDGES - SHIP_SPLINTER)    ; Edges from escape pod
 EQUB HI(SHIP_SPLINTER_FACES - SHIP_SPLINTER)      ; Faces data offset (low)

 EQUB 5                 ; Normals are scaled by    = 2^5 = 32
 EQUB %00000000         ; Laser power              = 0
                        ; Missiles                 = 0

.SHIP_SPLINTER_VERTICES

      ;    x,    y,    z, face1, face2, face3, face4, visibility
 VERTEX  -24,  -25,   16,     2,      1,    3,     3,         31    ; Vertex 0
 VERTEX    0,   12,  -10,     2,      0,    3,     3,         31    ; Vertex 1
 VERTEX   11,   -6,    2,     1,      0,    3,     3,         31    ; Vertex 2
 VERTEX   12,   42,    7,     1,      0,    2,     2,         31    ; Vertex 3

.SHIP_SPLINTER_FACES

    ; normal_x, normal_y, normal_z, visibility
 FACE       35,        0,        4,         31      ; Face 0
 FACE        3,        4,        8,         31      ; Face 1
 FACE        1,        8,       12,         31      ; Face 2
 FACE       18,       12,        0,         31      ; Face 3