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Routines |
| Prev: 55088 | Up: Map | Next: 55283 |
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Checking if:
Only one creature missile and one Maroc-fired missile (i.e. 2 missiles total) can be on-screen at any one time.
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| 55188 | LD A,0 | |||
| 55190 | LD (60116),A | Indicates screen/viewport - 0 = current screen/viewport | ||
| 55193 | LD A,5 | |||
| 55195 | LD (60314),A | Pre-set the missile type. 5 = missile fired at Maroc by creatures (rather than vice versa) | ||
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Check if a missile/bolt has been set up (and if not, set it up):
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| 55198 | LD A,(60307) | Get missile number (table at 27868) | ||
| 55201 | CP 0 | |||
| 55203 | JR Z,55213 | 0 = no missile present | ||
| 55205 | CALL 56095 | If not zero, set up this missile set data | ||
| 55208 | LD A,0 | Missile has now been set up and stored in the data sets at 31744, so can now set the missile number to zero | ||
| 55210 | LD (60307),A | |||
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Check if Maroc has launched a missile spell:
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| 55213 | LD A,(60568) | This byte contains an 'action' byte set when Maroc presses fire after aiming his missile-based spell cursor, and contains values for the different missile spells | ||
| 55216 | CP 0 | If zero, Maroc hasn't fired a missile spell - skip next section | ||
| 55218 | JR Z,55283 | |||
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Maroc has launched a missile-type spell. Calculate trajectory of missile:
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| 55220 | LD A,(60306) | Flag indicating if Maroc has fired a missile (1 = missile fired, 0 = no missile) | ||
| 55223 | CP 0 | |||
| 55225 | JR NZ,55278 | If there's already one, skip the setup | ||
| 55227 | INC A | Increment so the flag = 1 (missile fired) | ||
| 55228 | LD (60306),A | ...and re-store. | ||
| 55231 | LD A,0 | Precision/overflow byte for horizontal/vertical item position (reset both to 0) | ||
| 55233 | LD (60308),A | |||
| 55236 | LD (60310),A | |||
| 55239 | LD A,(60096) | Maroc's horizontal (X-axis) screen position | ||
| 55242 | LD (60309),A | Set this as the missile's horizontal (X) co-ordinate origin | ||
| 55245 | LD A,(60097) | Maroc's vertical (Y-axis) screen position | ||
| 55248 | LD (60311),A | Set this as the missile's vertical (Y) co-ordinate origin | ||
| 55251 | LD A,(60159) | Get the vertical (Y) pixel position of the aiming cursor | ||
| 55254 | LD (60313),A | Store as the target vertical pixel (Y) co-ordinate for the missile | ||
| 55257 | LD A,(60160) | Get the horizontal (X) pixel position of the aiming cursor | ||
| 55260 | RRA | This value is currently in pixel steps, so divide by 4 to get into 4-pixel (half-character steps) | ||
| 55261 | RRA | |||
| 55262 | AND 63 | Filter out any unnecessary carry bits | ||
| 55264 | LD (60312),A | ...and store | ||
| 55267 | LD A,8 | Item/missile type = 8 (missile fired by Maroc) | ||
| 55269 | LD (60314),A | Store in missile data set | ||
| 55272 | LD A,(60568) | |||
| 55275 | CALL 56095 | Set up missile data | ||
| 55278 | LD A,0 | This is the action byte set when Maroc presses fire after aiming his missile-based spell cursor - contains values for the different missile spells | ||
| 55280 | LD (60568),A | Now that the missile has been initialized, set this flag to 0. | ||
| Prev: 55088 | Up: Map | Next: 55283 |