Routines
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46392: Test Object Solid
Used by the routines at TestObjectIntersections, BlockMovementInX, BlockMovementInY and BlockMovementInZ.
Tests whether the object that IY points at is present and is not flagged to be ignored in the 3D calculations. The zero flag is set if the slot is unused or bit 1 of the flags is set.
Input
IY The address of the object
Output
F Zero flag set if the slot is not used or the object is ignored
Return if the slot is empty.
TestObjectSolid 46392 LD A,(IY+0) Fetch the graphic number of the object.
Test it, as zero means that there is no object.
46395 AND A Return if the slot is not used.
46396 RET Z
After invert, bit 1 is set when the object is not ignored.
46397 LD A,(IY+7) Fetch the flags of the object.
46400 CPL Invert them.
46401 AND %00000010 Keep the ignore flag, which is now clear if the object is ignored.
46403 RET Return.
View the equivalent code in;
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