crawl-ref/source/losparam.h

   1 /*
   2  *  File:       losparam.h
   3  *  Summary:    Parameters for the LOS algorithm
   4  */
   5
   6 #ifndef LOSPARAM_H
   7 #define LOSPARAM_H
   8
   9 // Note: find_ray relies on the fact that 2*OPC_HALF == OPC_OPAQUE.
  10 // On the other hand, losight tracks this explicitly.
  11 enum opacity_type
  12 {
  13     OPC_CLEAR  = 0,
  14     OPC_HALF   = 1,    // for opaque clouds; two or more block
  15     OPC_OPAQUE = 2,
  16
  17     NUM_OPACITIES
  18 };
  19
  20 class opacity_func
  21 {
  22 public:
  23     virtual opacity_type operator()(const coord_def& p) const = 0;
  24     virtual ~opacity_func() {}
  25     virtual opacity_func* clone() const = 0;
  26 };
  27
  28 #define CLONE(typename) \
  29     typename* clone() const \
  30     { \
  31         return (new typename(*this)); \
  32     }
  33
  34 // Default LOS rules.
  35 class opacity_default : public opacity_func
  36 {
  37 public:
  38     CLONE(opacity_default)
  39
  40     opacity_type operator()(const coord_def& p) const;
  41 };
  42 static opacity_default opc_default;
  43
  44 // Default LOS rules, but only consider fully opaque features blocking.
  45 // In particular, clouds don't affect the result.
  46 class opacity_fullyopaque : public opacity_func
  47 {
  48 public:
  49     CLONE(opacity_fullyopaque)
  50
  51     opacity_type operator()(const coord_def& p) const;
  52 };
  53 static opacity_fullyopaque opc_fullyopaque;
  54
  55 // Make transparent features block in addition to normal LOS.
  56 // * Translocations opacity: blink, apportation, portal projectile.
  57 // * Various "I feel safe"-related stuff.
  58 class opacity_no_trans : public opacity_func
  59 {
  60 public:
  61     CLONE(opacity_no_trans)
  62
  63     opacity_type operator()(const coord_def& p) const;
  64 };
  65 static opacity_no_trans opc_no_trans;
  66
  67 // Make immobile monsters block in addition to no_trans.
  68 // This is used for monster movement.
  69 class opacity_immob : public opacity_func
  70 {
  71 public:
  72     CLONE(opacity_immob)
  73
  74     opacity_type operator()(const coord_def& p) const;
  75 };
  76 static opacity_immob opc_immob;
  77
  78 // Make anything solid block in addition to normal LOS.
  79 class opacity_solid : public opacity_func
  80 {
  81 public:
  82     CLONE(opacity_solid)
  83
  84     opacity_type operator()(const coord_def& p) const;
  85 };
  86 static opacity_solid opc_solid;
  87
  88 // Opacity for monster movement, based on the late monster_los.
  89 class opacity_monmove : public opacity_func
  90 {
  91 public:
  92     opacity_monmove(const monster& m)
  93         : mon(m)
  94     {
  95     }
  96
  97     CLONE(opacity_monmove)
  98
  99     opacity_type operator()(const coord_def& p) const;
 100 private:
 101     const monster& mon;
 102 };
 103
 104 // Make any actor (as well as solid features) block.
 105 // Note that the blocking actors are still "visible".
 106 class opacity_no_actor : public opacity_func
 107 {
 108 public:
 109     CLONE(opacity_no_actor)
 110
 111     opacity_type operator()(const coord_def& p) const;
 112 };
 113 static opacity_no_actor opc_no_actor;
 114
 115 // Subclasses of this are passed to losight() to modify the
 116 // LOS calculation. Implementations will have to translate between
 117 // relative coordinates (-8,-8)..(8,8) and real coordinates,
 118 // specify how opaque the cells are and determine what values
 119 // are written to the visible cells.
 120 class los_param
 121 {
 122 public:
 123     virtual ~los_param() {}
 124
 125     // Whether the translated coordinate lies within the map
 126     // (including boundary) and within the LOS area
 127     virtual bool los_bounds(const coord_def& p) const = 0;
 128
 129     virtual opacity_type opacity(const coord_def& p) const = 0;
 130 };
 131
 132 #endif