1 /* Copyright 2016-2017 Joaquin M Lopez Munoz.
2 * Distributed under the Boost Software License, Version 1.0.
3 * (See accompanying file LICENSE_1_0.txt or copy at
4 * http://www.boost.org/LICENSE_1_0.txt)
5 *
6 * See http://www.boost.org/libs/poly_collection for library home page.
7 */
8
9 /* segment-specific operations */
10
11 #include <algorithm>
12 #include <boost/poly_collection/any_collection.hpp>
13 #include <boost/poly_collection/base_collection.hpp>
14 #include <boost/type_erasure/operators.hpp>
15 #include <memory>
16 #include <random>
17 #include "rolegame.hpp"
18
operator <<(std::ostream & os,const sprite & s)19 std::ostream& operator<<(std::ostream& os,const sprite& s)
20 {
21 s.render(os);
22 return os;
23 }
24
operator <<(std::ostream & os,const window & w)25 std::ostream& operator<<(std::ostream& os,const window& w)
26 {
27 w.display(os);
28 return os;
29 }
30
main()31 int main()
32 {
33 boost::base_collection<sprite> c;
34
35 //[segmented_structure_1
36 //= std::unique_ptr<sprite> make_sprite()
37 //= {
38 //<-
39 auto make_sprite=[]()->std::unique_ptr<sprite>{
40 //->
41 static std::mt19937 gen{92748};
42 static std::discrete_distribution<> rnd{{1,1,1}};
43 static int id=0;
44
45 switch(rnd(gen)){
46 //<-
47 default:
48 //->
49 case 0: return std::make_unique<warrior>(id++);break;
50 case 1: return std::make_unique<juggernaut>(id++);break;
51 case 2: return std::make_unique<goblin>(id++);break;
52 }
53 //<-
54 };
55 //->
56 //= }
57 //= ...
58 //=
59 //<-
60 try{
61 //->
62 for(int i=0;i<8;++i)c.insert(*make_sprite());
63 // throws boost::poly_collection::unregistered_type
64 //<-
65 }catch(boost::poly_collection::unregistered_type&){}
66 //->
67 //]
68
69 //[segmented_structure_2
70 std::cout<<c.is_registered<warrior>()<<"\n"; // prints 0
71 std::cout<<c.is_registered(typeid(warrior))<<"\n"; // alternate syntax
72 //]
73
74 //[segmented_structure_3
75 c.register_types<warrior,juggernaut,goblin>();
76 // everything works fine now
77 for(int i=0;i<8;++i)c.insert(*make_sprite());
78 //]
79
80 using renderable=boost::type_erasure::ostreamable<>;
81 //[segmented_structure_4
82 boost::any_collection<renderable> c1,c2;
83 //= ... // populate c2
84 //=
85 //<-
86 c2.insert(window{"pop-up"});
87 try{
88 //->
89 c1.insert(*c2.begin()); // throws: actual type of *c2.begin() not known by c1
90 //<-
91 }catch(boost::poly_collection::unregistered_type&){}
92 //->
93 //]
94
95 //[segmented_structure_5
96 //= ... // populate c with 8 assorted entities
97 //=
98 std::cout<<c.size()<<"\n"; // 8 sprites
99 std::cout<<c.size<juggernaut>()<<"\n"; // 2 juggernauts
100 std::cout<<c.size(typeid(juggernaut))<<"\n"; // alternate syntax
101 c.clear<juggernaut>(); // remove juggenauts only
102 std::cout<<c.empty<juggernaut>()<<"\n"; // 1 (no juggernauts left)
103 std::cout<<c.size()<<"\n"; // 6 sprites remaining
104 //]
105
106 //[segmented_structure_6
107 const char* comma="";
108 for(auto first=c.begin(typeid(warrior)),last=c.end(typeid(warrior));
109 first!=last;++first){
110 std::cout<<comma;
111 first->render(std::cout);
112 comma=",";
113 }
114 std::cout<<"\n";
115 //]
116
117 //[segmented_structure_7
118 /*=const char**/ comma="";
119 for(const auto& x:c.segment(typeid(warrior))){
120 std::cout<<comma;
121 x.render(std::cout);
122 comma=",";
123 }
124 std::cout<<"\n";
125 //]
126
127 //[segmented_structure_8
128 /*=const char**/ comma="";
129 for(auto first=c.begin<warrior>(),last=c.end<warrior>();
130 first!=last;++first){
131 first->rank.insert(0,"super");
132 std::cout<<comma;
133 first->render(std::cout);
134 comma=",";
135 }
136 std::cout<<"\n";
137
138 // range-based for loop alternative
139
140 /*=const char**/ comma="";
141 for(auto& x:c.segment<warrior>()){
142 x.rank.insert(0,"super");
143 //<-
144 auto it=x.rank.begin();
145 x.rank.erase(it,it+5); // undo previos op, 5==len("super");
146 //->
147 std::cout<<comma;
148 x.render(std::cout);
149 comma=",";
150 }
151 std::cout<<"\n";
152
153 //]
154
155 auto render=[&](){
156 //[segmented_structure_9
157 const char* comma="";
158 for(auto seg:c.segment_traversal()){
159 for(sprite& s:seg){
160 std::cout<<comma;
161 s.render(std::cout);
162 comma=",";
163 }
164 }
165 std::cout<<"\n";
166 //]
167 };
168 render();
169
170 //[segmented_structure_10
171 c.reserve<goblin>(100); // no reallocation till we exceed 100 goblins
172 std::cout<<c.capacity<goblin>()<<"\n"; // prints 100
173 //]
174
175 //[segmented_structure_11
176 c.reserve(1000); // reserve(1000) for each segment
177 std::cout<<c.capacity<warrior>()<<", "
178 <<c.capacity<juggernaut>()<<", "
179 <<c.capacity<goblin>()<<"\n"; // prints 1000, 1000, 1000
180 //]
181 }
182