tida.fps source code

1 /++
2 Module for limiting the release of frames per second.
3 
4 Macros:
5     LREF = <a href="#$1">$1</a>
6     HREF = <a href="$1">$2</a>
7 
8 Authors: $(HREF https://github.com/TodNaz,TodNaz)
9 Copyright: Copyright (c) 2020 - 2021, TodNaz.
10 License: $(HREF https://github.com/TodNaz/Tida/blob/master/LICENSE,MIT)
11 +/
12 module tida.fps;
13 
14 import std.datetime;
15 
16 /++
17 The object that will keep track of the cycle time, counts and
18 limits the executable frames.
19 +/
20 class FPSManager
21 {
22     import core.thread;
23 
24 private:
25     MonoTime controlTime;
26     Duration _deltatime;
27     
28     MonoTime startProgramTime;
29     bool isFirstControl = true;
30     
31     MonoTime lastRenderTime;
32     long countFPS = 0;
33     long resultFPS = 0;
34 
35 public:
36     /++
37     Sets the maximum number of frames per second.
38     +/
39     long maxFPS = 60;
40 
41     /++
42     Shows how many frames were formed in a second.
43     Please note that the counter is updated once per second.
44     +/
45     @property long fps() @safe
46     {
47         return resultFPS;
48     }
49 
50     /++
51     Shows the running time of the program.
52     +/
53     @property Duration timeJobProgram() @safe
54     {
55         return MonoTime.currTime - startProgramTime;
56     }
57 
58     /++
59     Delta time.
60     +/
61     @property Duration deltatime() @safe
62     {
63         return _deltatime;
64     }
65 
66 @trusted:
67     /++
68     The origin of the frame unit. Measures time and also changes the
69     state of the frame counter.
70     +/
71     void countDown()
72     {
73         if (isFirstControl)
74         {
75             isFirstControl = false;
76             startProgramTime = MonoTime.currTime;
77         }
78         
79         if (MonoTime.currTime - lastRenderTime > dur!"msecs"(1000))
80         {
81             resultFPS = countFPS;
82             countFPS = 0;
83             lastRenderTime = MonoTime.currTime;
84         }
85         
86         controlTime = MonoTime.currTime;
87     }
88 
89     /++
90     Frame limiting function. Also, it counts frames per second.
91     +/
92     void control()
93     {
94         countFPS++;
95         
96         immutable timePerFrame = dur!"msecs"(1000) / maxFPS;
97         _deltatime = MonoTime.currTime - controlTime;
98         
99         if (_deltatime < timePerFrame)
100         {
101             Thread.sleep(timePerFrame - _deltatime);
102         }
103     }
104 }