AceSegment  0.3.0
An adjustable, configurable, and extensible framework for rendering seven segment LED displays.
PulseStyler.h
1 /*
2 MIT License
3 
4 Copyright (c) 2018 Brian T. Park
5 
6 Permission is hereby granted, free of charge, to any person obtaining a copy
7 of this software and associated documentation files (the "Software"), to deal
8 in the Software without restriction, including without limitation the rights
9 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 copies of the Software, and to permit persons to whom the Software is
11 furnished to do so, subject to the following conditions:
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13 The above copyright notice and this permission notice shall be included in all
14 copies or substantial portions of the Software.
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16 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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20 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 SOFTWARE.
23 */
24 
25 #ifndef ACE_SEGMENT_PULSE_STYLER_H
26 #define ACE_SEGMENT_PULSE_STYLER_H
27 
28 #include <stdint.h>
29 #include "Styler.h"
30 
31 namespace ace_segment {
32 
33 class PulseStyler: public Styler {
34  public:
35  PulseStyler(uint8_t framesPerSecond, uint16_t durationMillis):
36  mFramesPerPulse((uint32_t) framesPerSecond * durationMillis / 1000),
37  mFramesPerPulseInverse((uint32_t) 65536 * 1000
38  / framesPerSecond / durationMillis)
39  {}
40 
41  virtual void calcForFrame() override {
42  uint16_t middleOfPulse = mFramesPerPulse / 2;
43 
44  uint16_t fraction;
45  if (mCurrentFrame < middleOfPulse) {
46  fraction = (uint32_t) mFramesPerPulseInverse * mCurrentFrame / (256/2);
47  } else if (mCurrentFrame < mFramesPerPulse) {
48  uint16_t reverse = (mFramesPerPulse - mCurrentFrame - 1);
49  fraction = (uint32_t) mFramesPerPulseInverse * reverse / (256/2);
50  } else {
51  fraction = 0;
52  }
53  if (fraction > 255) fraction = 255;
54 
55  mPulseFraction = fraction;
56  Util::incrementMod(mCurrentFrame, mFramesPerPulse);
57  }
58 
59  virtual void apply(uint8_t* pattern, uint8_t* brightness) override {
60  *brightness = ((uint16_t) mPulseFraction * (*brightness)) / 256;
61  }
62 
63  virtual bool requiresBrightness() override { return true; }
64 
65  private:
66  const uint16_t mFramesPerPulse;
67  const uint16_t mFramesPerPulseInverse; // 65536/mFramesPerPulse
68  uint16_t mCurrentFrame = 0;
69  uint8_t mPulseFraction;
70 };
71 
72 }
73 
74 #endif
virtual bool requiresBrightness() override
Requires driver support for brightness control if true.
Definition: PulseStyler.h:63
virtual void calcForFrame() override
Called once per frame to update the internal variables of the object.
Definition: PulseStyler.h:41
Interface for classes which apply a style to the given bit pattern and brightness.
Definition: Styler.h:34
static void incrementMod(T &i, T m)
Increment i modulo m, avoiding expensive % operator on some 8-bit processors like AVR...
Definition: Util.h:39
virtual void apply(uint8_t *pattern, uint8_t *brightness) override
Changes updates the brightness for current frame.
Definition: PulseStyler.h:59