1 /* 2 * Copyright (C) 2010 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of 14 * its contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #ifndef Distance_h 30 #define Distance_h 31 32 #include "platform/PlatformExport.h" 33 34 namespace blink { 35 36 // Distance models are defined according to the OpenAL specification: 37 // http://connect.creativelabs.com/openal/Documentation/OpenAL%201.1%20Specification.htm. 38 39 class PLATFORM_EXPORT DistanceEffect { 40 public: 41 enum ModelType { 42 ModelLinear = 0, 43 ModelInverse = 1, 44 ModelExponential = 2 45 }; 46 47 DistanceEffect(); 48 49 // Returns scalar gain for the given distance the current distance model is used 50 double gain(double distance); 51 model()52 ModelType model() { return m_model; } 53 setModel(ModelType model,bool clamped)54 void setModel(ModelType model, bool clamped) 55 { 56 m_model = model; 57 m_isClamped = clamped; 58 } 59 60 // Distance params setRefDistance(double refDistance)61 void setRefDistance(double refDistance) { m_refDistance = refDistance; } setMaxDistance(double maxDistance)62 void setMaxDistance(double maxDistance) { m_maxDistance = maxDistance; } setRolloffFactor(double rolloffFactor)63 void setRolloffFactor(double rolloffFactor) { m_rolloffFactor = rolloffFactor; } 64 refDistance()65 double refDistance() const { return m_refDistance; } maxDistance()66 double maxDistance() const { return m_maxDistance; } rolloffFactor()67 double rolloffFactor() const { return m_rolloffFactor; } 68 69 protected: 70 double linearGain(double distance); 71 double inverseGain(double distance); 72 double exponentialGain(double distance); 73 74 ModelType m_model; 75 bool m_isClamped; 76 double m_refDistance; 77 double m_maxDistance; 78 double m_rolloffFactor; 79 }; 80 81 } // namespace blink 82 83 #endif // Distance_h 84