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/*
* Copyright 2010, Google Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
// Cubic curve classification algorithm from "Rendering Vector Art on
// the GPU" by Loop and Blinn, GPU Gems 3, Chapter 25.
#ifndef O3D_CORE_CROSS_GPU2D_CUBIC_CLASSIFIER_H_
#define O3D_CORE_CROSS_GPU2D_CUBIC_CLASSIFIER_H_
#include "base/basictypes.h"
namespace o3d {
namespace gpu2d {
// Classifies cubic curves into specific types.
class CubicClassifier {
public:
// The types of cubic curves.
enum CurveType {
kSerpentine,
kCusp,
kLoop,
kQuadratic,
kLine,
kPoint
};
// The result of the classifier.
class Result {
public:
Result(CurveType curve_type,
float d1, float d2, float d3)
: curve_type_(curve_type),
d1_(d1),
d2_(d2),
d3_(d3) {
}
CurveType curve_type() const {
return curve_type_;
}
float d1() const {
return d1_;
}
float d2() const {
return d2_;
}
float d3() const {
return d3_;
}
private:
CurveType curve_type_;
float d1_;
float d2_;
float d3_;
};
// Classifies the given cubic bezier curve starting at (b0x, b0y),
// ending at (b3x, b3y), and affected by control points (b1x, b1y)
// and (b2x, b2y).
static Result Classify(float b0x, float b0y,
float b1x, float b1y,
float b2x, float b2y,
float b3x, float b3y);
private:
// This class does not need to be instantiated.
CubicClassifier() {}
DISALLOW_COPY_AND_ASSIGN(CubicClassifier);
};
} // namespace gpu2d
} // namespace o3d
#endif // O3D_CORE_CROSS_GPU2D_CUBIC_CLASSIFIER_H_
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