/* ============================================================================== This file is part of the JUCE library. Copyright (c) 2017 - ROLI Ltd. JUCE is an open source library subject to commercial or open-source licensing. By using JUCE, you agree to the terms of both the JUCE 5 End-User License Agreement and JUCE 5 Privacy Policy (both updated and effective as of the 27th April 2017). End User License Agreement: www.juce.com/juce-5-licence Privacy Policy: www.juce.com/juce-5-privacy-policy Or: You may also use this code under the terms of the GPL v3 (see www.gnu.org/licenses). JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE DISCLAIMED. ============================================================================== */ #pragma once //============================================================================== /** Stores a 3D orientation, which can be rotated by dragging with the mouse. */ class Draggable3DOrientation { public: typedef Vector3D VectorType; typedef Quaternion QuaternionType; /** Creates a Draggable3DOrientation, initially set up to be aligned along the X axis. */ Draggable3DOrientation (float objectRadius = 0.5f) noexcept : radius (jmax (0.1f, objectRadius)), quaternion (VectorType::xAxis(), 0) { } /** Creates a Draggable3DOrientation from a user-supplied quaternion. */ Draggable3DOrientation (const Quaternion& quaternionToUse, float objectRadius = 0.5f) noexcept : radius (jmax (0.1f, objectRadius)), quaternion (quaternionToUse) { } /** Resets the orientation, specifying the axis to align it along. */ void reset (const VectorType& axis) noexcept { quaternion = QuaternionType (axis, 0); } /** Sets the viewport area within which mouse-drag positions will occur. You'll need to set this rectangle before calling mouseDown. The centre of the rectangle is assumed to be the centre of the object that will be rotated, and the size of the rectangle will be used to scale the object radius - see setRadius(). */ void setViewport (const Rectangle& newArea) noexcept { area = newArea; } /** Sets the size of the rotated object, as a proportion of the viewport's size. @see setViewport */ void setRadius (float newRadius) noexcept { radius = jmax (0.1f, newRadius); } /** Begins a mouse-drag operation. You must call this before any calls to mouseDrag(). The position that is supplied will be treated as being relative to the centre of the rectangle passed to setViewport(). */ template void mouseDown (Point mousePos) noexcept { lastMouse = mousePosToProportion (mousePos.toFloat()); } /** Continues a mouse-drag operation. After calling mouseDown() to begin a drag sequence, you can call this method to continue it. */ template void mouseDrag (Point mousePos) noexcept { const VectorType oldPos (projectOnSphere (lastMouse)); lastMouse = mousePosToProportion (mousePos.toFloat()); const VectorType newPos (projectOnSphere (lastMouse)); quaternion *= rotationFromMove (oldPos, newPos); } /** Returns the matrix that should be used to apply the current orientation. @see applyToOpenGLMatrix */ Matrix3D getRotationMatrix() const noexcept { return quaternion.getRotationMatrix(); } /** Provides direct access to the quaternion. */ QuaternionType& getQuaternion() noexcept { return quaternion; } private: Rectangle area; float radius; QuaternionType quaternion; Point lastMouse; Point mousePosToProportion (const Point mousePos) const noexcept { const int scale = (jmin (area.getWidth(), area.getHeight()) / 2); // You must call setViewport() to give this object a valid window size before // calling any of the mouse input methods! jassert (scale > 0); return Point ((mousePos.x - area.getCentreX()) / scale, (area.getCentreY() - mousePos.y) / scale); } VectorType projectOnSphere (const Point pos) const noexcept { const float radiusSquared = radius * radius; const float xySquared = pos.x * pos.x + pos.y * pos.y; return VectorType (pos.x, pos.y, xySquared < radiusSquared * 0.5f ? std::sqrt (radiusSquared - xySquared) : (radiusSquared / (2.0f * std::sqrt (xySquared)))); } QuaternionType rotationFromMove (const VectorType& from, const VectorType& to) const noexcept { VectorType rotationAxis (to ^ from); if (rotationAxis.lengthIsBelowEpsilon()) rotationAxis = VectorType::xAxis(); const float d = jlimit (-1.0f, 1.0f, (from - to).length() / (2.0f * radius)); return QuaternionType::fromAngle (2.0f * std::asin (d), rotationAxis); } };