Files
cup_edit/ios/src/camutils/OrbitManipulator.h
2023-10-11 14:12:04 +08:00

202 lines
6.7 KiB
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/*
* Copyright (C) 2020 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef CAMUTILS_ORBIT_MANIPULATOR_H
#define CAMUTILS_ORBIT_MANIPULATOR_H
#include <camutils/Manipulator.h>
#include <math/scalar.h>
#define MAX_PHI (F_PI / 2.0 - 0.001)
namespace filament {
namespace camutils {
using namespace filament::math;
template<typename FLOAT>
class OrbitManipulator : public Manipulator<FLOAT> {
public:
using vec2 = filament::math::vec2<FLOAT>;
using vec3 = filament::math::vec3<FLOAT>;
using vec4 = filament::math::vec4<FLOAT>;
using Bookmark = filament::camutils::Bookmark<FLOAT>;
using Base = Manipulator<FLOAT>;
using Config = typename Base::Config;
enum GrabState { INACTIVE, ORBITING, PANNING };
OrbitManipulator(Mode mode, const Config& props) : Base(mode, props) {
setProperties(props);
Base::mEye = Base::mProps.orbitHomePosition;
mPivot = Base::mTarget = Base::mProps.targetPosition;
}
void setProperties(const Config& props) override {
Config resolved = props;
if (resolved.orbitHomePosition == vec3(0)) {
resolved.orbitHomePosition = vec3(0, 0, 1);
}
if (resolved.orbitSpeed == vec2(0)) {
resolved.orbitSpeed = vec2(0.01);
}
// By default, place the ground plane so that it aligns with the targetPosition position.
// This is used only when PANNING.
if (resolved.groundPlane == vec4(0)) {
const FLOAT d = length(resolved.targetPosition);
const vec3 n = normalize(resolved.orbitHomePosition - resolved.targetPosition);
resolved.groundPlane = vec4(n, -d);
}
Base::setProperties(resolved);
}
void grabBegin(int x, int y, bool strafe) override {
mGrabState = strafe ? PANNING : ORBITING;
mGrabPivot = mPivot;
mGrabEye = Base::mEye;
mGrabTarget = Base::mTarget;
mGrabBookmark = getCurrentBookmark();
mGrabWinX = x;
mGrabWinY = y;
mGrabFar = Base::raycastFarPlane(x, y);
Base::raycast(x, y, &mGrabScene);
}
void grabUpdate(int x, int y) override {
const int delx = mGrabWinX - x;
const int dely = mGrabWinY - y;
if (mGrabState == ORBITING) {
Bookmark bookmark = getCurrentBookmark();
const FLOAT theta = delx * Base::mProps.orbitSpeed.x;
const FLOAT phi = dely * Base::mProps.orbitSpeed.y;
const FLOAT maxPhi = MAX_PHI;
bookmark.orbit.phi = clamp(mGrabBookmark.orbit.phi + phi, -maxPhi, +maxPhi);
bookmark.orbit.theta = mGrabBookmark.orbit.theta + theta;
jumpToBookmark(bookmark);
}
if (mGrabState == PANNING) {
const FLOAT ulen = distance(mGrabScene, mGrabEye);
const FLOAT vlen = distance(mGrabFar, mGrabScene);
const vec3 translation = (mGrabFar - Base::raycastFarPlane(x, y)) * ulen / vlen;
mPivot = mGrabPivot + translation;
Base::mEye = mGrabEye + translation;
Base::mTarget = mGrabTarget + translation;
}
}
void grabEnd() override {
mGrabState = INACTIVE;
}
void scroll(int x, int y, FLOAT scrolldelta) override {
const vec3 gaze = normalize(Base::mTarget - Base::mEye);
const vec3 movement = gaze * Base::mProps.zoomSpeed * -scrolldelta;
const vec3 v0 = mPivot - Base::mEye;
Base::mEye += movement;
Base::mTarget += movement;
const vec3 v1 = mPivot - Base::mEye;
// Check if the camera has moved past the point of interest.
if (dot(v0, v1) < 0) {
mFlipped = !mFlipped;
}
}
Bookmark getCurrentBookmark() const override {
Bookmark bookmark;
bookmark.mode = Mode::ORBIT;
const vec3 pivotToEye = Base::mEye - mPivot;
const FLOAT d = length(pivotToEye);
const FLOAT x = pivotToEye.x / d;
const FLOAT y = pivotToEye.y / d;
const FLOAT z = pivotToEye.z / d;
bookmark.orbit.phi = asin(y);
bookmark.orbit.theta = atan2(x, z);
bookmark.orbit.distance = mFlipped ? -d : d;
bookmark.orbit.pivot = mPivot;
const FLOAT fov = Base::mProps.fovDegrees * math::F_PI / 180.0;
const FLOAT halfExtent = d * tan(fov / 2.0);
const vec3 targetToEye = Base::mProps.groundPlane.xyz;
const vec3 uvec = cross(Base::mProps.upVector, targetToEye);
const vec3 vvec = cross(targetToEye, uvec);
const vec3 centerToTarget = mPivot - Base::mProps.targetPosition;
bookmark.map.extent = halfExtent * 2;
bookmark.map.center.x = dot(uvec, centerToTarget);
bookmark.map.center.y = dot(vvec, centerToTarget);
return bookmark;
}
Bookmark getHomeBookmark() const override {
Bookmark bookmark;
bookmark.mode = Mode::ORBIT;
bookmark.orbit.phi = FLOAT(0);
bookmark.orbit.theta = FLOAT(0);
bookmark.orbit.pivot = Base::mProps.targetPosition;
bookmark.orbit.distance = distance(Base::mProps.targetPosition, Base::mProps.orbitHomePosition);
const FLOAT fov = Base::mProps.fovDegrees * math::F_PI / 180.0;
const FLOAT halfExtent = bookmark.orbit.distance * tan(fov / 2.0);
bookmark.map.extent = halfExtent * 2;
bookmark.map.center.x = 0;
bookmark.map.center.y = 0;
return bookmark;
}
void jumpToBookmark(const Bookmark& bookmark) override {
mPivot = bookmark.orbit.pivot;
const FLOAT x = sin(bookmark.orbit.theta) * cos(bookmark.orbit.phi);
const FLOAT y = sin(bookmark.orbit.phi);
const FLOAT z = cos(bookmark.orbit.theta) * cos(bookmark.orbit.phi);
Base::mEye = mPivot + vec3(x, y, z) * abs(bookmark.orbit.distance);
mFlipped = bookmark.orbit.distance < 0;
Base::mTarget = Base::mEye + vec3(x, y, z) * (mFlipped ? 1.0 : -1.0);
}
private:
GrabState mGrabState = INACTIVE;
bool mFlipped = false;
vec3 mGrabPivot;
vec3 mGrabScene;
vec3 mGrabFar;
vec3 mGrabEye;
vec3 mGrabTarget;
Bookmark mGrabBookmark;
int mGrabWinX;
int mGrabWinY;
vec3 mPivot;
};
} // namespace camutils
} // namespace filament
#endif /* CAMUTILS_ORBIT_MANIPULATOR_H */