camera.h

//
// Copyright 2017 Pixar
//
// Licensed under the Apache License, Version 2.0 (the "Apache License")
// with the following modification; you may not use this file except in
// compliance with the Apache License and the following modification to it:
// Section 6. Trademarks. is deleted and replaced with:
//
// 6. Trademarks. This License does not grant permission to use the trade
//    names, trademarks, service marks, or product names of the Licensor
//    and its affiliates, except as required to comply with Section 4(c) of
//    the License and to reproduce the content of the NOTICE file.
//
// You may obtain a copy of the Apache License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the Apache License with the above modification is
// distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the Apache License for the specific
// language governing permissions and limitations under the Apache License.
//
#ifndef PXR_IMAGING_HD_CAMERA_H
#define PXR_IMAGING_HD_CAMERA_H

#include "pxr/pxr.h"
#include "pxr/imaging/hd/api.h"
#include "pxr/imaging/hd/version.h"
#include "pxr/imaging/hd/sprim.h"

#include "pxr/imaging/cameraUtil/conformWindow.h"

#include "pxr/usd/sdf/path.h"
#include "pxr/base/tf/staticTokens.h"
#include "pxr/base/gf/matrix4d.h"
#include "pxr/base/gf/range1f.h"

#include <vector>

PXR_NAMESPACE_OPEN_SCOPE

#define HD_CAMERA_TOKENS                            \
    /* frustum */                                   \
    (projection)                                    \
    (horizontalAperture)                            \
    (verticalAperture)                              \
    (horizontalApertureOffset)                      \
    (verticalApertureOffset)                        \
    (focalLength)                                   \
    (clippingRange)                                 \
    (clipPlanes)                                    \
                                                    \
    /* depth of field */                            \
    (fStop)                                         \
    (focusDistance)                                 \
                                                    \
    /* shutter/lighting */                          \
    (shutterOpen)                                   \
    (shutterClose)                                  \
    (exposure)                                      \
                                                    \
    /* how to match window with different aspect */ \
    (windowPolicy)                                  \
                                                    \
    /* OpenGL-style matrices, deprecated */         \
    (worldToViewMatrix)                             \
    (projectionMatrix)


TF_DECLARE_PUBLIC_TOKENS(HdCameraTokens, HD_API, HD_CAMERA_TOKENS);

class HdCamera : public HdSprim
{
public:
    using ClipPlanesVector = std::vector<GfVec4d>;

    HD_API
    HdCamera(SdfPath const & id);
    HD_API
    ~HdCamera() override;

    // change tracking for HdCamera
    enum DirtyBits : HdDirtyBits
    {
        Clean                 = 0,
        DirtyTransform        = 1 << 0,
        DirtyViewMatrix       = DirtyTransform, // deprecated
        DirtyProjMatrix       = 1 << 1,         // deprecated
        DirtyWindowPolicy     = 1 << 2,
        DirtyClipPlanes       = 1 << 3,
        DirtyParams           = 1 << 4,
        AllDirty              = (DirtyTransform
                                |DirtyProjMatrix
                                |DirtyWindowPolicy
                                |DirtyClipPlanes
                                |DirtyParams)
    };

    enum Projection {
        Perspective = 0,
        Orthographic
    };

    // ---------------------------------------------------------------------- //
    // ---------------------------------------------------------------------- //
 
    HD_API
    void Sync(HdSceneDelegate *sceneDelegate,
              HdRenderParam   *renderParam,
              HdDirtyBits     *dirtyBits) override;
    

    HD_API
    HdDirtyBits GetInitialDirtyBitsMask() const override;
 
    // ---------------------------------------------------------------------- //
    // ---------------------------------------------------------------------- //

    GfMatrix4d const& GetTransform() const {
        return _transform;
    }

    Projection GetProjection() const {
        return _projection;
    }

    float GetHorizontalAperture() const {
        return _horizontalAperture;
    }

    float GetVerticalAperture() const {
        return _verticalAperture;
    }

    float GetHorizontalApertureOffset() const {
        return _horizontalApertureOffset;
    }

    float GetVerticalApertureOffset() const {
        return _verticalApertureOffset;
    }

    float GetFocalLength() const {
        return _focalLength;
    }

    GfRange1f const &GetClippingRange() const {
        return _clippingRange;
    }
    
    std::vector<GfVec4d> const& GetClipPlanes() const {
        return _clipPlanes;
    }

    float GetFStop() const {
        return _fStop;
    }

    float GetFocusDistance() const {
        return _focusDistance;
    }

    double GetShutterOpen() const {
        return _shutterOpen;
    }

    double GetShutterClose() const {
        return _shutterClose;
    }

    float GetExposure() const {
        return _exposure;
    }

    CameraUtilConformWindowPolicy const& GetWindowPolicy() const {
        return _windowPolicy;
    }

    // ---------------------------------------------------------------------- //
    // ---------------------------------------------------------------------- //

    HD_API
    GfMatrix4d GetViewMatrix() const;

    HD_API
    GfMatrix4d GetViewInverseMatrix() const;

    HD_API
    GfMatrix4d GetProjectionMatrix() const;

protected:
    // frustum
    GfMatrix4d              _transform;
    Projection              _projection;
    float                   _horizontalAperture;
    float                   _verticalAperture;
    float                   _horizontalApertureOffset;
    float                   _verticalApertureOffset;
    float                   _focalLength;
    GfRange1f               _clippingRange;
    std::vector<GfVec4d>    _clipPlanes;

    // focus
    float                   _fStop;
    float                   _focusDistance;

    // shutter/lighting
    double                  _shutterOpen;
    double                  _shutterClose;
    float                   _exposure;

    // Camera's opinion how it display in a window with
    // a different aspect ratio
    CameraUtilConformWindowPolicy _windowPolicy;

    // OpenGL-style matrices
    GfMatrix4d _worldToViewMatrix;
    GfMatrix4d _worldToViewInverseMatrix;
    GfMatrix4d _projectionMatrix;
};

PXR_NAMESPACE_CLOSE_SCOPE

#endif // PXR_IMAGING_HD_CAMERA_H