SkCamera3D Class Reference

#include <SkCamera.h>

Public Member Functions
	SkCamera3D ()
void	reset ()
void	update ()
void	patchToMatrix (const SkPatch3D &, SkMatrix *matrix) const

Public Attributes
SkV3	fLocation
SkV3	fAxis
SkV3	fZenith
SkV3	fObserver

Detailed Description

Definition at line 53 of file SkCamera.h.

Constructor & Destructor Documentation

SkCamera3D()

SkCamera3D::SkCamera3D

(

)

Definition at line 54 of file SkCamera.cpp.

                       {
    this->reset();
}

Member Function Documentation

patchToMatrix()

void SkCamera3D::patchToMatrix	(	const SkPatch3D &	quilt,
		SkMatrix *	matrix
	)		const

Definition at line 113 of file SkCamera.cpp.

                                                                             {
    if (fNeedToUpdate) {
        this->doUpdate();
        fNeedToUpdate = false;
    }
 
    const SkScalar* mapPtr = (const SkScalar*)(const void*)&fOrientation;
    const SkScalar* patchPtr;
 
    SkV3 diff = quilt.fOrigin - fLocation;
    SkScalar dot = diff.dot({mapPtr[6], mapPtr[7], mapPtr[8]});
 
    // This multiplies fOrientation by the matrix [quilt.fU quilt.fV diff] -- U, V, and diff are
    // column vectors in the matrix -- then divides by the length of the projection of diff onto
    // the view axis (which is 'dot'). This transforms the patch (which transforms from local path
    // space to world space) into view space (since fOrientation transforms from world space to
    // view space).
    //
    // The divide by 'dot' isn't strictly necessary as the homogeneous divide would do much the
    // same thing (it's just scaling the entire matrix by 1/dot). It looks like it's normalizing
    // the matrix into some canonical space.
    patchPtr = (const SkScalar*)&quilt;
    matrix->set(SkMatrix::kMScaleX, SkScalarDotDiv(3, patchPtr, 1, mapPtr, 1, dot));
    matrix->set(SkMatrix::kMSkewY,  SkScalarDotDiv(3, patchPtr, 1, mapPtr+3, 1, dot));
    matrix->set(SkMatrix::kMPersp0, SkScalarDotDiv(3, patchPtr, 1, mapPtr+6, 1, dot));
 
    patchPtr += 3;
    matrix->set(SkMatrix::kMSkewX,  SkScalarDotDiv(3, patchPtr, 1, mapPtr, 1, dot));
    matrix->set(SkMatrix::kMScaleY, SkScalarDotDiv(3, patchPtr, 1, mapPtr+3, 1, dot));
    matrix->set(SkMatrix::kMPersp1, SkScalarDotDiv(3, patchPtr, 1, mapPtr+6, 1, dot));
 
    patchPtr = (const SkScalar*)(const void*)&diff;
    matrix->set(SkMatrix::kMTransX, SkScalarDotDiv(3, patchPtr, 1, mapPtr, 1, dot));
    matrix->set(SkMatrix::kMTransY, SkScalarDotDiv(3, patchPtr, 1, mapPtr+3, 1, dot));
    matrix->set(SkMatrix::kMPersp2, SK_Scalar1);
}

reset()

void SkCamera3D::reset

(

)

Definition at line 58 of file SkCamera.cpp.

                       {
    fLocation = {0, 0, -SkIntToScalar(576)};   // 8 inches backward
    fAxis = {0, 0, SK_Scalar1};                // forward
    fZenith = {0, -SK_Scalar1, 0};             // up
 
    fObserver = {0, 0, fLocation.z};
 
    fNeedToUpdate = true;
}

update()

void SkCamera3D::update

(

)

Definition at line 68 of file SkCamera.cpp.

                        {
    fNeedToUpdate = true;
}

Member Data Documentation

fAxis

SkV3 SkCamera3D::fAxis

Definition at line 62 of file SkCamera.h.

fLocation

SkV3 SkCamera3D::fLocation

Definition at line 61 of file SkCamera.h.

fObserver

SkV3 SkCamera3D::fObserver

Definition at line 64 of file SkCamera.h.

fZenith

SkV3 SkCamera3D::fZenith

Definition at line 63 of file SkCamera.h.

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The documentation for this class was generated from the following files:

• third_party/skia/include/utils/SkCamera.h
• third_party/skia/src/utils/SkCamera.cpp