SkPathRef.cpp File Reference

#include "include/private/SkPathRef.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkPath.h"
#include "include/core/SkRRect.h"
#include "include/private/base/SkFloatingPoint.h"
#include "include/private/base/SkOnce.h"
#include "src/base/SkVx.h"
#include <cstring>

Go to the source code of this file.

Functions
static void	transform_dir_and_start (const SkMatrix &matrix, bool isRRect, bool *isCCW, unsigned *start)

Variables
static constexpr int	kPathRefGenIDBitCnt = 32
static SkPathRef *	gEmpty = nullptr

Function Documentation

transform_dir_and_start()

static void transform_dir_and_start ( const SkMatrix &  matrix, bool  isRRect, bool *  isCCW, unsigned *  start  )

static

Definition at line 85 of file SkPathRef.cpp.

                                                     {
    int inStart = *start;
    int rm = 0;
    if (isRRect) {
        // Degenerate rrect indices to oval indices and remember the remainder.
        // Ovals have one index per side whereas rrects have two.
        rm = inStart & 0b1;
        inStart /= 2;
    }
    // Is the antidiagonal non-zero (otherwise the diagonal is zero)
    int antiDiag;
    // Is the non-zero value in the top row (either kMScaleX or kMSkewX) negative
    int topNeg;
    // Are the two non-zero diagonal or antidiagonal values the same sign.
    int sameSign;
    if (matrix.get(SkMatrix::kMScaleX) != 0) {
        antiDiag = 0b00;
        if (matrix.get(SkMatrix::kMScaleX) > 0) {
            topNeg = 0b00;
            sameSign = matrix.get(SkMatrix::kMScaleY) > 0 ? 0b01 : 0b00;
        } else {
            topNeg = 0b10;
            sameSign = matrix.get(SkMatrix::kMScaleY) > 0 ? 0b00 : 0b01;
        }
    } else {
        antiDiag = 0b01;
        if (matrix.get(SkMatrix::kMSkewX) > 0) {
            topNeg = 0b00;
            sameSign = matrix.get(SkMatrix::kMSkewY) > 0 ? 0b01 : 0b00;
        } else {
            topNeg = 0b10;
            sameSign = matrix.get(SkMatrix::kMSkewY) > 0 ? 0b00 : 0b01;
        }
    }
    if (sameSign != antiDiag) {
        // This is a rotation (and maybe scale). The direction is unchanged.
        // Trust me on the start computation (or draw yourself some pictures)
        *start = (inStart + 4 - (topNeg | antiDiag)) % 4;
        SkASSERT(*start < 4);
        if (isRRect) {
            *start = 2 * *start + rm;
        }
    } else {
        // This is a mirror (and maybe scale). The direction is reversed.
        *isCCW = !*isCCW;
        // Trust me on the start computation (or draw yourself some pictures)
        *start = (6 + (topNeg | antiDiag) - inStart) % 4;
        SkASSERT(*start < 4);
        if (isRRect) {
            *start = 2 * *start + (rm ? 0 : 1);
        }
    }
}

Variable Documentation

gEmpty

SkPathRef* gEmpty = nullptr

static

Definition at line 74 of file SkPathRef.cpp.

kPathRefGenIDBitCnt

constexpr int kPathRefGenIDBitCnt = 32

staticconstexpr

Definition at line 22 of file SkPathRef.cpp.