gfx/skia/trunk/src/core/SkQuadClipper.cpp@129ffea94266 (annotated)
gfx/skia/trunk/src/core/SkQuadClipper.cpp
Sat, 03 Jan 2015 20:18:00 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Sat, 03 Jan 2015 20:18:00 +0100
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
- permissions
- -rw-r--r--
Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.
| michael@0 | 1 | /* |
| michael@0 | 2 | * Copyright 2009 The Android Open Source Project |
| michael@0 | 3 | * |
| michael@0 | 4 | * Use of this source code is governed by a BSD-style license that can be |
| michael@0 | 5 | * found in the LICENSE file. |
| michael@0 | 6 | */ |
| michael@0 | 7 | |
| michael@0 | 8 | #include "SkQuadClipper.h" |
| michael@0 | 9 | #include "SkGeometry.h" |
| michael@0 | 10 | |
| michael@0 | 11 | SkQuadClipper::SkQuadClipper() { |
| michael@0 | 12 | fClip.setEmpty(); |
| michael@0 | 13 | } |
| michael@0 | 14 | |
| michael@0 | 15 | void SkQuadClipper::setClip(const SkIRect& clip) { |
| michael@0 | 16 | // conver to scalars, since that's where we'll see the points |
| michael@0 | 17 | fClip.set(clip); |
| michael@0 | 18 | } |
| michael@0 | 19 | |
| michael@0 | 20 | /////////////////////////////////////////////////////////////////////////////// |
| michael@0 | 21 | |
| michael@0 | 22 | static bool chopMonoQuadAt(SkScalar c0, SkScalar c1, SkScalar c2, |
| michael@0 | 23 | SkScalar target, SkScalar* t) { |
| michael@0 | 24 | /* Solve F(t) = y where F(t) := [0](1-t)^2 + 2[1]t(1-t) + [2]t^2 |
| michael@0 | 25 | * We solve for t, using quadratic equation, hence we have to rearrange |
| michael@0 | 26 | * our cooefficents to look like At^2 + Bt + C |
| michael@0 | 27 | */ |
| michael@0 | 28 | SkScalar A = c0 - c1 - c1 + c2; |
| michael@0 | 29 | SkScalar B = 2*(c1 - c0); |
| michael@0 | 30 | SkScalar C = c0 - target; |
| michael@0 | 31 | |
| michael@0 | 32 | SkScalar roots[2]; // we only expect one, but make room for 2 for safety |
| michael@0 | 33 | int count = SkFindUnitQuadRoots(A, B, C, roots); |
| michael@0 | 34 | if (count) { |
| michael@0 | 35 | *t = roots[0]; |
| michael@0 | 36 | return true; |
| michael@0 | 37 | } |
| michael@0 | 38 | return false; |
| michael@0 | 39 | } |
| michael@0 | 40 | |
| michael@0 | 41 | static bool chopMonoQuadAtY(SkPoint pts[3], SkScalar y, SkScalar* t) { |
| michael@0 | 42 | return chopMonoQuadAt(pts[0].fY, pts[1].fY, pts[2].fY, y, t); |
| michael@0 | 43 | } |
| michael@0 | 44 | |
| michael@0 | 45 | /////////////////////////////////////////////////////////////////////////////// |
| michael@0 | 46 | |
| michael@0 | 47 | /* If we somehow returned the fact that we had to flip the pts in Y, we could |
| michael@0 | 48 | communicate that to setQuadratic, and then avoid having to flip it back |
| michael@0 | 49 | here (only to have setQuadratic do the flip again) |
| michael@0 | 50 | */ |
| michael@0 | 51 | bool SkQuadClipper::clipQuad(const SkPoint srcPts[3], SkPoint dst[3]) { |
| michael@0 | 52 | bool reverse; |
| michael@0 | 53 | |
| michael@0 | 54 | // we need the data to be monotonically increasing in Y |
| michael@0 | 55 | if (srcPts[0].fY > srcPts[2].fY) { |
| michael@0 | 56 | dst[0] = srcPts[2]; |
| michael@0 | 57 | dst[1] = srcPts[1]; |
| michael@0 | 58 | dst[2] = srcPts[0]; |
| michael@0 | 59 | reverse = true; |
| michael@0 | 60 | } else { |
| michael@0 | 61 | memcpy(dst, srcPts, 3 * sizeof(SkPoint)); |
| michael@0 | 62 | reverse = false; |
| michael@0 | 63 | } |
| michael@0 | 64 | |
| michael@0 | 65 | // are we completely above or below |
| michael@0 | 66 | const SkScalar ctop = fClip.fTop; |
| michael@0 | 67 | const SkScalar cbot = fClip.fBottom; |
| michael@0 | 68 | if (dst[2].fY <= ctop || dst[0].fY >= cbot) { |
| michael@0 | 69 | return false; |
| michael@0 | 70 | } |
| michael@0 | 71 | |
| michael@0 | 72 | SkScalar t; |
| michael@0 | 73 | SkPoint tmp[5]; // for SkChopQuadAt |
| michael@0 | 74 | |
| michael@0 | 75 | // are we partially above |
| michael@0 | 76 | if (dst[0].fY < ctop) { |
| michael@0 | 77 | if (chopMonoQuadAtY(dst, ctop, &t)) { |
| michael@0 | 78 | // take the 2nd chopped quad |
| michael@0 | 79 | SkChopQuadAt(dst, tmp, t); |
| michael@0 | 80 | dst[0] = tmp[2]; |
| michael@0 | 81 | dst[1] = tmp[3]; |
| michael@0 | 82 | } else { |
| michael@0 | 83 | // if chopMonoQuadAtY failed, then we may have hit inexact numerics |
| michael@0 | 84 | // so we just clamp against the top |
| michael@0 | 85 | for (int i = 0; i < 3; i++) { |
| michael@0 | 86 | if (dst[i].fY < ctop) { |
| michael@0 | 87 | dst[i].fY = ctop; |
| michael@0 | 88 | } |
| michael@0 | 89 | } |
| michael@0 | 90 | } |
| michael@0 | 91 | } |
| michael@0 | 92 | |
| michael@0 | 93 | // are we partially below |
| michael@0 | 94 | if (dst[2].fY > cbot) { |
| michael@0 | 95 | if (chopMonoQuadAtY(dst, cbot, &t)) { |
| michael@0 | 96 | SkChopQuadAt(dst, tmp, t); |
| michael@0 | 97 | dst[1] = tmp[1]; |
| michael@0 | 98 | dst[2] = tmp[2]; |
| michael@0 | 99 | } else { |
| michael@0 | 100 | // if chopMonoQuadAtY failed, then we may have hit inexact numerics |
| michael@0 | 101 | // so we just clamp against the bottom |
| michael@0 | 102 | for (int i = 0; i < 3; i++) { |
| michael@0 | 103 | if (dst[i].fY > cbot) { |
| michael@0 | 104 | dst[i].fY = cbot; |
| michael@0 | 105 | } |
| michael@0 | 106 | } |
| michael@0 | 107 | } |
| michael@0 | 108 | } |
| michael@0 | 109 | |
| michael@0 | 110 | if (reverse) { |
| michael@0 | 111 | SkTSwap<SkPoint>(dst[0], dst[2]); |
| michael@0 | 112 | } |
| michael@0 | 113 | return true; |
| michael@0 | 114 | } |
