| /* |
| * Copyright 2018 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "GrQuad.h" |
| |
| #include "GrTypesPriv.h" |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| // Functions for identifying the quad type from its coordinates, which are kept debug-only since |
| // production code should rely on the matrix to derive the quad type more efficiently. These are |
| // useful in asserts that the quad type is as expected. |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| #ifdef SK_DEBUG |
| // Allow some tolerance from floating point matrix transformations, but SkScalarNearlyEqual doesn't |
| // support comparing infinity, and coords_form_rect should return true for infinite edges |
| #define NEARLY_EQUAL(f1, f2) (f1 == f2 || SkScalarNearlyEqual(f1, f2, 1e-5f)) |
| // Similarly, support infinite rectangles by looking at the sign of infinities |
| static bool dot_nearly_zero(const SkVector& e1, const SkVector& e2) { |
| static constexpr auto dot = SkPoint::DotProduct; |
| static constexpr auto sign = SkScalarSignAsScalar; |
| |
| SkScalar dotValue = dot(e1, e2); |
| if (SkScalarIsNaN(dotValue)) { |
| // Form vectors from the signs of infinities, and check their dot product |
| dotValue = dot({sign(e1.fX), sign(e1.fY)}, {sign(e2.fX), sign(e2.fY)}); |
| } |
| |
| return SkScalarNearlyZero(dotValue, 1e-3f); |
| } |
| |
| // This is not the most performance critical function; code using GrQuad should rely on the faster |
| // quad type from matrix path, so this will only be called as part of SkASSERT. |
| static bool coords_form_rect(const float xs[4], const float ys[4]) { |
| return (NEARLY_EQUAL(xs[0], xs[1]) && NEARLY_EQUAL(xs[2], xs[3]) && |
| NEARLY_EQUAL(ys[0], ys[2]) && NEARLY_EQUAL(ys[1], ys[3])) || |
| (NEARLY_EQUAL(xs[0], xs[2]) && NEARLY_EQUAL(xs[1], xs[3]) && |
| NEARLY_EQUAL(ys[0], ys[1]) && NEARLY_EQUAL(ys[2], ys[3])); |
| } |
| |
| static bool coords_rectilinear(const float xs[4], const float ys[4]) { |
| SkVector e0{xs[1] - xs[0], ys[1] - ys[0]}; // connects to e1 and e2(repeat) |
| SkVector e1{xs[3] - xs[1], ys[3] - ys[1]}; // connects to e0(repeat) and e3 |
| SkVector e2{xs[0] - xs[2], ys[0] - ys[2]}; // connects to e0 and e3(repeat) |
| SkVector e3{xs[2] - xs[3], ys[2] - ys[3]}; // connects to e1(repeat) and e2 |
| |
| e0.normalize(); |
| e1.normalize(); |
| e2.normalize(); |
| e3.normalize(); |
| |
| return dot_nearly_zero(e0, e1) && dot_nearly_zero(e1, e3) && |
| dot_nearly_zero(e2, e0) && dot_nearly_zero(e3, e2); |
| } |
| |
| GrQuadType GrQuad::quadType() const { |
| // Since GrQuad applies any perspective information at construction time, there's only two |
| // types to choose from. |
| if (coords_form_rect(fX, fY)) { |
| return GrQuadType::kRect; |
| } else if (coords_rectilinear(fX, fY)) { |
| return GrQuadType::kRectilinear; |
| } else { |
| return GrQuadType::kStandard; |
| } |
| } |
| |
| GrQuadType GrPerspQuad::quadType() const { |
| if (this->hasPerspective()) { |
| return GrQuadType::kPerspective; |
| } else { |
| // Rect or standard quad, can ignore w since they are all ones |
| if (coords_form_rect(fX, fY)) { |
| return GrQuadType::kRect; |
| } else if (coords_rectilinear(fX, fY)) { |
| return GrQuadType::kRectilinear; |
| } else { |
| return GrQuadType::kStandard; |
| } |
| } |
| } |
| #endif |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| static bool aa_affects_rect(float ql, float qt, float qr, float qb) { |
| return !SkScalarIsInt(ql) || !SkScalarIsInt(qr) || !SkScalarIsInt(qt) || !SkScalarIsInt(qb); |
| } |
| |
| static void map_rect_translate_scale(const SkRect& rect, const SkMatrix& m, |
| Sk4f* xs, Sk4f* ys) { |
| SkMatrix::TypeMask tm = m.getType(); |
| SkASSERT(tm <= (SkMatrix::kScale_Mask | SkMatrix::kTranslate_Mask)); |
| |
| Sk4f r = Sk4f::Load(&rect); |
| if (tm > SkMatrix::kIdentity_Mask) { |
| const Sk4f t(m.getTranslateX(), m.getTranslateY(), m.getTranslateX(), m.getTranslateY()); |
| if (tm <= SkMatrix::kTranslate_Mask) { |
| r += t; |
| } else { |
| const Sk4f s(m.getScaleX(), m.getScaleY(), m.getScaleX(), m.getScaleY()); |
| r = r * s + t; |
| } |
| } |
| *xs = SkNx_shuffle<0, 0, 2, 2>(r); |
| *ys = SkNx_shuffle<1, 3, 1, 3>(r); |
| } |
| |
| static void map_quad_general(const Sk4f& qx, const Sk4f& qy, const SkMatrix& m, |
| Sk4f* xs, Sk4f* ys, Sk4f* ws) { |
| static constexpr auto fma = SkNx_fma<4, float>; |
| *xs = fma(m.getScaleX(), qx, fma(m.getSkewX(), qy, m.getTranslateX())); |
| *ys = fma(m.getSkewY(), qx, fma(m.getScaleY(), qy, m.getTranslateY())); |
| if (m.hasPerspective()) { |
| Sk4f w = fma(m.getPerspX(), qx, fma(m.getPerspY(), qy, m.get(SkMatrix::kMPersp2))); |
| if (ws) { |
| // Output the calculated w coordinates |
| *ws = w; |
| } else { |
| // Apply perspective division immediately |
| Sk4f iw = w.invert(); |
| *xs *= iw; |
| *ys *= iw; |
| } |
| } else if (ws) { |
| *ws = 1.f; |
| } |
| } |
| |
| static void map_rect_general(const SkRect& rect, const SkMatrix& matrix, |
| Sk4f* xs, Sk4f* ys, Sk4f* ws) { |
| Sk4f rx(rect.fLeft, rect.fLeft, rect.fRight, rect.fRight); |
| Sk4f ry(rect.fTop, rect.fBottom, rect.fTop, rect.fBottom); |
| map_quad_general(rx, ry, matrix, xs, ys, ws); |
| } |
| |
| // Rearranges (top-left, top-right, bottom-right, bottom-left) ordered skQuadPts into xs and ys |
| // ordered (top-left, bottom-left, top-right, bottom-right) |
| static void rearrange_sk_to_gr_points(const SkPoint skQuadPts[4], Sk4f* xs, Sk4f* ys) { |
| *xs = Sk4f(skQuadPts[0].fX, skQuadPts[3].fX, skQuadPts[1].fX, skQuadPts[2].fX); |
| *ys = Sk4f(skQuadPts[0].fY, skQuadPts[3].fY, skQuadPts[1].fY, skQuadPts[2].fY); |
| } |
| |
| template <typename Q> |
| void GrResolveAATypeForQuad(GrAAType requestedAAType, GrQuadAAFlags requestedEdgeFlags, |
| const Q& quad, GrQuadType knownType, |
| GrAAType* outAAType, GrQuadAAFlags* outEdgeFlags) { |
| // Most cases will keep the requested types unchanged |
| *outAAType = requestedAAType; |
| *outEdgeFlags = requestedEdgeFlags; |
| |
| switch (requestedAAType) { |
| // When aa type is coverage, disable AA if the edge configuration doesn't actually need it |
| case GrAAType::kCoverage: |
| if (requestedEdgeFlags == GrQuadAAFlags::kNone) { |
| // Turn off anti-aliasing |
| *outAAType = GrAAType::kNone; |
| } else { |
| // For coverage AA, if the quad is a rect and it lines up with pixel boundaries |
| // then overall aa and per-edge aa can be completely disabled |
| if (knownType == GrQuadType::kRect && !quad.aaHasEffectOnRect()) { |
| *outAAType = GrAAType::kNone; |
| *outEdgeFlags = GrQuadAAFlags::kNone; |
| } |
| } |
| break; |
| // For no or msaa anti aliasing, override the edge flags since edge flags only make sense |
| // when coverage aa is being used. |
| case GrAAType::kNone: |
| *outEdgeFlags = GrQuadAAFlags::kNone; |
| break; |
| case GrAAType::kMSAA: |
| *outEdgeFlags = GrQuadAAFlags::kAll; |
| break; |
| case GrAAType::kMixedSamples: |
| SK_ABORT("Should not use mixed sample AA with edge AA flags"); |
| break; |
| } |
| }; |
| |
| // Instantiate GrResolve... for GrQuad and GrPerspQuad |
| template void GrResolveAATypeForQuad(GrAAType, GrQuadAAFlags, const GrQuad&, GrQuadType, |
| GrAAType*, GrQuadAAFlags*); |
| template void GrResolveAATypeForQuad(GrAAType, GrQuadAAFlags, const GrPerspQuad&, GrQuadType, |
| GrAAType*, GrQuadAAFlags*); |
| |
| GrQuadType GrQuadTypeForTransformedRect(const SkMatrix& matrix) { |
| if (matrix.rectStaysRect()) { |
| return GrQuadType::kRect; |
| } else if (matrix.preservesRightAngles()) { |
| return GrQuadType::kRectilinear; |
| } else if (matrix.hasPerspective()) { |
| return GrQuadType::kPerspective; |
| } else { |
| return GrQuadType::kStandard; |
| } |
| } |
| |
| GrQuadType GrQuadTypeForPoints(const SkPoint pts[4], const SkMatrix& matrix) { |
| if (matrix.hasPerspective()) { |
| return GrQuadType::kPerspective; |
| } |
| // If 'pts' was formed by SkRect::toQuad() and not transformed further, it is safe to use the |
| // quad type derived from 'matrix'. Otherwise don't waste any more time and assume kStandard |
| // (most general 2D quad). |
| if ((pts[0].fY == pts[3].fY && pts[1].fY == pts[2].fY) && |
| (pts[0].fX == pts[1].fX && pts[2].fX == pts[3].fX)) { |
| return GrQuadTypeForTransformedRect(matrix); |
| } else { |
| return GrQuadType::kStandard; |
| } |
| } |
| |
| GrQuad GrQuad::MakeFromRect(const SkRect& rect, const SkMatrix& m) { |
| Sk4f x, y; |
| SkMatrix::TypeMask tm = m.getType(); |
| if (tm <= (SkMatrix::kScale_Mask | SkMatrix::kTranslate_Mask)) { |
| map_rect_translate_scale(rect, m, &x, &y); |
| } else { |
| map_rect_general(rect, m, &x, &y, nullptr); |
| } |
| return GrQuad(x, y); |
| } |
| |
| GrQuad GrQuad::MakeFromSkQuad(const SkPoint pts[4], const SkMatrix& matrix) { |
| Sk4f xs, ys; |
| rearrange_sk_to_gr_points(pts, &xs, &ys); |
| if (matrix.isIdentity()) { |
| return GrQuad(xs, ys); |
| } else { |
| Sk4f mx, my; |
| map_quad_general(xs, ys, matrix, &mx, &my, nullptr); |
| return GrQuad(mx, my); |
| } |
| } |
| |
| bool GrQuad::aaHasEffectOnRect() const { |
| SkASSERT(this->quadType() == GrQuadType::kRect); |
| return aa_affects_rect(fX[0], fY[0], fX[3], fY[3]); |
| } |
| |
| // Private constructor used by GrQuadList to quickly fill in a quad's values from the channel arrays |
| GrPerspQuad::GrPerspQuad(const float* xs, const float* ys, const float* ws) { |
| memcpy(fX, xs, 4 * sizeof(float)); |
| memcpy(fY, ys, 4 * sizeof(float)); |
| memcpy(fW, ws, 4 * sizeof(float)); |
| } |
| |
| GrPerspQuad GrPerspQuad::MakeFromRect(const SkRect& rect, const SkMatrix& m) { |
| Sk4f x, y, w; |
| SkMatrix::TypeMask tm = m.getType(); |
| if (tm <= (SkMatrix::kScale_Mask | SkMatrix::kTranslate_Mask)) { |
| map_rect_translate_scale(rect, m, &x, &y); |
| w = 1.f; |
| } else { |
| map_rect_general(rect, m, &x, &y, &w); |
| } |
| return GrPerspQuad(x, y, w); |
| } |
| |
| GrPerspQuad GrPerspQuad::MakeFromSkQuad(const SkPoint pts[4], const SkMatrix& matrix) { |
| Sk4f xs, ys; |
| rearrange_sk_to_gr_points(pts, &xs, &ys); |
| if (matrix.isIdentity()) { |
| return GrPerspQuad(xs, ys, 1.f); |
| } else { |
| Sk4f mx, my, mw; |
| map_quad_general(xs, ys, matrix, &mx, &my, &mw); |
| return GrPerspQuad(mx, my, mw); |
| } |
| } |
| |
| bool GrPerspQuad::aaHasEffectOnRect() const { |
| SkASSERT(this->quadType() == GrQuadType::kRect); |
| // If rect, ws must all be 1s so no need to divide |
| return aa_affects_rect(fX[0], fY[0], fX[3], fY[3]); |
| } |