| /* |
| * Copyright 2020 Google LLC |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "gm/gm.h" |
| #include "include/core/SkCanvas.h" |
| #include "include/core/SkMatrix.h" |
| #include "include/core/SkRect.h" |
| #include "src/base/SkFloatBits.h" |
| |
| // This tests a scenario where when the 2D projection of a perspective quad is inset we degenerate |
| // the inset 2d geometry to a triangle because an inset vertex crosses the opposite edge. When we |
| // project back to 3D and try to move the original verts along the original edges so that they |
| // project to the 2D points. Whether an edge can be moved along depends on whether the adjacent edge |
| // at the vertex is AA. However, in the degenerate triangle case the 2D point may not fall along |
| // either of the edges. Thus, if we're constrained to moving along one edge and solve for X or Y the |
| // other value may go wildly away from projecting to the 2D value. The current approach is to force |
| // AA on at both edges that meet at a vertex whose inset point has been replaced by an off-edge |
| // point if either is AA originally. This gives us an additional vector to move along so that we can |
| // find a 3D point that projects to the 2D point in both X and Y. |
| DEF_SIMPLE_GM(crbug_1162942, canvas, 620, 200) { |
| // Matrix and quad values taken from Chrome repro scenario. |
| SkMatrix ctm = SkMatrix::MakeAll( |
| SkBits2Float(0x3FCC7F75), SkBits2Float(0x3D5784FC), SkBits2Float(0x44C48C99), |
| SkBits2Float(0x3F699F7F), SkBits2Float(0x3E0A0D37), SkBits2Float(0x43908518), |
| SkBits2Float(0x3AA17423), SkBits2Float(0x3A6CCDC3), SkBits2Float(0x3F2EFEEC)); |
| ctm.postTranslate(-1500.f, -325.f); |
| |
| SkPoint pts[4] = {{SkBits2Float(0x3F39778B), SkBits2Float(0x43FF7FFC)}, |
| {SkBits2Float(0x0), SkBits2Float(0x43FF7FFA)}, |
| {SkBits2Float(0xB83B055E), SkBits2Float(0x42500003)}, |
| {SkBits2Float(0x3F39776F), SkBits2Float(0x4250000D)}}; |
| SkRect bounds; |
| bounds.setBounds(pts, 4); |
| |
| canvas->clear(SK_ColorWHITE); |
| |
| SkCanvas::QuadAAFlags flags[] = { |
| (SkCanvas::QuadAAFlags) (SkCanvas::kTop_QuadAAFlag | SkCanvas::kLeft_QuadAAFlag ), |
| (SkCanvas::QuadAAFlags) (SkCanvas::kBottom_QuadAAFlag | SkCanvas::kRight_QuadAAFlag), |
| (SkCanvas::QuadAAFlags) (SkCanvas::kBottom_QuadAAFlag), |
| (SkCanvas::QuadAAFlags) (SkCanvas::kRight_QuadAAFlag), |
| (SkCanvas::QuadAAFlags) (SkCanvas::kRight_QuadAAFlag | SkCanvas::kLeft_QuadAAFlag), |
| (SkCanvas::QuadAAFlags) (SkCanvas::kTop_QuadAAFlag | SkCanvas::kBottom_QuadAAFlag), |
| }; |
| |
| SkColor color = SK_ColorGREEN; |
| for (auto aaFlags : flags) { |
| canvas->save(); |
| canvas->concat(ctm); |
| canvas->experimental_DrawEdgeAAQuad(bounds, pts, aaFlags, color, SkBlendMode::kSrcOver); |
| SkColor rgb = color & 0x00FFFFFF; |
| color = 0xFF000000 | (rgb << 4) | (rgb >> 20); |
| canvas->restore(); |
| canvas->translate(0, 25); |
| } |
| } |
| |