skia2/tests/ShadowTest.cpp
Jim Van Verth 3645bb069d Fix some shadow issues.
* Clamp path polygon points to nearest 1/16th of a pixel to help
  with floating point issues.
* Added check for multiple contour paths.
* Return empty SkVertices for certain degenerate cases to avoid
  unnecessary blurs.
* Check iteration count in SkOffsetPolygon to avoid infinite loops.
* Add new tests to verify these.

Bug: skia:
Change-Id: Ie6ad48d2504e065dcc822609d369f90c56ef3ad3
Reviewed-on: https://skia-review.googlesource.com/136701
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
2018-06-26 20:28:55 +00:00

172 lines
6.0 KiB
C++

/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkCanvas.h"
#include "SkDrawShadowInfo.h"
#include "SkPath.h"
#include "SkShadowTessellator.h"
#include "SkShadowUtils.h"
#include "SkVertices.h"
#include "Test.h"
enum ExpectVerts {
kDont_ExpectVerts,
kDo_ExpectVerts
};
void check_result(skiatest::Reporter* reporter, sk_sp<SkVertices> verts,
ExpectVerts expectVerts, bool expectSuccess) {
if (expectSuccess != SkToBool(verts)) {
ERRORF(reporter, "Expected shadow tessellation to %s but it did not.",
expectSuccess ? "succeed" : "fail");
}
if (SkToBool(verts)) {
if (kDont_ExpectVerts == expectVerts && verts->vertexCount()) {
ERRORF(reporter, "Expected shadow tessellation to generate no vertices but it did.");
} else if (kDo_ExpectVerts == expectVerts && !verts->vertexCount()) {
ERRORF(reporter, "Expected shadow tessellation to generate vertices but it didn't.");
}
}
}
void tessellate_shadow(skiatest::Reporter* reporter, const SkPath& path, const SkMatrix& ctm,
const SkPoint3& heightParams, ExpectVerts expectVerts, bool expectSuccess) {
auto verts = SkShadowTessellator::MakeAmbient(path, ctm, heightParams, true);
check_result(reporter, verts, expectVerts, expectSuccess);
verts = SkShadowTessellator::MakeAmbient(path, ctm, heightParams, false);
check_result(reporter, verts, expectVerts, expectSuccess);
verts = SkShadowTessellator::MakeSpot(path, ctm, heightParams, {0, 0, 128}, 128.f, false);
check_result(reporter, verts, expectVerts, expectSuccess);
verts = SkShadowTessellator::MakeSpot(path, ctm, heightParams, {0, 0, 128}, 128.f, false);
check_result(reporter, verts, expectVerts, expectSuccess);
}
DEF_TEST(ShadowUtils, reporter) {
SkCanvas canvas(100, 100);
SkPath path;
path.cubicTo(100, 50, 20, 100, 0, 0);
tessellate_shadow(reporter, path, canvas.getTotalMatrix(), {0, 0, 4}, kDo_ExpectVerts, true);
// super high path
tessellate_shadow(reporter, path, canvas.getTotalMatrix(), {0, 0, 4.0e+37f},
kDo_ExpectVerts, true);
// This line segment has no area and no shadow.
path.reset();
path.lineTo(10.f, 10.f);
tessellate_shadow(reporter, path, canvas.getTotalMatrix(), {0, 0, 4}, kDont_ExpectVerts, true);
// A series of collinear line segments
path.reset();
for (int i = 0; i < 10; ++i) {
path.lineTo((SkScalar)i, (SkScalar)i);
}
tessellate_shadow(reporter, path, canvas.getTotalMatrix(), {0, 0, 4}, kDont_ExpectVerts, true);
// ugly degenerate path
path.reset();
path.moveTo(-134217728, 2.22265153e+21f);
path.cubicTo(-2.33326106e+21f, 7.36298265e-41f, 3.72237738e-22f, 5.99502692e-36f,
1.13631943e+22f, 2.0890786e+33f);
path.cubicTo(1.03397626e-25f, 5.99502692e-36f, 9.18354962e-41f, 0, 4.6142745e-37f, -213558848);
path.lineTo(-134217728, 2.2226515e+21f);
tessellate_shadow(reporter, path, canvas.getTotalMatrix(), {0, 0, 9}, kDont_ExpectVerts, true);
// simple concave path (star of David)
path.reset();
path.moveTo(0.0f, -50.0f);
path.lineTo(14.43f, -25.0f);
path.lineTo(43.30f, -25.0f);
path.lineTo(28.86f, 0.0f);
path.lineTo(43.30f, 25.0f);
path.lineTo(14.43f, 25.0f);
path.lineTo(0.0f, 50.0f);
path.lineTo(-14.43f, 25.0f);
path.lineTo(-43.30f, 25.0f);
path.lineTo(-28.86f, 0.0f);
path.lineTo(-43.30f, -25.0f);
path.lineTo(-14.43f, -25.0f);
// uncomment when transparent concave shadows are working
// tessellate_shadow(reporter, path, canvas.getTotalMatrix(), {0, 0, 9}, kDo_ExpectVerts, true);
// complex concave path (bowtie)
path.reset();
path.moveTo(-50, -50);
path.lineTo(-50, 50);
path.lineTo(50, -50);
path.lineTo(50, 50);
path.lineTo(-50, -50);
tessellate_shadow(reporter, path, canvas.getTotalMatrix(), {0, 0, 9}, kDont_ExpectVerts, false);
// multiple contour path
path.close();
path.moveTo(0, 0);
path.lineTo(1, 0);
path.lineTo(0, 1);
tessellate_shadow(reporter, path, canvas.getTotalMatrix(), {0, 0, 9}, kDont_ExpectVerts, false);
}
void check_xformed_bounds(skiatest::Reporter* reporter, const SkPath& path, const SkMatrix& ctm) {
const SkDrawShadowRec rec = {
SkPoint3::Make(0, 0, 4),
SkPoint3::Make(100, 0, 600),
800.f,
0x08000000,
0x40000000,
0
};
SkRect bounds;
SkDrawShadowMetrics::GetLocalBounds(path, rec, ctm, &bounds);
ctm.mapRect(&bounds);
auto verts = SkShadowTessellator::MakeAmbient(path, ctm, rec.fZPlaneParams, true);
if (verts) {
REPORTER_ASSERT(reporter, bounds.contains(verts->bounds()));
}
SkPoint mapXY = ctm.mapXY(rec.fLightPos.fX, rec.fLightPos.fY);
SkPoint3 devLightPos = SkPoint3::Make(mapXY.fX, mapXY.fY, rec.fLightPos.fZ);
verts = SkShadowTessellator::MakeSpot(path, ctm, rec.fZPlaneParams, devLightPos,
rec.fLightRadius, false);
if (verts) {
REPORTER_ASSERT(reporter, bounds.contains(verts->bounds()));
}
}
void check_bounds(skiatest::Reporter* reporter, const SkPath& path) {
SkMatrix ctm;
ctm.setTranslate(100, 100);
check_xformed_bounds(reporter, path, ctm);
ctm.postScale(2, 2);
check_xformed_bounds(reporter, path, ctm);
ctm.preRotate(45);
check_xformed_bounds(reporter, path, ctm);
ctm.preSkew(40, -20);
check_xformed_bounds(reporter, path, ctm);
ctm[SkMatrix::kMPersp0] = 0.0001f;
ctm[SkMatrix::kMPersp1] = 12.f;
check_xformed_bounds(reporter, path, ctm);
}
DEF_TEST(ShadowBounds, reporter) {
SkPath path;
path.addRRect(SkRRect::MakeRectXY(SkRect::MakeLTRB(-50, -20, 40, 30), 4, 4));
check_bounds(reporter, path);
path.reset();
path.addOval(SkRect::MakeLTRB(300, 300, 900, 900));
check_bounds(reporter, path);
path.reset();
path.cubicTo(100, 50, 20, 100, 0, 0);
check_bounds(reporter, path);
}