blob: 985d854585251bae6efd49aff81b0f559f2006fc [file] [log] [blame]
// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "ui/gfx/shadow_util.h"
#include <map>
#include <vector>
#include "base/lazy_instance.h"
#include "base/memory/ptr_util.h"
#include "third_party/skia/include/core/SkDrawLooper.h"
#include "third_party/skia/include/core/SkRRect.h"
#include "ui/gfx/canvas.h"
#include "ui/gfx/geometry/insets.h"
#include "ui/gfx/image/canvas_image_source.h"
#include "ui/gfx/shadow_value.h"
#include "ui/gfx/skia_paint_util.h"
#include "ui/gfx/skia_util.h"
namespace gfx {
namespace {
// Creates an image with the given shadows painted around a round rect with
// the given corner radius. The image will be just large enough to paint the
// shadows appropriately with a 1px square region reserved for "content".
class ShadowNineboxSource : public CanvasImageSource {
ShadowNineboxSource(const std::vector<ShadowValue>& shadows,
float corner_radius)
: CanvasImageSource(CalculateSize(shadows, corner_radius)),
corner_radius_(corner_radius) {
~ShadowNineboxSource() override {}
// CanvasImageSource overrides:
void Draw(Canvas* canvas) override {
cc::PaintFlags flags;
Insets insets = -ShadowValue::GetMargin(shadows_);
gfx::Rect bounds(size());
SkRRect r_rect = SkRRect::MakeRectXY(gfx::RectToSkRect(bounds),
corner_radius_, corner_radius_);
// Clip out the center so it's not painted with the shadow.
canvas->sk_canvas()->clipRRect(r_rect, SkClipOp::kDifference, true);
// Clipping alone is not enough --- due to anti aliasing there will still be
// some of the fill color in the rounded corners. We must make the fill
// color transparent.
canvas->sk_canvas()->drawRRect(r_rect, flags);
static Size CalculateSize(const std::vector<ShadowValue>& shadows,
float corner_radius) {
// The "content" area (the middle tile in the 3x3 grid) is a single pixel.
gfx::Rect bounds(0, 0, 1, 1);
// We need enough space to render the full range of blur.
// We also need space for the full roundrect corner rounding.
return bounds.size();
const std::vector<ShadowValue> shadows_;
const float corner_radius_;
// Map from elevation/corner radius pair to a cached shadow.
using ShadowDetailsMap = std::map<std::pair<int, int>, ShadowDetails>;
base::LazyInstance<ShadowDetailsMap>::DestructorAtExit g_shadow_cache =
} // namespace
ShadowDetails::ShadowDetails() {}
ShadowDetails::ShadowDetails(const ShadowDetails& other) = default;
ShadowDetails::~ShadowDetails() {}
const ShadowDetails& ShadowDetails::Get(int elevation, int corner_radius) {
auto iter =
g_shadow_cache.Get().find(std::make_pair(elevation, corner_radius));
if (iter != g_shadow_cache.Get().end())
return iter->second;
auto insertion = g_shadow_cache.Get().emplace(
std::make_pair(elevation, corner_radius), ShadowDetails());
ShadowDetails* shadow = &insertion.first->second;
shadow->values = ShadowValue::MakeMdShadowValues(elevation);
auto* source = new ShadowNineboxSource(shadow->values, corner_radius);
shadow->ninebox_image = ImageSkia(base::WrapUnique(source), source->size());
return *shadow;
} // namespace gfx