skia2/example/HelloWorld.cpp
Kevin Lubick 88c15aeb94 [includes] Enforce IWYU on //example
Change-Id: I26136f1a3960eafd6e48c733c16ca35d20534df6
Bug: skia:13052
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/535395
Reviewed-by: Ben Wagner <bungeman@google.com>
2022-04-29 15:39:33 +00:00

165 lines
4.2 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 "example/HelloWorld.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkFont.h"
#include "include/core/SkFontTypes.h"
#include "include/core/SkGraphics.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPoint.h"
#include "include/core/SkRect.h"
#include "include/core/SkShader.h"
#include "include/core/SkString.h"
#include "include/core/SkSurface.h"
#include "include/core/SkTileMode.h"
#include "include/effects/SkGradientShader.h"
#include "tools/sk_app/DisplayParams.h"
#include <string.h>
using namespace sk_app;
Application* Application::Create(int argc, char** argv, void* platformData) {
return new HelloWorld(argc, argv, platformData);
}
HelloWorld::HelloWorld(int argc, char** argv, void* platformData)
#if defined(SK_GL)
: fBackendType(Window::kNativeGL_BackendType),
#elif defined(SK_VULKAN)
: fBackendType(Window::kVulkan_BackendType),
#elif defined(SK_DAWN)
: fBackendType(Window::kDawn_BackendType),
#else
: fBackendType(Window::kRaster_BackendType),
#endif
fRotationAngle(0) {
SkGraphics::Init();
fWindow = Window::CreateNativeWindow(platformData);
fWindow->setRequestedDisplayParams(DisplayParams());
// register callbacks
fWindow->pushLayer(this);
fWindow->attach(fBackendType);
}
HelloWorld::~HelloWorld() {
fWindow->detach();
delete fWindow;
}
void HelloWorld::updateTitle() {
if (!fWindow) {
return;
}
SkString title("Hello World ");
if (Window::kRaster_BackendType == fBackendType) {
title.append("Raster");
} else {
#if defined(SK_GL)
title.append("GL");
#elif defined(SK_VULKAN)
title.append("Vulkan");
#elif defined(SK_DAWN)
title.append("Dawn");
#else
title.append("Unknown GPU backend");
#endif
}
fWindow->setTitle(title.c_str());
}
void HelloWorld::onBackendCreated() {
this->updateTitle();
fWindow->show();
fWindow->inval();
}
void HelloWorld::onPaint(SkSurface* surface) {
auto canvas = surface->getCanvas();
// Clear background
canvas->clear(SK_ColorWHITE);
SkPaint paint;
paint.setColor(SK_ColorRED);
// Draw a rectangle with red paint
SkRect rect = SkRect::MakeXYWH(10, 10, 128, 128);
canvas->drawRect(rect, paint);
// Set up a linear gradient and draw a circle
{
SkPoint linearPoints[] = { { 0, 0 }, { 300, 300 } };
SkColor linearColors[] = { SK_ColorGREEN, SK_ColorBLACK };
paint.setShader(SkGradientShader::MakeLinear(linearPoints, linearColors, nullptr, 2,
SkTileMode::kMirror));
paint.setAntiAlias(true);
canvas->drawCircle(200, 200, 64, paint);
// Detach shader
paint.setShader(nullptr);
}
// Draw a message with a nice black paint
SkFont font;
font.setSubpixel(true);
font.setSize(20);
paint.setColor(SK_ColorBLACK);
canvas->save();
static const char message[] = "Hello World ";
// Translate and rotate
canvas->translate(300, 300);
fRotationAngle += 0.2f;
if (fRotationAngle > 360) {
fRotationAngle -= 360;
}
canvas->rotate(fRotationAngle);
// Draw the text
canvas->drawSimpleText(message, strlen(message), SkTextEncoding::kUTF8, 0, 0, font, paint);
canvas->restore();
}
void HelloWorld::onIdle() {
// Just re-paint continuously
fWindow->inval();
}
bool HelloWorld::onChar(SkUnichar c, skui::ModifierKey modifiers) {
if (' ' == c) {
if (Window::kRaster_BackendType == fBackendType) {
#if defined(SK_GL)
fBackendType = Window::kNativeGL_BackendType;
#elif defined(SK_VULKAN)
fBackendType = Window::kVulkan_BackendType;
#elif defined(SK_DAWN)
fBackendType = Window::kDawn_BackendType;
#else
SkDebugf("No GPU backend configured\n");
return true;
#endif
} else {
fBackendType = Window::kRaster_BackendType;
}
fWindow->detach();
fWindow->attach(fBackendType);
}
return true;
}