CS代考计算机代写 #include “canvaswidget.h”

#include “canvaswidget.h”

#include
#include

#include
#include

using graphics101::Image;
using graphics101::ColorRGBA8;

namespace
{
QImage QImageFromImage( const Image& image )
{
return QImage( reinterpret_cast< const uchar* >( image.data() ), image.width(), image.height(), QImage::Format_RGBA8888 );
}
}

CanvasWidget::CanvasWidget(QWidget *parent) : QWidget(parent)
{
modified = false;

image = Image();

radius = 25;
color = Qt::blue;
color.setAlpha(64);
shape = graphics101::Quadratic;
flowRate = 66;
flowRateTimerID = 0;
painting = false;

updateBrushImage();
}

void CanvasWidget::clear()
{
image.fill( ColorRGBA8(255,255,255) );
modified = false;
update();
}

bool CanvasWidget::saveToPath( const QString& path )
{
// Since we don’t shrink the canvas when the user resizes the canvas smaller,
// we might have extra canvas. Save only the visible part.
const Image visible = Image( image ).resize( size().width(), size().height() );
const bool success = visible.save( path.toStdString() );
// After successfully saving, we no longer have unsaved changes.
if( success ) modified = false;
return success;
}

bool CanvasWidget::loadFromPath( const QString& path )
{
Image loaded;
const bool success = loaded.load( path.toStdString() );

// After successfully loading, we no longer have unsaved changes.
if( success ) {
modified = false;

// Always resize the loaded image to the current view size if bigger.
image = loaded.resize(
std::max( loaded.width(), size().width() ),
std::max( loaded.height(), size().height() ),
ColorRGBA8(255,255,255,255)
);

update();
}

return success;
}

QImage CanvasWidget::getBrushImage() const
{
return QImageFromImage( airbrush_image );
}

void CanvasWidget::setRadius(int r)
{
assert( r > 0 );

radius = r;

updateBrushImage();
}
void CanvasWidget::setFlowRate(int f)
{
assert( f >= 0 );

flowRate = f;
}
void CanvasWidget::setShape(const QString& str)
{
shape = graphics101::AirBrushShapeFromString( str.toStdString() );

updateBrushImage();
}
void CanvasWidget::setColor(const QColor& c)
{
color = c;

updateBrushImage();
}

void CanvasWidget::mousePressEvent(QMouseEvent *event)
{
painting = true;
// Save the position for the flow rate
lastPos = event->pos();
brushAt( lastPos );
// If the flowRate is > 0, start a timer for that many milliseconds.
if( flowRate > 0 ) {
flowRateTimerID = startTimer( flowRate );
}
}
void CanvasWidget::mouseMoveEvent(QMouseEvent *event)
{
if( !painting ) return;
// Save the position for the flow rate
lastPos = event->pos();
brushAt( lastPos );
}
void CanvasWidget::mouseReleaseEvent(QMouseEvent *event)
{
painting = false;

// Cancel the flow rate timer.
if( flowRateTimerID != 0 ) killTimer( flowRateTimerID );
flowRateTimerID = 0;
}
void CanvasWidget::paintEvent(QPaintEvent *event)
{
// Create a drawing context.
QPainter painter( this );
// Redraw the “dirty” region.
const QRect dirty = event->rect();
painter.drawImage( dirty, QImageFromImage( image ), dirty );
}
void CanvasWidget::resizeEvent(QResizeEvent *event)
{
// If either the width or height got bigger, make the image bigger.
if( width() > image.width() || height() > image.height() ) {
// To avoid resizing with every increased pixel, resize by CHUNK at a time.
const int CHUNK = 128;
const QSize newsize(
std::max( width() + CHUNK, image.width() ),
std::max( height() + CHUNK, image.height() )
);
// Resize and fill newly visible areas with white.
image.resize( newsize.width(), newsize.height(), ColorRGBA8( 255,255,255,255 ) );
// Update to repaint everything.
update();
}
// Bubble the resize event up.
QWidget::resizeEvent( event );
}
void CanvasWidget::timerEvent(QTimerEvent *event)
{
brushAt( lastPos );
}

void CanvasWidget::brushAt(const QPoint &point)
{
// Step 1. Modify `image` pixels.
const graphics101::Rect dirty = graphics101::paint_at( image, airbrush_image, point.x(), point.y() );

// Step 2. Call update() to mark the painted part of the screen as dirty.
// Pass a tighter rectangle for better performance.
update( QRect( dirty.x, dirty.y, dirty.width, dirty.height ) );
modified = true;
}

void CanvasWidget::updateBrushImage()
{
const ColorRGBA8 c( color.red(), color.green(), color.blue(), color.alpha() );
graphics101::create_airbrush( airbrush_image, shape, radius, c );
emit brushChanged( QImageFromImage( airbrush_image ) );
}