ladybird/Userland/Applications/PDFViewer/PDFViewer.cpp
2021-05-18 16:35:23 +02:00

102 lines
2.9 KiB
C++

/*
* Copyright (c) 2021, Matthew Olsson <mattco@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "PDFViewer.h"
#include <LibGUI/Action.h>
#include <LibGUI/Painter.h>
#include <LibPDF/Renderer.h>
PDFViewer::PDFViewer()
{
set_should_hide_unnecessary_scrollbars(true);
set_focus_policy(GUI::FocusPolicy::StrongFocus);
set_scrollbars_enabled(true);
}
PDFViewer::~PDFViewer()
{
}
void PDFViewer::set_document(RefPtr<PDF::Document> document)
{
m_document = document;
m_current_page_index = document->get_first_page_index();
update();
}
RefPtr<Gfx::Bitmap> PDFViewer::get_rendered_page(u32 index)
{
auto existing_rendered_page = m_rendered_pages.get(index);
if (existing_rendered_page.has_value())
return existing_rendered_page.value();
auto rendered_page = render_page(m_document->get_page(index));
m_rendered_pages.set(index, rendered_page);
return rendered_page;
}
void PDFViewer::paint_event(GUI::PaintEvent& event)
{
GUI::Frame::paint_event(event);
GUI::Painter painter(*this);
painter.add_clip_rect(widget_inner_rect());
painter.add_clip_rect(event.rect());
painter.fill_rect(event.rect(), Color(0x80, 0x80, 0x80));
if (!m_document)
return;
painter.translate(frame_thickness(), frame_thickness());
painter.translate(-horizontal_scrollbar().value(), -vertical_scrollbar().value());
auto page = get_rendered_page(m_current_page_index);
auto total_width = width() - frame_thickness() * 2;
auto total_height = height() - frame_thickness() * 2;
auto bitmap_width = page->width();
auto bitmap_height = page->height();
Gfx::IntPoint p { (total_width - bitmap_width) / 2, (total_height - bitmap_height) / 2 };
painter.blit(p, *page, page->rect());
}
void PDFViewer::mousewheel_event(GUI::MouseEvent& event)
{
if (event.wheel_delta() > 0) {
if (m_current_page_index < m_document->get_page_count() - 1)
m_current_page_index++;
} else if (m_current_page_index > 0) {
m_current_page_index--;
}
update();
}
RefPtr<Gfx::Bitmap> PDFViewer::render_page(const PDF::Page& page)
{
float page_width = page.media_box.upper_right_x - page.media_box.lower_left_x;
float page_height = page.media_box.upper_right_y - page.media_box.lower_left_y;
float page_scale_factor = page_height / page_width;
float width = 300.0f;
float height = width * page_scale_factor;
auto bitmap = Gfx::Bitmap::create(Gfx::BitmapFormat::BGRA8888, { width, height });
PDF::Renderer::render(*m_document, page, bitmap);
if (page.rotate != 0) {
int rotation_count = (page.rotate / 90) % 4;
if (rotation_count == 3) {
bitmap = bitmap->rotated(Gfx::RotationDirection::CounterClockwise);
} else {
for (int i = 0; i < rotation_count; i++)
bitmap = bitmap->rotated(Gfx::RotationDirection::Clockwise);
}
}
return bitmap;
}