kwin/src/backends/drm/dumb_swapchain.cpp
Vlad Zahorodnii d89501a079 Move platform backends to backends directory
This improves file organization in kwin by putting backends in a single
directory.

It also makes easier to discover kwin's low level components for new
contributors because the plugins directory may come as the last place to
look for. When one hears "plugin", the first thing that comes to mind is
regular plugins, not low level backends.
2021-11-02 09:02:41 +00:00

67 lines
1.5 KiB
C++

/*
KWin - the KDE window manager
This file is part of the KDE project.
SPDX-FileCopyrightText: 2021 Xaver Hugl <xaver.hugl@gmail.com>
SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "dumb_swapchain.h"
#include "drm_gpu.h"
#include "logging.h"
namespace KWin
{
DumbSwapchain::DumbSwapchain(DrmGpu *gpu, const QSize &size)
: m_size(size)
{
for (int i = 0; i < 2; i++) {
auto buffer = QSharedPointer<DrmDumbBuffer>::create(gpu, size);
if (!buffer->bufferId()) {
break;
}
if (!buffer->map()) {
break;
}
buffer->image()->fill(Qt::black);
m_slots.append(Slot{.buffer = buffer, .age = 0,});
}
if (m_slots.count() < 2) {
qCWarning(KWIN_DRM) << "Failed to create dumb buffers for swapchain!";
m_slots.clear();
}
}
QSharedPointer<DrmDumbBuffer> DumbSwapchain::acquireBuffer(int *age)
{
if (m_slots.isEmpty()) {
return nullptr;
}
index = (index + 1) % m_slots.count();
if (age) {
*age = m_slots[index].age;
}
return m_slots[index].buffer;
}
QSharedPointer<DrmDumbBuffer> DumbSwapchain::currentBuffer() const
{
return m_slots[index].buffer;
}
void DumbSwapchain::releaseBuffer(QSharedPointer<DrmDumbBuffer> buffer)
{
Q_ASSERT(m_slots[index].buffer == buffer);
for (qsizetype i = 0; i < m_slots.count(); ++i) {
if (m_slots[i].buffer == buffer) {
m_slots[i].age = 1;
} else if (m_slots[i].age > 0) {
m_slots[i].age++;
}
}
}
}