add shm_buffer class

This commit is contained in:
Raphael Robatsch 2021-10-20 20:20:27 +02:00
parent 4e4b82e478
commit d8098fccc0
6 changed files with 109 additions and 25 deletions

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@ -10,6 +10,7 @@ subdir('protocols')
executable('somebar',
'src/main.cpp',
'src/shm_buffer.cpp',
wayland_sources,
#moc,
dependencies: [qt5_dep, wayland_dep])

16
src/bar.hpp Normal file
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@ -0,0 +1,16 @@
// somebar - dwl bar
// See LICENSE file for copyright and license details.
#pragma once
#include <wayland-client.h>
#include "wlr-layer-shell-unstable-v1-client-protocol.h"
#include "common.hpp"
#include "shm_buffer.hpp"
class Bar {
wl_surface *_surface {nullptr};
zwlr_layer_surface_v1 *_layerSurface {nullptr};
ShmBuffer _bufs;
public:
explicit Bar(wl_output *output);
};

13
src/common.hpp Normal file
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@ -0,0 +1,13 @@
// somebar - dwl bar
// See LICENSE file for copyright and license details.
#pragma once
#include <wayland-client.h>
#include "wlr-layer-shell-unstable-v1-client-protocol.h"
void waylandFlush();
extern wl_display *display;
extern wl_compositor *compositor;
extern wl_shm *shm;
extern zwlr_layer_shell_v1 *wlrLayerShell;

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@ -11,18 +11,18 @@
#include "qnamespace.h"
#include "wlr-layer-shell-unstable-v1-client-protocol.h"
#include "xdg-shell-client-protocol.h"
#include "common.hpp"
#include "shm_buffer.hpp"
constexpr uint32_t barSize = 20;
static void waylandFlush();
static void waylandWriteReady();
static void requireGlobal(const void *p, const char *name);
// wayland globals
static wl_display *display;
static wl_compositor *compositor;
static wl_shm *shm;
static zwlr_layer_shell_v1 *wlrLayerShell;
wl_display *display;
wl_compositor *compositor;
wl_shm *shm;
zwlr_layer_shell_v1 *wlrLayerShell;
static QSocketNotifier *displayWriteNotifier;
static xdg_wm_base *xdgWmBase;
@ -33,37 +33,25 @@ static const struct xdg_wm_base_listener xdgWmBaseListener = {
}
};
static const struct wl_buffer_listener wlBufferListener {
[](void*, wl_buffer *buffer) {
wl_buffer_destroy(buffer);
}
};
// app globals
static wl_surface *surface;
static zwlr_layer_surface_v1 *layerSurface;
static const struct wl_surface_listener surfaceListener = {
// todo
};
static ShmBuffer *xbuf;
static const struct zwlr_layer_surface_v1_listener layerSurfaceListener = {
[](void*, zwlr_layer_surface_v1 *layerSurface, uint32_t serial, uint32_t width, uint32_t height) {
zwlr_layer_surface_v1_ack_configure(layerSurface, serial);
printf("configured to %d x %d\n", width, height);
auto stride = width * 4;
auto size = stride * height;
auto fd = memfd_create("somebar-surface", MFD_CLOEXEC);
ftruncate(fd, size);
auto buffer = reinterpret_cast<char*>(mmap(nullptr, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0));
auto pool = wl_shm_create_pool(shm, fd, size);
auto wlBuffer = wl_shm_pool_create_buffer(pool, 0, width, height, stride, WL_SHM_FORMAT_XRGB8888);
wl_shm_pool_destroy(pool);
close(fd);
xbuf = new ShmBuffer(width, height, WL_SHM_FORMAT_XRGB8888);
auto buffer = xbuf->data();
auto w = 2*M_PI/(width / 10);
for (auto x = 0; x < width; x++) {
auto val = 255*(sin(x*w)/2+0.5);
for (auto y = 0; y < height; y++) {
auto p = &buffer[y*stride+x*4];
auto p = &buffer[y*xbuf->stride+x*4];
*p++ = 0;
*p++ = 0;
*p++ = val;
@ -71,8 +59,7 @@ static const struct zwlr_layer_surface_v1_listener layerSurfaceListener = {
}
}
wl_buffer_add_listener(wlBuffer, &wlBufferListener, nullptr);
wl_surface_attach(surface, wlBuffer, 0, 0);
wl_surface_attach(surface, xbuf->buffer(), 0, 0);
wl_surface_commit(surface);
waylandFlush();
}
@ -156,7 +143,7 @@ int main(int argc, char **argv)
return app.exec();
}
static void waylandFlush()
void waylandFlush()
{
wl_display_dispatch_pending(display);
if (wl_display_flush(display) < 0 && errno == EAGAIN) {

42
src/shm_buffer.cpp Normal file
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@ -0,0 +1,42 @@
// somebar - dwl bar
// See LICENSE file for copyright and license details.
#include <sys/mman.h>
#include <unistd.h>
#include "shm_buffer.hpp"
#include "common.hpp"
constexpr int n = 2;
ShmBuffer::ShmBuffer(int w, int h, wl_shm_format format)
: width(w)
, height(h)
, stride(w*4)
{
auto oneSize = stride*h;
_totalSize = oneSize * n;
auto fd = memfd_create("wl_shm", MFD_CLOEXEC);
ftruncate(fd, _totalSize);
auto pool = wl_shm_create_pool(shm, fd, _totalSize);
auto ptr = reinterpret_cast<char*>(mmap(nullptr, _totalSize, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0));
close(fd);
for (auto i=0; i<n; i++) {
auto offset = oneSize*i;
auto buffer = wl_shm_pool_create_buffer(pool, offset, width, height, stride, format);
_buffers[i] = { ptr+offset, buffer };
}
wl_shm_pool_destroy(pool);
}
ShmBuffer::~ShmBuffer()
{
munmap(_buffers[0].data, _totalSize);
for (auto i=0; i<n; i++) {
wl_buffer_destroy(_buffers[i].buffer);
}
waylandFlush();
}
char* ShmBuffer::data() const { return _buffers[_current].data; }
wl_buffer* ShmBuffer::buffer() const { return _buffers[_current].buffer; }
void ShmBuffer::flip() { _current = 1-_current; }

25
src/shm_buffer.hpp Normal file
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@ -0,0 +1,25 @@
// somebar - dwl bar
// See LICENSE file for copyright and license details.
#pragma once
#include <array>
#include <wayland-client.h>
// double buffered shm
// format is must be 32-bit
class ShmBuffer {
struct Buf {
char *data {nullptr};
wl_buffer *buffer {nullptr};
};
std::array<Buf, 2> _buffers;
int _current {0};
size_t _totalSize {0};
public:
int width, height, stride;
explicit ShmBuffer(int width, int height, wl_shm_format format);
char* data() const;
wl_buffer* buffer() const;
void flip();
~ShmBuffer();
};