replace qt with cairo/pango/epoll

meson.build

@@ -3,7 +3,9 @@ project('somebar', ['c', 'cpp'],
 
 wayland_dep = dependency('wayland-client')
 wayland_cursor_dep = dependency('wayland-cursor')
-qt5_dep = dependency('qt5', modules: ['Core', 'Gui'])
+cairo_dep = dependency('cairo')
+pango_dep = dependency('pango')
+pangocairo_dep = dependency('pangocairo')
 
 subdir('protocols')
 
@@ -12,4 +14,10 @@ executable('somebar',
   'src/shm_buffer.cpp',
   'src/bar.cpp',
   wayland_sources,
-  dependencies: [wayland_dep, wayland_cursor_dep, qt5_dep])
+  dependencies: [
+    wayland_dep,
+    wayland_cursor_dep,
+    cairo_dep,
+    pango_dep,
+    pangocairo_dep,
+  ])

src/bar.cpp

@@ -1,11 +1,14 @@
-// somebar - dwl bar
+// somebar - dwl barbar
 // See LICENSE file for copyright and license details.
 
-#include <QColor>
+#include <wayland-client-protocol.h>
-#include <QImage>
+#include <pango/pangocairo.h>
-#include <QPainter>
 #include "bar.hpp"
+#include "cairo.h"
 #include "config.hpp"
+#include "pango/pango-font.h"
+#include "pango/pango-fontmap.h"
+#include "pango/pango-layout.h"
 
 const zwlr_layer_surface_v1_listener Bar::_layerSurfaceListener = {
     [](void *owner, zwlr_layer_surface_v1*, uint32_t serial, uint32_t width, uint32_t height)
@@ -21,25 +24,60 @@ const wl_callback_listener Bar::_frameListener = {
     }
 };
 
-static QFont getFont()
+struct Font {
+    PangoFontDescription *description;
+    int height {0};
+};
+static Font getFont()
 {
-    QFont font {fontFamily, fontSizePt};
+    auto fontMap = pango_cairo_font_map_get_default();
-    font.setBold(fontBold);
+    auto fontDesc = pango_font_description_from_string(font);
-    return font;
+    auto tempContext = pango_font_map_create_context(fontMap);
-}
+    auto font = pango_font_map_load_font(fontMap, tempContext, fontDesc);
-static QFont font = getFont();
+    auto metrics = pango_font_get_metrics(font, pango_language_get_default());
-static QFontMetrics fontMetrics = QFontMetrics {font};
 
-const wl_surface* Bar::surface() const { return _surface.get(); }
+    auto res = Font {};
+    res.description = fontDesc;
+    res.height = PANGO_PIXELS(pango_font_metrics_get_height(metrics));
+
+    pango_font_metrics_unref(metrics);
+    g_object_unref(font);
+    g_object_unref(tempContext);
+    g_object_unref(fontMap);
+    return res;
+}
+static Font barfont = getFont();
+
+BarComponent::BarComponent() { }
+BarComponent::BarComponent(wl_unique_ptr<PangoLayout> layout) : pangoLayout {std::move(layout)} {}
+int BarComponent::width() const
+{
+    int w, h;
+    pango_layout_get_size(pangoLayout.get(), &w, &h);
+    return PANGO_PIXELS(w);
+}
+void BarComponent::setText(const std::string &text)
+{
+    auto chars = new char[text.size()];
+    text.copy(chars, text.size());
+    _text.reset(chars);
+    pango_layout_set_text(pangoLayout.get(), chars, text.size());
+}
 
 Bar::Bar(Monitor *mon)
 {
     _mon = mon;
+    _pangoContext.reset(pango_font_map_create_context(pango_cairo_font_map_get_default()));
     for (auto i=0u; i<tagNames.size(); i++) {
-        _tags.push_back({ ZNET_TAPESOFTWARE_DWL_WM_MONITOR_V1_TAG_STATE_NONE, 0, 0, 0 });
+        _tags.push_back({ ZNET_TAPESOFTWARE_DWL_WM_MONITOR_V1_TAG_STATE_NONE, 0, 0, createComponent(tagNames[i]) });
     }
+    _layoutCmp = createComponent();
+    _titleCmp = createComponent();
+    _statusCmp = createComponent();
 }
 
+const wl_surface* Bar::surface() const { return _surface.get(); }
+
 void Bar::create(wl_output *output)
 {
     _surface.reset(wl_compositor_create_surface(compositor));
@@ -50,27 +88,47 @@ void Bar::create(wl_output *output)
     zwlr_layer_surface_v1_set_anchor(_layerSurface.get(),
         anchor | ZWLR_LAYER_SURFACE_V1_ANCHOR_LEFT | ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT);
 
-    auto barSize = fontMetrics.ascent() + fontMetrics.descent() + paddingY * 2;
+    auto barSize = barfont.height + paddingY * 2;
-    _textY = fontMetrics.ascent() + paddingY;
-
     zwlr_layer_surface_v1_set_size(_layerSurface.get(), 0, barSize);
     zwlr_layer_surface_v1_set_exclusive_zone(_layerSurface.get(), barSize);
     wl_surface_commit(_surface.get());
 }
 
+
+void Bar::setTag(int tag, znet_tapesoftware_dwl_wm_monitor_v1_tag_state state, int numClients, int focusedClient)
+{
+    auto& t = _tags[tag];
+    t.state = state;
+    t.numClients = numClients;
+    t.focusedClient = focusedClient;
+}
+void Bar::setSelected(bool selected) { _selected = selected; }
+void Bar::setLayout(int layout) { _layoutCmp.setText(layoutNames[layout]); }
+void Bar::setTitle(const std::string &title) { _titleCmp.setText(title); }
+void Bar::setStatus(const std::string &status) { _statusCmp.setText(status); }
+
+void Bar::invalidate()
+{
+    if (_invalid) return;
+    _invalid = true;
+    auto frame = wl_surface_frame(_surface.get());
+    wl_callback_add_listener(frame, &_frameListener, this);
+    wl_surface_commit(_surface.get());
+}
+
 void Bar::click(int x, int, int btn)
 {
     Arg arg = {0};
     Arg *argp = nullptr;
     int control = ClkNone;
-    if (x > _statusX) {
+    if (x > _statusCmp.x) {
         control = ClkStatusText;
-    } else if (x > _titleX) {
+    } else if (x > _titleCmp.x) {
         control = ClkWinTitle;
-    } else if (x > _layoutX) {
+    } else if (x > _layoutCmp.x) {
         control = ClkLayoutSymbol;
     } else for (auto tag = _tags.size()-1; tag >= 0; tag--) {
-        if (x > _tags[tag].x) {
+        if (x > _tags[tag].component.x) {
             control = ClkTagBar;
             arg.ui = 1<<tag;
             argp = &arg;
@@ -86,28 +144,6 @@ void Bar::click(int x, int, int btn)
     }
 }
 
-void Bar::invalidate()
-{
-    if (_invalid) return;
-    _invalid = true;
-    auto frame = wl_surface_frame(_surface.get());
-    wl_callback_add_listener(frame, &_frameListener, this);
-    wl_surface_commit(_surface.get());
-}
-
-void Bar::setTag(int tag, znet_tapesoftware_dwl_wm_monitor_v1_tag_state state, int numClients, int focusedClient)
-{
-    auto& t = _tags[tag];
-    t.state = state;
-    t.numClients = numClients;
-    t.focusedClient = focusedClient;
-}
-
-void Bar::setSelected(bool selected) { _selected = selected; }
-void Bar::setLayout(int layout) { _layout = layout; }
-void Bar::setTitle(const char *title) { _title = title; }
-void Bar::setStatus(const QString &status) { _status = status; }
-
 void Bar::layerSurfaceConfigure(uint32_t serial, uint32_t width, uint32_t height)
 {
     zwlr_layer_surface_v1_ack_configure(_layerSurface.get(), serial);
@@ -117,24 +153,22 @@ void Bar::layerSurfaceConfigure(uint32_t serial, uint32_t width, uint32_t height
 
 void Bar::render()
 {
-    auto img = QImage {
+    auto img = wl_unique_ptr<cairo_surface_t> {cairo_image_surface_create_for_data(
         _bufs->data(),
+        CAIRO_FORMAT_ARGB32,
         _bufs->width,
         _bufs->height,
-        _bufs->stride,
+        _bufs->stride
-        QImage::Format_ARGB32
+    )};
-    };
+    auto painter = wl_unique_ptr<cairo_t> {cairo_create(img.get())};
-    auto painter = QPainter {&img};
+    _painter = painter.get();
-    _painter = &painter;
+    pango_cairo_update_context(_painter, _pangoContext.get());
     _x = 0;
-    painter.setFont(font);
 
     renderTags();
     setColorScheme(_selected ? colorActive : colorInactive);
-    _layoutX = _x;
+    renderComponent(_layoutCmp);
-    renderText(layoutNames[_layout]);
+    renderComponent(_titleCmp);
-    _titleX = _x;
-    renderText(_title);
     renderStatus();
     
     _painter = nullptr;
@@ -145,50 +179,68 @@ void Bar::render()
     _invalid = false;
 }
 
-void Bar::setColorScheme(const ColorScheme &scheme, bool invert)
-{
-    _painter->setBrush(QBrush {invert ? scheme.fg : scheme.bg});
-    _painter->setPen(QPen {QBrush {invert ? scheme.bg : scheme.fg}, 1});
-}
-
 void Bar::renderTags()
 {
-    for (auto i=0u; i<_tags.size(); i++) {
+    for (auto &tag : _tags) {
-        auto& tag = _tags[i];
-        tag.x = _x;
         setColorScheme(
             tag.state & ZNET_TAPESOFTWARE_DWL_WM_MONITOR_V1_TAG_STATE_ACTIVE ? colorActive : colorInactive,
             tag.state & ZNET_TAPESOFTWARE_DWL_WM_MONITOR_V1_TAG_STATE_URGENT);
-        renderText(tagNames[i]);
+        renderComponent(tag.component);
-        auto indicators = qMin(tag.numClients, _bufs->height/2);
+        auto indicators = std::min(tag.numClients, _bufs->height/2);
         for (auto ind = 0; ind < indicators; ind++) {
-            if (ind == tag.focusedClient) {
+            auto w = ind == tag.focusedClient ? 7 : 1;
-                _painter->drawLine(tag.x, ind*2, tag.x+5, ind*2);
+            cairo_move_to(_painter, tag.component.x, ind*2+0.5);
-            } else {
+            cairo_rel_line_to(_painter, w, 0);
-                _painter->drawPoint(tag.x, ind*2);
+            cairo_close_path(_painter);
-            }
+            cairo_set_line_width(_painter, 1);
+            cairo_stroke(_painter);
         }
     }
 }
 
-void Bar::renderText(const QString &text)
+void Bar::renderStatus()
 {
-    auto size = textWidth(text) + paddingX*2;
+    pango_cairo_update_layout(_painter, _statusCmp.pangoLayout.get());
-    _painter->fillRect(_x, 0, size, _bufs->height, _painter->brush());
+    beginBg();
-    _painter->drawText(paddingX+_x, _textY, text);
+    auto start = _bufs->width - _statusCmp.width() - paddingX*2;
+    cairo_rectangle(_painter, _x, 0, _bufs->width-_x+start, _bufs->height);
+    cairo_fill(_painter);
+
+    _x = start;
+    renderComponent(_statusCmp);
+}
+
+void Bar::setColorScheme(const ColorScheme &scheme, bool invert)
+{
+    _colorScheme = invert
+        ? ColorScheme {scheme.bg, scheme.fg}
+        : ColorScheme {scheme.fg, scheme.bg};
+}
+static void setColor(cairo_t *painter, const Color &color) { cairo_set_source_rgba(painter, color.r/255.0, color.g/255.0, color.b/255.0, color.a/255.0); }
+void Bar::beginFg() { setColor(_painter, _colorScheme.fg); }
+void Bar::beginBg() { setColor(_painter, _colorScheme.bg); }
+
+void Bar::renderComponent(BarComponent &component)
+{
+    pango_cairo_update_layout(_painter, component.pangoLayout.get());
+    auto size = component.width() + paddingX*2;
+    component.x = _x;
+
+    beginBg();
+    cairo_rectangle(_painter, _x, 0, size, _bufs->height);
+    cairo_fill(_painter);
+    cairo_move_to(_painter, _x+paddingX, paddingY);
+
+    beginFg();
+    pango_cairo_show_layout(_painter, component.pangoLayout.get());
     _x += size;
 }
 
-void Bar::renderStatus()
+BarComponent Bar::createComponent(const std::string &initial)
 {
-    _painter->fillRect(_x, 0, _bufs->width-_x, _bufs->height, _painter->brush());
+    auto layout = pango_layout_new(_pangoContext.get());
-    auto size = textWidth(_status) + paddingX;
+    pango_layout_set_font_description(layout, barfont.description);
-    _statusX = _bufs->width - size;
+    auto res = BarComponent {wl_unique_ptr<PangoLayout> {layout}};
-    _painter->drawText(paddingX+_statusX, _textY, _status);
+    res.setText(initial);
-    _x = _bufs->width;
+    return res;
-}
-
-int Bar::textWidth(const QString &text)
-{
-    return fontMetrics.size(Qt::TextSingleLine, text).width();
 }

src/bar.hpp

@@ -3,20 +3,29 @@
 
 #pragma once
 #include <optional>
+#include <string>
 #include <vector>
 #include <wayland-client.h>
-#include <QString>
-#include <QFontMetrics>
-#include <QPainter>
 #include "wlr-layer-shell-unstable-v1-client-protocol.h"
 #include "common.hpp"
 #include "shm_buffer.hpp"
 
+class BarComponent {
+    std::unique_ptr<char[]> _text;
+public:
+    BarComponent();
+    explicit BarComponent(wl_unique_ptr<PangoLayout> layout);
+    int width() const;
+    void setText(const std::string &text);
+    wl_unique_ptr<PangoLayout> pangoLayout;
+    int x {0};
+};
+
 struct Tag {
     znet_tapesoftware_dwl_wm_monitor_v1_tag_state state;
     int numClients;
     int focusedClient;
-    int x;
+    BarComponent component;
 };
 
 struct Monitor;
@@ -26,35 +35,39 @@ class Bar {
 
     wl_unique_ptr<wl_surface> _surface;
     wl_unique_ptr<zwlr_layer_surface_v1> _layerSurface;
+    wl_unique_ptr<PangoContext> _pangoContext;
     Monitor *_mon;
-    QPainter *_painter {nullptr};
     std::optional<ShmBuffer> _bufs;
-    int _textY, _x;
+    std::vector<Tag> _tags;
-    int _statusX, _titleX, _layoutX;
+    BarComponent _layoutCmp, _titleCmp, _statusCmp;
+    bool _selected;
     bool _invalid {false};
 
-    std::vector<Tag> _tags;
+    // only vaild during render()
-    int _layout;
+    cairo_t *_painter {nullptr};
-    bool _selected;
+    int  _x;
-    QString _title;
+    ColorScheme _colorScheme;
-    QString _status;
 
     void layerSurfaceConfigure(uint32_t serial, uint32_t width, uint32_t height);
     void render();
     void renderTags();
     void renderStatus();
-    void renderText(const QString &text);
+
-    int textWidth(const QString &text);
+    // low-level rendering
     void setColorScheme(const ColorScheme &scheme, bool invert=false);
+    void beginFg();
+    void beginBg();
+    void renderComponent(BarComponent &component);
+    BarComponent createComponent(const std::string &initial = {});
 public:
     Bar(Monitor *mon);
     const wl_surface* surface() const;
     void create(wl_output *output);
-    void setSelected(bool selected);
     void setTag(int tag, znet_tapesoftware_dwl_wm_monitor_v1_tag_state state, int numClients, int focusedClient);
+    void setSelected(bool selected);
     void setLayout(int layout);
-    void setTitle(const char *title);
+    void setTitle(const std::string &title);
-    void setStatus(const QString &status);
+    void setStatus(const std::string &status);
     void invalidate();
     void click(int x, int y, int btn);
 };

src/common.hpp

@@ -3,16 +3,22 @@
 
 #pragma once
 #include <memory>
+#include <string>
 #include <vector>
 #include <wayland-client.h>
 #include <linux/input-event-codes.h>
-#include <QColor>
+#include <cairo/cairo.h>
-#include <QString>
+#include <pango/pango.h>
 #include "wlr-layer-shell-unstable-v1-client-protocol.h"
 #include "net-tapesoftware-dwl-wm-unstable-v1-client-protocol.h"
 
+struct Color {
+    Color() {}
+    constexpr Color(uint8_t r, uint8_t g, uint8_t b, uint8_t a=255) : r(r), g(g), b(b), a(a) { }
+    uint8_t r, g, b, a {255};
+};
 struct ColorScheme {
-    QColor fg, bg;
+    Color fg, bg;
 };
 union Arg {
 	unsigned int ui;
@@ -32,8 +38,8 @@ extern wl_display *display;
 extern wl_compositor *compositor;
 extern wl_shm *shm;
 extern zwlr_layer_shell_v1 *wlrLayerShell;
-extern std::vector<QString> tagNames;
+extern std::vector<std::string> tagNames;
-extern std::vector<QString> layoutNames;
+extern std::vector<std::string> layoutNames;
 
 void view(Monitor &m, const Arg &arg);
 void toggleview(Monitor &m, const Arg &arg);
@@ -57,3 +63,9 @@ WL_DELETER(wl_seat, wl_seat_release);
 WL_DELETER(wl_surface, wl_surface_destroy);
 WL_DELETER(znet_tapesoftware_dwl_wm_monitor_v1, znet_tapesoftware_dwl_wm_monitor_v1_release);
 WL_DELETER(zwlr_layer_surface_v1, zwlr_layer_surface_v1_destroy);
+
+WL_DELETER(cairo_t, cairo_destroy);
+WL_DELETER(cairo_surface_t, cairo_surface_destroy);
+
+WL_DELETER(PangoContext, g_object_unref);
+WL_DELETER(PangoLayout, g_object_unref);

src/config.hpp

@@ -9,12 +9,11 @@ constexpr bool topbar = true;
 constexpr int paddingX = 10;
 constexpr int paddingY = 3;
 
-constexpr const char *fontFamily = "Source Sans Pro";
+// See https://docs.gtk.org/Pango/type_func.FontDescription.from_string.html
-constexpr int fontSizePt = 12;
+constexpr const char *font = "Source Sans Pro 12";
-constexpr bool fontBold = false;
 
-constexpr ColorScheme colorInactive = {QColor(0xbb, 0xbb, 0xbb), QColor(0x22, 0x22, 0x22)};
+constexpr ColorScheme colorInactive = {Color(0xbb, 0xbb, 0xbb), Color(0x22, 0x22, 0x22)};
-constexpr ColorScheme colorActive = {QColor(0xee, 0xee, 0xee), QColor(0x00, 0x55, 0x77)};
+constexpr ColorScheme colorActive = {Color(0xee, 0xee, 0xee), Color(0x00, 0x55, 0x77)};
 constexpr const char *termcmd[] = {"foot", nullptr};
 
 constexpr Button buttons[] = {

src/main.cpp

@@ -1,10 +1,14 @@
 // somebar - dwl bar
 // See LICENSE file for copyright and license details.
 
-#include <cstdio>
+#include <stdio.h>
 #include <fcntl.h>
 #include <math.h>
 #include <signal.h>
+#include <algorithm>
+#include <list>
+#include <optional>
+#include <vector>
 #include <sys/epoll.h>
 #include <sys/mman.h>
 #include <sys/signalfd.h>
@@ -12,13 +16,8 @@
 #include <sys/types.h>
 #include <unistd.h>
 #include <linux/input-event-codes.h>
-#include <list>
-#include <optional>
-#include <vector>
 #include <wayland-client.h>
 #include <wayland-cursor.h>
-#include <QGuiApplication>
-#include <QString>
 #include "wlr-layer-shell-unstable-v1-client-protocol.h"
 #include "xdg-shell-client-protocol.h"
 #include "net-tapesoftware-dwl-wm-unstable-v1-client-protocol.h"
@@ -57,15 +56,15 @@ wl_compositor *compositor;
 wl_shm *shm;
 zwlr_layer_shell_v1 *wlrLayerShell;
 znet_tapesoftware_dwl_wm_v1 *dwlWm;
-std::vector<QString> tagNames;
+std::vector<std::string> tagNames;
-std::vector<QString> layoutNames;
+std::vector<std::string> layoutNames;
 static xdg_wm_base *xdgWmBase;
 static wl_surface *cursorSurface;
 static wl_cursor_image *cursorImage;
 static bool ready;
 static std::list<Monitor> monitors;
 static std::list<Seat> seats;
-static QString lastStatus;
+static std::string lastStatus;
 static std::string statusFifoName;
 static int epoll {-1};
 static int displayFd {-1};
@@ -277,7 +276,7 @@ static void onStatus()
 {
     char buffer[512];
     auto n = read(statusFifoFd, buffer, sizeof(buffer));
-    lastStatus = QString::fromUtf8(buffer, n);
+    lastStatus = {buffer, (unsigned long) n};
     for (auto &monitor : monitors) {
         if (monitor.bar) {
             monitor.bar->setStatus(lastStatus);
@@ -343,8 +342,6 @@ int main(int argc, char **argv)
     sigaddset(&blockedsigs, SIGTERM);
     sigprocmask(SIG_BLOCK, &blockedsigs, nullptr);
 
-    QGuiApplication app {argc, argv};
-
     epoll_event epollEv = {0};
     std::array<epoll_event, 5> epollEvents;
     epoll = epoll_create1(EPOLL_CLOEXEC);