Move logical DPI calculation into glfw module

Now DPI state is maintained in only one central place.

kitty/fonts/box_drawing.py

@@ -7,7 +7,7 @@
 from functools import partial as p
 from itertools import repeat
 
-from kitty.utils import get_logical_dpi
+from kitty.fast_data_types import pt_to_px_ceil
 
 scale = (0.001, 1, 1.5, 2)
 
@@ -18,9 +18,8 @@ def set_scale(new_scale):
 
 
 def thickness(level=1, horizontal=True):
-    dpi = get_logical_dpi()[0 if horizontal else 1]
     pts = scale[level]
-    return int(math.ceil(pts * dpi / 72.0))
+    return pt_to_px_ceil(pts)
 
 
 def draw_hline(buf, width, x1, x2, y, level):

kitty/fonts/render.py

@@ -170,7 +170,6 @@ def render_box_drawing(codepoint):
 
 
 def setup_for_testing(family='monospace', size=11.0, dpi=96.0):
-    from kitty.utils import get_logical_dpi
     opts = defaults._replace(font_family=family)
     set_options(opts)
     sprites = {}
@@ -181,7 +180,6 @@ def send_to_gpu(x, y, z, data):
     sprite_map_set_limits(100000, 100)
     set_send_sprite_to_gpu(send_to_gpu)
     set_logical_dpi(dpi, dpi)
-    get_logical_dpi((dpi, dpi))
     cell_width, cell_height = set_font_family(opts, override_font_size=size)
     prerender()
     return sprites, cell_width, cell_height

kitty/glfw.c

@@ -209,6 +209,60 @@ make_os_window_context_current(OSWindow *w) {
     }
 }
 
+
+static GLFWmonitor*
+current_monitor(GLFWwindow *window) {
+    // Find the monitor that has the maximum overlap with this window
+    int nmonitors, i;
+    int wx, wy, ww, wh;
+    int mx, my, mw, mh;
+    int overlap = 0, bestoverlap = 0;
+    GLFWmonitor *bestmonitor = NULL;
+    GLFWmonitor **monitors = NULL;
+    const GLFWvidmode *mode;
+
+    glfwGetWindowPos(window, &wx, &wy);
+    glfwGetWindowSize(window, &ww, &wh);
+    monitors = glfwGetMonitors(&nmonitors);
+    if (monitors == NULL || nmonitors < 1) { PyErr_SetString(PyExc_ValueError, "No monitors connected"); return NULL; }
+
+    for (i = 0; i < nmonitors; i++) {
+        mode = glfwGetVideoMode(monitors[i]);
+        glfwGetMonitorPos(monitors[i], &mx, &my);
+        mw = mode->width;
+        mh = mode->height;
+
+        overlap =
+            MAX(0, MIN(wx + ww, mx + mw) - MAX(wx, mx)) *
+            MAX(0, MIN(wy + wh, my + mh) - MAX(wy, my));
+
+        if (bestoverlap < overlap || bestmonitor == NULL) {
+            bestoverlap = overlap;
+            bestmonitor = monitors[i];
+        }
+    }
+
+    return bestmonitor;
+}
+
+
+static inline void
+set_dpi_from_window(OSWindow *w) {
+    GLFWmonitor *monitor = NULL;
+    if (w) { monitor = current_monitor(w->handle); }
+    if (monitor == NULL) monitor = glfwGetPrimaryMonitor();
+    float xscale = 1, yscale = 1;
+    if (monitor) glfwGetMonitorContentScale(monitor, &xscale, &yscale);
+#ifdef __APPLE__
+    double factor = 72.0;
+#else
+    double factor = 96.0;
+#endif
+    global_state.logical_dpi_x = xscale * factor;
+    global_state.logical_dpi_y = yscale * factor;
+}
+
+
 static PyObject*
 create_os_window(PyObject UNUSED *self, PyObject *args) {
     int width, height, visible = 1, swap_interval = 0, x = -1, y = -1;
@@ -256,6 +310,7 @@ create_os_window(PyObject UNUSED *self, PyObject *args) {
     current_os_window_ctx = glfw_window;
     glfwSwapInterval(swap_interval);  // a value of 1 makes mouse selection laggy
     if (is_first_window) { 
+        set_dpi_from_window(NULL);
         gl_init();
         PyObject *ret = PyObject_CallFunction(load_programs, "i", glfwGetWindowAttrib(glfw_window, GLFW_TRANSPARENT_FRAMEBUFFER));
         if (ret == NULL) return NULL;
@@ -443,41 +498,6 @@ set_clipboard_string(PyObject UNUSED *self, PyObject *args) {
     Py_RETURN_NONE;
 }
 
-static GLFWmonitor*
-current_monitor(GLFWwindow *window) {
-    // Find the monitor that has the maximum overlap with this window
-    int nmonitors, i;
-    int wx, wy, ww, wh;
-    int mx, my, mw, mh;
-    int overlap = 0, bestoverlap = 0;
-    GLFWmonitor *bestmonitor = NULL;
-    GLFWmonitor **monitors = NULL;
-    const GLFWvidmode *mode;
-
-    glfwGetWindowPos(window, &wx, &wy);
-    glfwGetWindowSize(window, &ww, &wh);
-    monitors = glfwGetMonitors(&nmonitors);
-    if (monitors == NULL || nmonitors < 1) { PyErr_SetString(PyExc_ValueError, "No monitors connected"); return NULL; }
-
-    for (i = 0; i < nmonitors; i++) {
-        mode = glfwGetVideoMode(monitors[i]);
-        glfwGetMonitorPos(monitors[i], &mx, &my);
-        mw = mode->width;
-        mh = mode->height;
-
-        overlap =
-            MAX(0, MIN(wx + ww, mx + mw) - MAX(wx, mx)) *
-            MAX(0, MIN(wy + wh, my + mh) - MAX(wy, my));
-
-        if (bestoverlap < overlap || bestmonitor == NULL) {
-            bestoverlap = overlap;
-            bestmonitor = monitors[i];
-        }
-    }
-
-    return bestmonitor;
-}
-
 static PyObject*
 toggle_fullscreen(PyObject UNUSED *self) {
     GLFWmonitor *monitor;

kitty/main.py

@@ -15,12 +15,11 @@
 from .constants import glfw_path, is_macos, is_wayland, logo_data_file
 from .fast_data_types import (
     change_wcwidth, create_os_window, glfw_init, glfw_terminate,
-    install_sigchld_handler, set_default_window_icon, set_logical_dpi,
+    install_sigchld_handler, set_default_window_icon, set_options, show_window
-    set_options, show_window
 )
 from .fonts.box_drawing import set_scale
 from .utils import (
-    detach, encode_wm_class, end_startup_notification, get_logical_dpi,
+    detach, encode_wm_class, end_startup_notification,
     init_startup_notification, single_instance
 )
 from .window import load_shader_programs
@@ -49,7 +48,6 @@ def run_app(opts, args):
     if not is_wayland and not is_macos:  # no window icons on wayland
         with open(logo_data_file, 'rb') as f:
             set_default_window_icon(f.read(), 256, 256)
-    set_logical_dpi(*get_logical_dpi())
     boss = Boss(window_id, opts, args)
     boss.start()
     end_startup_notification(startup_ctx)

kitty/state.c

@@ -6,6 +6,7 @@
  */
 
 #include "state.h"
+#include <math.h>
 
 GlobalState global_state = {{0}};
 
@@ -424,7 +425,13 @@ PYWRAP1(set_logical_dpi) {
 PYWRAP1(pt_to_px) {
     long pt = PyLong_AsLong(args);
     double dpi = (global_state.logical_dpi_x + global_state.logical_dpi_y) / 2.f;
-    return PyLong_FromLong((long)(pt * (dpi / 72.0)));
+    return PyLong_FromLong((long)round((pt * (dpi / 72.0))));
+}
+
+PYWRAP1(pt_to_px_ceil) {
+    long pt = PyLong_AsLong(args);
+    double dpi = (global_state.logical_dpi_x + global_state.logical_dpi_y) / 2.f;
+    return PyLong_FromLong((long)ceil((pt * (dpi / 72.0))));
 }
 
 
@@ -468,6 +475,7 @@ static PyMethodDef module_methods[] = {
     MW(handle_for_window_id, METH_VARARGS),
     MW(set_logical_dpi, METH_VARARGS),
     MW(pt_to_px, METH_O),
+    MW(pt_to_px_ceil, METH_O),
     MW(add_tab, METH_O),
     MW(add_window, METH_VARARGS),
     MW(update_window_title, METH_VARARGS),

kitty/utils.py

@@ -19,8 +19,8 @@
 
 from .constants import appname, is_macos, is_wayland
 from .fast_data_types import (
-    GLSL_VERSION, glfw_primary_monitor_content_scale,
+    GLSL_VERSION, redirect_std_streams, wcwidth as wcwidth_impl, x11_display,
-    redirect_std_streams, wcwidth as wcwidth_impl, x11_display, x11_window_id
+    x11_window_id
 )
 from .rgb import Color, to_color
 
@@ -65,19 +65,6 @@ def sanitize_title(x):
     return re.sub(r'\s+', ' ', re.sub(r'[\0-\x19]', '', x))
 
 
-def get_logical_dpi(override_dpi=None):
-    # See https://github.com/glfw/glfw/issues/1019 for why we cant use
-    # glfw_get_physical_dpi()
-    if override_dpi is not None:
-        get_logical_dpi.ans = override_dpi
-    if not hasattr(get_logical_dpi, 'ans'):
-        factor = 72.0 if is_macos else 96.0
-        xscale, yscale = glfw_primary_monitor_content_scale()
-        xdpi, ydpi = xscale * factor, yscale * factor
-        get_logical_dpi.ans = xdpi, ydpi
-    return get_logical_dpi.ans
-
-
 def color_as_int(val):
     return val[0] << 16 | val[1] << 8 | val[2]
 

kitty_tests/fonts.py

@@ -14,7 +14,6 @@
 from kitty.fonts.render import (
     prerender, render_string, set_font_family, shape_string
 )
-from kitty.utils import get_logical_dpi
 
 from . import BaseTest
 
@@ -30,7 +29,6 @@ def send_to_gpu(x, y, z, data):
 
         set_send_sprite_to_gpu(send_to_gpu)
         set_logical_dpi(96.0, 96.0)
-        get_logical_dpi((96.0, 96.0))
         self.cell_width, self.cell_height = set_font_family()
         prerender()
         self.assertEqual([k[0] for k in self.sprites], [0, 1, 2, 3, 4, 5])