Pre-render the sprites for blank/underline/strikethrough

kitty/boss.py

@@ -54,13 +54,12 @@ class Boss(Thread):
         self.signal_fd = handle_unix_signals()
         self.readers = [self.child_fd, self.signal_fd, self.read_wakeup_fd]
         self.writers = [self.child_fd]
-        self.queue_action(self.initialize)
         self.profile = args.profile
         self.window, self.opts = window, opts
         self.screen = Screen(self, 24, 80, opts.scrollback_lines)
-        self.char_grid = CharGrid(self.screen, opts, window_width, window_height)
         self.read_bytes = partial(read_bytes_dump, print) if args.dump_commands else read_bytes
         self.write_buf = memoryview(b'')
+        self.char_grid = CharGrid(self.screen, opts, window_width, window_height)
         glfw.glfwSetCharModsCallback(window, self.on_text_input)
         glfw.glfwSetKeyCallback(window, self.on_key)
         glfw.glfwSetMouseButtonCallback(window, self.on_mouse_button)
@@ -95,10 +94,6 @@ class Boss(Thread):
             if signal.SIGINT in signals or signal.SIGTERM in signals:
                 self.shutdown()
 
-    def initialize(self):
-        self.char_grid.initialize()
-        glfw.glfwPostEmptyEvent()
-
     def on_focus(self, window, focused):
         if focused:
             if self.screen.enable_focus_tracking():

kitty/char_grid.py

@@ -172,17 +172,14 @@ class CharGrid:
         self.render_queue.put(RenderData(
             viewport=Size(self.width, self.height), clear_color=color_as_int(self.original_bg),
             cursor=self.default_cursor))
-        self.sprites.ensure_state()
         self.clear_count = 4
-
-    def destroy(self):
-        self.sprites.destroy()
-
-    def initialize(self):
         self.default_bg = color_as_int(self.original_bg)
         self.default_fg = color_as_int(self.original_fg)
         self.apply_opts(self.opts)
 
+    def destroy(self):
+        self.sprites.destroy()
+
     def apply_opts(self, opts):
         self.dpix, self.dpiy = get_logical_dpi()
         self.opts = opts

kitty/develop_gl.py

@@ -42,7 +42,6 @@ class Renderer:
         self.color_profile = ColorProfile()
         self.program = ShaderProgram(*cell_shader)
         self.sprites = Sprites()
-        self.sprites.initialize()
         self.do_layout()
 
     def on_resize(self, window, w, h):

kitty/fonts.py

@@ -249,7 +249,7 @@ def add_curl(buf, position, thickness):
             buf[offset + x] = 255
 
 
-def render_cell(text, bold=False, italic=False, underline=0, strikeout=False):
+def render_cell(text=' ', bold=False, italic=False, underline=0, strikeout=False):
     # TODO: Handle non-normalizable combining chars. Probably need to use
     # harfbuzz for that
     text = unicodedata.normalize('NFC', text)[0]

kitty/shaders.py

@@ -46,11 +46,8 @@ class Sprites:
         self.texture_id = self.buffer_id = self.buffer_texture_id = None
         self.last_num_of_layers = 1
         self.last_ynum = -1
-
-    def initialize(self):
         self.texture_unit = GL_TEXTURE0
         self.backend = SpriteMap(glGetIntegerv(GL_MAX_TEXTURE_SIZE), glGetIntegerv(GL_MAX_ARRAY_TEXTURE_LAYERS))
-        self.do_layout(getattr(self, 'cell_width', 1), getattr(self, 'cell_height', 1))
 
     def do_layout(self, cell_width=1, cell_height=1):
         self.cell_width, self.cell_height = cell_width, cell_height
@@ -58,6 +55,25 @@ class Sprites:
         if self.texture_id is not None:
             glDeleteTexture(self.texture_id)
             self.texture_id = None
+        self.ensure_state()
+        self.pre_render()
+
+    def pre_render(self):
+        # Pre-render the basic cells to ensure they have known sprite numbers
+
+        def send(*a, **kw):
+            buf = render_cell(*a, **kw)[0]
+            x, y, z = self.backend.increment()
+            self.send_to_gpu(x, y, z, buf)
+            return x
+
+        send()  # blank
+        send(underline=1)
+        send(strikeout=True)
+        send(underline=1, strikeout=True)
+        send(underline=2)
+        if send(underline=2, strikeout=True) != 5:
+            raise RuntimeError('Available OpenGL texture size is too small')
 
     @property
     def layout(self):
@@ -82,12 +98,10 @@ class Sprites:
         glBindTexture(tgt, self.texture_id)
         glPixelStorei(GL_UNPACK_ALIGNMENT, 1)
         x, y = x * self.cell_width, y * self.cell_height
-        glTexSubImage3D(tgt, 0, x, y, self.backend.z, self.cell_width, self.cell_height, 1, GL_RED, GL_UNSIGNED_BYTE, addressof(buf))
+        glTexSubImage3D(tgt, 0, x, y, z, self.cell_width, self.cell_height, 1, GL_RED, GL_UNSIGNED_BYTE, addressof(buf))
         glBindTexture(tgt, 0)
 
     def realloc_texture(self):
-        if self.texture_id is None:
-            self.initialize()
         tgt = GL_TEXTURE_2D_ARRAY
         tex = glGenTextures(1)
         glBindTexture(tgt, tex)

kitty/sprites.c

@@ -46,6 +46,7 @@ layout(SpriteMap *self, PyObject *args) {
     self->xnum = MAX(1, self->max_texture_size / cell_width);
     self->max_y = MAX(1, self->max_texture_size / cell_height);
     self->ynum = 1;
+    self->x = 0; self->y = 0; self->z = 0;
 
     for (size_t i = 0; i < sizeof(self->cache)/sizeof(self->cache[0]); i++) {
         SpritePosition *s = &(self->cache[i]);
@@ -62,7 +63,7 @@ layout(SpriteMap *self, PyObject *args) {
 }
 
 static void
-increment(SpriteMap *self, int *error) {
+do_increment(SpriteMap *self, int *error) {
     self->x++;
     if (self->x >= self->xnum) {
         self->x = 0; self->y++;
@@ -100,7 +101,7 @@ sprite_position_for(SpriteMap *self, char_type ch, combining_type cc, bool is_se
     s->filled = true;
     s->rendered = false;
     s->x = self->x; s->y = self->y; s->z = self->z;
-    increment(self, error);
+    do_increment(self, error);
     self->dirty = true;
     return s;
 }
@@ -116,6 +117,16 @@ static void set_sprite_error(int error) {
     }
 }
 
+static PyObject*
+increment(SpriteMap *self) {
+#define increment_doc "Increment the current position and return the old (x, y, z) values"
+    unsigned int x = self->x, y = self->y, z = self->z;
+    int error = 0;
+    do_increment(self, &error);
+    if (error) { set_sprite_error(error); return NULL; }
+    return Py_BuildValue("III", x, y, z);
+}
+
 static PyObject*
 position_for(SpriteMap *self, PyObject *args) {
 #define position_for_doc "position_for(ch, cc, is_second) -> x, y, z the sprite position for the specified text"
@@ -217,6 +228,7 @@ static PyMethodDef methods[] = {
     METHOD(position_for, METH_VARARGS)
     METHOD(render_dirty_cells, METH_VARARGS)
     METHOD(update_cell_data, METH_VARARGS)
+    METHOD(increment, METH_NOARGS)
     {NULL}  /* Sentinel */
 };