kitty/kitty/shaders.py
2017-09-15 10:45:22 +05:30

140 lines
5.6 KiB
Python

#!/usr/bin/env python
# vim:fileencoding=utf-8
# License: GPL v3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
import sys
from ctypes import addressof
from .fast_data_types import (
GL_CLAMP_TO_EDGE, GL_MAX_ARRAY_TEXTURE_LAYERS, GL_MAX_TEXTURE_SIZE,
GL_NEAREST, GL_R8, GL_RED, GL_TEXTURE0, GL_TEXTURE_2D_ARRAY,
GL_TEXTURE_MAG_FILTER, GL_TEXTURE_MIN_FILTER, GL_TEXTURE_WRAP_S,
GL_TEXTURE_WRAP_T, GL_UNPACK_ALIGNMENT, GL_UNSIGNED_BYTE,
copy_image_sub_data, glActiveTexture, glBindTexture, glCopyImageSubData,
glDeleteTexture, glGenTextures, glGetIntegerv, glPixelStorei,
glTexParameteri, glTexStorage3D, glTexSubImage3D, render_dirty_sprites,
sprite_map_current_layout, sprite_map_free, sprite_map_increment,
sprite_map_set_layout, sprite_map_set_limits
)
from .fonts.render import render_cell
from .utils import safe_print
class Sprites:
''' Maintain sprite sheets of all rendered characters on the GPU as a texture
array with each texture being a sprite sheet. '''
# TODO: Rewrite this class using the ARB_shader_image_load_store and ARB_shader_storage_buffer_object
# extensions one they become available.
def __init__(self):
self.xnum = self.ynum = 1
self.first_cell_cache = {}
self.second_cell_cache = {}
self.x = self.y = self.z = 0
self.texture_id = None
self.last_num_of_layers = 1
self.last_ynum = -1
self.sampler_num = 0
self.texture_unit = GL_TEXTURE0 + self.sampler_num
sprite_map_set_limits(glGetIntegerv(GL_MAX_TEXTURE_SIZE), glGetIntegerv(GL_MAX_ARRAY_TEXTURE_LAYERS))
def do_layout(self, cell_width=1, cell_height=1):
self.cell_width, self.cell_height = cell_width, cell_height
sprite_map_set_layout(cell_width or 1, cell_height or 1)
if self.texture_id is not None:
glDeleteTexture(self.texture_id)
self.texture_id = None
self.ensure_state()
# 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 = sprite_map_increment()
self.send_to_gpu(x, y, z, buf)
return x
send() # blank
send(underline=1)
send(underline=2)
if send(strikethrough=True) != 3:
raise RuntimeError('Available OpenGL texture size is too small')
def render_cell(self, text, bold, italic, is_second):
first, second = render_cell(text, bold, italic)
ans = second if is_second else first
return ans or render_cell()[0]
def render_dirty_sprites(self):
ret = render_dirty_sprites()
if ret:
for text, bold, italic, is_second, x, y, z in ret:
cell = self.render_cell(text, bold, italic, is_second)
self.send_to_gpu(x, y, z, cell)
def send_to_gpu(self, x, y, z, buf):
xnum, ynum, znum = sprite_map_current_layout()
if znum >= self.last_num_of_layers:
self.realloc_texture()
else:
if znum == 0 and ynum > self.last_ynum:
self.realloc_texture()
tgt = GL_TEXTURE_2D_ARRAY
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, z, self.cell_width, self.cell_height, 1, GL_RED, GL_UNSIGNED_BYTE, addressof(buf))
def realloc_texture(self):
tgt = GL_TEXTURE_2D_ARRAY
tex = glGenTextures(1)
glBindTexture(tgt, tex)
# We use GL_NEAREST otherwise glyphs that touch the edge of the cell
# often show a border between cells
glTexParameteri(tgt, GL_TEXTURE_MIN_FILTER, GL_NEAREST)
glTexParameteri(tgt, GL_TEXTURE_MAG_FILTER, GL_NEAREST)
glTexParameteri(tgt, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE)
glTexParameteri(tgt, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE)
xnum, bynum, z = sprite_map_current_layout()
znum = z + 1
width, height = xnum * self.cell_width, bynum * self.cell_height
glTexStorage3D(tgt, 1, GL_R8, width, height, znum)
if self.texture_id is not None:
ynum = bynum
if z == 0:
ynum -= 1 # Only copy the previous rows
try:
glCopyImageSubData(self.texture_id, tgt, 0, 0, 0, 0, tex, tgt, 0, 0, 0, 0,
width, ynum * self.cell_height, self.last_num_of_layers)
except RuntimeError:
# OpenGL does not have ARB_copy_image
if not hasattr(self, 'realloc_warned'):
safe_print(
'WARNING: Your system\'s OpenGL implementation does not have glCopyImageSubData, falling back to a slower implementation',
file=sys.stderr)
self.realloc_warned = True
copy_image_sub_data(self.texture_id, tex, width, ynum * self.cell_height, self.last_num_of_layers)
glBindTexture(tgt, tex)
glDeleteTexture(self.texture_id)
self.last_num_of_layers = znum
self.last_ynum = bynum
self.texture_id = tex
def destroy(self):
sprite_map_free()
if self.texture_id is not None:
glDeleteTexture(self.texture_id)
self.texture_id = None
def ensure_state(self):
if self.texture_id is None:
self.realloc_texture()
def __enter__(self):
self.ensure_state()
glActiveTexture(self.texture_unit)
glBindTexture(GL_TEXTURE_2D_ARRAY, self.texture_id)
def __exit__(self, *a):
glBindTexture(GL_TEXTURE_2D_ARRAY, 0)