Source code for silx.gui._glutils.FramebufferTexture

# coding: utf-8
# /*##########################################################################
#
# Copyright (c) 2014-2020 European Synchrotron Radiation Facility
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
#
# ###########################################################################*/
"""Association of a texture and a framebuffer object for off-screen rendering.
"""

__authors__ = ["T. Vincent"]
__license__ = "MIT"
__date__ = "25/07/2016"


import logging

from . import gl
from .Texture import Texture


_logger = logging.getLogger(__name__)


[docs]class FramebufferTexture(object): """Framebuffer with a texture. Aimed at off-screen rendering to texture. :param internalFormat: OpenGL texture internal format :param shape: Shape (height, width) of the framebuffer and texture :type shape: 2-tuple of int :param stencilFormat: Stencil renderbuffer format :param depthFormat: Depth renderbuffer format :param kwargs: Extra arguments for :class:`Texture` constructor """ _PACKED_FORMAT = gl.GL_DEPTH24_STENCIL8, gl.GL_DEPTH_STENCIL def __init__(self, internalFormat, shape, stencilFormat=gl.GL_DEPTH24_STENCIL8, depthFormat=gl.GL_DEPTH24_STENCIL8, **kwargs): self._texture = Texture(internalFormat, shape=shape, **kwargs) self._texture.prepare() self._previousFramebuffer = 0 # Used by with statement self._name = gl.glGenFramebuffers(1) with self: # Bind FBO # Attachments gl.glFramebufferTexture2D(gl.GL_FRAMEBUFFER, gl.GL_COLOR_ATTACHMENT0, gl.GL_TEXTURE_2D, self._texture.name, 0) height, width = self._texture.shape if stencilFormat is not None: self._stencilId = gl.glGenRenderbuffers(1) gl.glBindRenderbuffer(gl.GL_RENDERBUFFER, self._stencilId) gl.glRenderbufferStorage(gl.GL_RENDERBUFFER, stencilFormat, width, height) gl.glFramebufferRenderbuffer(gl.GL_FRAMEBUFFER, gl.GL_STENCIL_ATTACHMENT, gl.GL_RENDERBUFFER, self._stencilId) else: self._stencilId = None if depthFormat is not None: if self._stencilId and depthFormat in self._PACKED_FORMAT: self._depthId = self._stencilId else: self._depthId = gl.glGenRenderbuffers(1) gl.glBindRenderbuffer(gl.GL_RENDERBUFFER, self._depthId) gl.glRenderbufferStorage(gl.GL_RENDERBUFFER, depthFormat, width, height) gl.glFramebufferRenderbuffer(gl.GL_FRAMEBUFFER, gl.GL_DEPTH_ATTACHMENT, gl.GL_RENDERBUFFER, self._depthId) else: self._depthId = None status = gl.glCheckFramebufferStatus(gl.GL_FRAMEBUFFER) if status != gl.GL_FRAMEBUFFER_COMPLETE: _logger.error( "OpenGL framebuffer initialization not complete, display may fail (error %d)", status) @property def shape(self): """Shape of the framebuffer (height, width)""" return self._texture.shape @property def texture(self): """The texture this framebuffer is rendering to. The life-cycle of the texture is managed by this object""" return self._texture @property def name(self): """OpenGL name of the framebuffer""" if self._name is not None: return self._name else: raise RuntimeError("No OpenGL framebuffer resource, \ discard has already been called")
[docs] def bind(self): """Bind this framebuffer for rendering""" gl.glBindFramebuffer(gl.GL_FRAMEBUFFER, self.name)
# with statement def __enter__(self): self._previousFramebuffer = gl.glGetInteger(gl.GL_FRAMEBUFFER_BINDING) self.bind() def __exit__(self, exctype, excvalue, traceback): gl.glBindFramebuffer(gl.GL_FRAMEBUFFER, self._previousFramebuffer) self._previousFramebuffer = None
[docs] def discard(self): """Delete associated OpenGL resources including texture""" if self._name is not None: gl.glDeleteFramebuffers(self._name) self._name = None if self._stencilId is not None: gl.glDeleteRenderbuffers(self._stencilId) if self._stencilId == self._depthId: self._depthId = None self._stencilId = None if self._depthId is not None: gl.glDeleteRenderbuffers(self._depthId) self._depthId = None self._texture.discard() # Also discard the texture else: _logger.warning("Discard has already been called")