"""Low-level graphics rendering and abstractions. This module provides efficient abstractions over OpenGL objects, such as Shaders and Buffers. It also provides classes for highly performant batched rendering and grouping. See the :ref:`guide_graphics` for details on how to use this graphics API. Batches and groups ================== Developers can make use of :py:class:`~pyglet.graphics.Batch` and :py:class:`~pyglet.graphics.Group` objects to improve performance when rendering a large number of objects. The :py:class:`~pyglet.sprite.Sprite`, :py:func:`~pyglet.text.Label`, :py:func:`~pyglet.text.layout.TextLayout`, and other classes all accept a ``batch`` and ``group`` parameter in their constructors. A Batch manages a set of objects that will be drawn all at once, and a Group can be used to set OpenGL state and further sort the draw operation. The following example creates a batch, adds two sprites to the batch, and then draws the entire batch:: batch = pyglet.graphics.Batch() car = pyglet.sprite.Sprite(car_image, batch=batch) boat = pyglet.sprite.Sprite(boat_image, batch=batch) def on_draw(): batch.draw() Drawing a complete Batch is much faster than drawing the items in the batch individually, especially when those items belong to a common group. Groups describe the OpenGL state required for an item. This is for the most part managed by the sprite, text, and other classes, however you can also use custom groups to ensure items are drawn in a particular order. For example, the following example adds a background sprite which is guaranteed to be drawn before the car and the boat:: batch = pyglet.graphics.Batch() background = pyglet.graphics.Group(order=0) foreground = pyglet.graphics.Group(order=1) background = pyglet.sprite.Sprite(background_image, batch=batch, group=background) car = pyglet.sprite.Sprite(car_image, batch=batch, group=foreground) boat = pyglet.sprite.Sprite(boat_image, batch=batch, group=foreground) def on_draw(): batch.draw() It's preferable to manage pyglet objects within as few batches as possible. If the drawing of sprites or text objects need to be interleaved with other drawing that does not use the graphics API, multiple batches will be required. """ import ctypes import weakref import pyglet from pyglet.gl import * from pyglet.graphics import shader, vertexdomain from pyglet.graphics.vertexarray import VertexArray from pyglet.graphics.vertexbuffer import BufferObject _debug_graphics_batch = pyglet.options['debug_graphics_batch'] def draw(size, mode, **data): """Draw a primitive immediately. :warning: This function is deprecated as of 2.0.4, and will be removed in the next release. :Parameters: `size` : int Number of vertices given `mode` : gl primitive type OpenGL drawing mode, e.g. ``GL_TRIANGLES``, avoiding quotes. `**data` : keyword arguments for passing vertex attribute data. The keyword should be the vertex attribute name, and the argument should be a tuple of (format, data). For example: `position=('f', array)` """ # Create and bind a throwaway VAO vao_id = GLuint() glGenVertexArrays(1, vao_id) glBindVertexArray(vao_id) # Activate shader program: program = get_default_shader() program.use() buffers = [] for name, (fmt, array) in data.items(): location = program.attributes[name]['location'] count = program.attributes[name]['count'] gl_type = vertexdomain._gl_types[fmt[0]] normalize = 'n' in fmt attribute = shader.Attribute(name, location, count, gl_type, normalize) assert size == len(array) // attribute.count, 'Data for %s is incorrect length' % fmt buffer = BufferObject(size * attribute.stride) attribute.set_region(buffer, 0, size, array) attribute.enable() attribute.set_pointer(buffer.ptr) buffers.append(buffer) # Don't garbage collect it. glDrawArrays(mode, 0, size) # Deactivate shader program: program.stop() # Discard everything after drawing: del buffers glBindVertexArray(0) glDeleteVertexArrays(1, vao_id) def draw_indexed(size, mode, indices, **data): """Draw a primitive with indexed vertices immediately. :warning: This function is deprecated as of 2.0.4, and will be removed in the next release. :Parameters: `size` : int Number of vertices given `mode` : int OpenGL drawing mode, e.g. ``GL_TRIANGLES`` `indices` : sequence of int Sequence of integers giving indices into the vertex list. `**data` : keyword arguments for passing vertex attribute data. The keyword should be the vertex attribute name, and the argument should be a tuple of (format, data). For example: `position=('f', array)` """ # Create and bind a throwaway VAO vao_id = GLuint() glGenVertexArrays(1, vao_id) glBindVertexArray(vao_id) # Activate shader program: program = get_default_shader() program.use() buffers = [] for name, (fmt, array) in data.items(): location = program.attributes[name]['location'] count = program.attributes[name]['count'] gl_type = vertexdomain._gl_types[fmt[0]] normalize = 'n' in fmt attribute = shader.Attribute(name, location, count, gl_type, normalize) assert size == len(array) // attribute.count, 'Data for %s is incorrect length' % fmt buffer = BufferObject(size * attribute.stride) attribute.set_region(buffer, 0, size, array) attribute.enable() attribute.set_pointer(buffer.ptr) buffers.append(buffer) if size <= 0xff: index_type = GL_UNSIGNED_BYTE index_c_type = ctypes.c_ubyte elif size <= 0xffff: index_type = GL_UNSIGNED_SHORT index_c_type = ctypes.c_ushort else: index_type = GL_UNSIGNED_INT index_c_type = ctypes.c_uint # With GL 3.3 vertex arrays indices needs to be in a buffer # bound to the ELEMENT_ARRAY slot index_array = (index_c_type * len(indices))(*indices) index_buffer = BufferObject(ctypes.sizeof(index_array)) index_buffer.set_data(index_array) index_buffer.bind_to_index_buffer() glDrawElements(mode, len(indices), index_type, 0) glFlush() # Deactivate shader program: program.stop() # Discard everything after drawing: del buffers del index_buffer glBindVertexArray(0) glDeleteVertexArrays(1, vao_id) # Default Shader source: _vertex_source = """#version 330 core in vec3 position; in vec4 colors; in vec3 tex_coords; out vec4 vertex_colors; out vec3 texture_coords; uniform WindowBlock { mat4 projection; mat4 view; } window; void main() { gl_Position = window.projection * window.view * vec4(position, 1.0); vertex_colors = colors; texture_coords = tex_coords; } """ _fragment_source = """#version 330 core in vec4 vertex_colors; in vec3 texture_coords; out vec4 final_colors; uniform sampler2D our_texture; void main() { final_colors = texture(our_texture, texture_coords.xy) + vertex_colors; } """ def get_default_batch(): try: return pyglet.gl.current_context.pyglet_graphics_default_batch except AttributeError: pyglet.gl.current_context.pyglet_graphics_default_batch = Batch() return pyglet.gl.current_context.pyglet_graphics_default_batch def get_default_group(): try: return pyglet.gl.current_context.pyglet_graphics_default_group except AttributeError: pyglet.gl.current_context.pyglet_graphics_default_group = ShaderGroup(get_default_shader()) return pyglet.gl.current_context.pyglet_graphics_default_group def get_default_shader(): try: return pyglet.gl.current_context.pyglet_graphics_default_shader except AttributeError: _default_vert_shader = pyglet.graphics.shader.Shader(_vertex_source, 'vertex') _default_frag_shader = pyglet.graphics.shader.Shader(_fragment_source, 'fragment') default_shader_program = pyglet.graphics.shader.ShaderProgram(_default_vert_shader, _default_frag_shader) pyglet.gl.current_context.pyglet_graphics_default_shader = default_shader_program return pyglet.gl.current_context.pyglet_graphics_default_shader class Batch: """Manage a collection of vertex lists for batched rendering. Vertex lists are added to a :py:class:`~pyglet.graphics.Batch` using the `add` and `add_indexed` methods. An optional group can be specified along with the vertex list, which gives the OpenGL state required for its rendering. Vertex lists with shared mode and group are allocated into adjacent areas of memory and sent to the graphics card in a single operation. Call `VertexList.delete` to remove a vertex list from the batch. """ def __init__(self): """Create a graphics batch.""" # Mapping to find domain. # group -> (attributes, mode, indexed) -> domain self.group_map = {} # Mapping of group to list of children. self.group_children = {} # List of top-level groups self.top_groups = [] self._draw_list = [] self._draw_list_dirty = False self._context = pyglet.gl.current_context def invalidate(self): """Force the batch to update the draw list. This method can be used to force the batch to re-compute the draw list when the ordering of groups has changed. .. versionadded:: 1.2 """ self._draw_list_dirty = True def migrate(self, vertex_list, mode, group, batch): """Migrate a vertex list to another batch and/or group. `vertex_list` and `mode` together identify the vertex list to migrate. `group` and `batch` are new owners of the vertex list after migration. The results are undefined if `mode` is not correct or if `vertex_list` does not belong to this batch (they are not checked and will not necessarily throw an exception immediately). `batch` can remain unchanged if only a group change is desired. :Parameters: `vertex_list` : `~pyglet.graphics.vertexdomain.VertexList` A vertex list currently belonging to this batch. `mode` : int The current GL drawing mode of the vertex list. `group` : `~pyglet.graphics.Group` The new group to migrate to. `batch` : `~pyglet.graphics.Batch` The batch to migrate to (or the current batch). """ program = vertex_list.domain.program attributes = vertex_list.domain.attribute_meta if isinstance(vertex_list, vertexdomain.IndexedVertexList): domain = batch.get_domain(True, mode, group, program, attributes) else: domain = batch.get_domain(False, mode, group, program, attributes) vertex_list.migrate(domain) def get_domain(self, indexed, mode, group, program, attributes): if group is None: group = ShaderGroup(program=program) # Batch group if group not in self.group_map: self._add_group(group) # Find domain given formats, indices and mode domain_map = self.group_map[group] key = (indexed, mode, program, str(attributes)) try: domain = domain_map[key] except KeyError: # Create domain if indexed: domain = vertexdomain.IndexedVertexDomain(program, attributes) else: domain = vertexdomain.VertexDomain(program, attributes) domain_map[key] = domain self._draw_list_dirty = True return domain def _add_group(self, group): self.group_map[group] = {} if group.parent is None: self.top_groups.append(group) else: if group.parent not in self.group_map: self._add_group(group.parent) if group.parent not in self.group_children: self.group_children[group.parent] = [] self.group_children[group.parent].append(group) group._assigned_batches.add(self) self._draw_list_dirty = True def _update_draw_list(self): """Visit group tree in preorder and create a list of bound methods to call. """ def visit(group): draw_list = [] # Draw domains using this group domain_map = self.group_map[group] for (formats, mode, indexed, program_id), domain in list(domain_map.items()): # Remove unused domains from batch if domain.is_empty: del domain_map[(formats, mode, indexed, program_id)] continue draw_list.append((lambda d, m: lambda: d.draw(m))(domain, mode)) # Sort and visit child groups of this group children = self.group_children.get(group) if children: children.sort() for child in list(children): if child.visible: draw_list.extend(visit(child)) if children or domain_map: return [group.set_state] + draw_list + [group.unset_state] else: # Remove unused group from batch del self.group_map[group] group._assigned_batches.remove(self) if group.parent: self.group_children[group.parent].remove(group) try: del self.group_children[group] except KeyError: pass try: self.top_groups.remove(group) except ValueError: pass return [] self._draw_list = [] self.top_groups.sort() for group in list(self.top_groups): if group.visible: self._draw_list.extend(visit(group)) self._draw_list_dirty = False if _debug_graphics_batch: self._dump_draw_list() def _dump_draw_list(self): def dump(group, indent=''): print(indent, 'Begin group', group) domain_map = self.group_map[group] for _, domain in domain_map.items(): print(indent, ' ', domain) for start, size in zip(*domain.allocator.get_allocated_regions()): print(indent, ' ', 'Region %d size %d:' % (start, size)) for key, attribute in domain.attribute_names.items(): print(indent, ' ', end=' ') try: region = attribute.get_region(attribute.buffer, start, size) print(key, region.array[:]) except: print(key, '(unmappable)') for child in self.group_children.get(group, ()): dump(child, indent + ' ') print(indent, 'End group', group) print('Draw list for %r:' % self) for group in self.top_groups: dump(group) def draw(self): """Draw the batch.""" if self._draw_list_dirty: self._update_draw_list() for func in self._draw_list: func() def draw_subset(self, vertex_lists): """Draw only some vertex lists in the batch. The use of this method is highly discouraged, as it is quite inefficient. Usually an application can be redesigned so that batches can always be drawn in their entirety, using `draw`. The given vertex lists must belong to this batch; behaviour is undefined if this condition is not met. :Parameters: `vertex_lists` : sequence of `VertexList` or `IndexedVertexList` Vertex lists to draw. """ # Horrendously inefficient. def visit(group): group.set_state() # Draw domains using this group domain_map = self.group_map[group] for (_, mode, _, _), domain in domain_map.items(): for alist in vertex_lists: if alist.domain is domain: alist.draw(mode) # Sort and visit child groups of this group children = self.group_children.get(group) if children: children.sort() for child in children: if child.visible: visit(child) group.unset_state() self.top_groups.sort() for group in self.top_groups: if group.visible: visit(group) class Group: """Group of common OpenGL state. Before a VertexList is rendered, its Group's OpenGL state is set. This includes binding textures, shaders, or setting any other parameters. """ def __init__(self, order=0, parent=None): """Create a Group. :Parameters: `order` : int Set the order to render above or below other Groups. `parent` : `~pyglet.graphics.Group` Group to contain this Group; its state will be set before this Group's state. :Ivariables: `visible` : bool Determines whether this Group is visible in any of the Batches it is assigned to. If False, objects in this Group will not be rendered. `batches` : list Read Only. A list of which Batches this Group is a part of. """ self._order = order self.parent = parent self._visible = True self._assigned_batches = weakref.WeakSet() @property def order(self): return self._order @property def visible(self): return self._visible @visible.setter def visible(self, value): self._visible = value for batch in self._assigned_batches: batch.invalidate() @property def batches(self): return [batch for batch in self._assigned_batches] def __lt__(self, other): return self._order < other.order def __eq__(self, other): return (self.__class__ is other.__class__ and self._order == other.order and self.parent == other.parent) def __hash__(self): return hash((self._order, self.parent)) def __repr__(self): return "{}(order={})".format(self.__class__.__name__, self._order) def set_state(self): """Apply the OpenGL state change. The default implementation does nothing.""" pass def unset_state(self): """Repeal the OpenGL state change. The default implementation does nothing.""" pass def set_state_recursive(self): """Set this group and its ancestry. Call this method if you are using a group in isolation: the parent groups will be called in top-down order, with this class's `set` being called last. """ if self.parent: self.parent.set_state_recursive() self.set_state() def unset_state_recursive(self): """Unset this group and its ancestry. The inverse of `set_state_recursive`. """ self.unset_state() if self.parent: self.parent.unset_state_recursive() # Example Groups. class ShaderGroup(Group): """A group that enables and binds a ShaderProgram. """ def __init__(self, program, order=0, parent=None): super().__init__(order, parent) self.program = program def set_state(self): self.program.use() def unset_state(self): self.program.stop() def __eq__(self, other): return (self.__class__ is other.__class__ and self._order == other.order and self.program == other.program and self.parent == other.parent) def __hash__(self): return hash((self._order, self.parent, self.program)) class TextureGroup(Group): """A group that enables and binds a texture. TextureGroups are equal if their textures' targets and names are equal. """ def __init__(self, texture, order=0, parent=None): """Create a texture group. :Parameters: `texture` : `~pyglet.image.Texture` Texture to bind. `order` : int Change the order to render above or below other Groups. `parent` : `~pyglet.graphics.Group` Parent group. """ super().__init__(order, parent) self.texture = texture def set_state(self): glActiveTexture(GL_TEXTURE0) glBindTexture(self.texture.target, self.texture.id) def __hash__(self): return hash((self.texture.target, self.texture.id, self.order, self.parent)) def __eq__(self, other): return (self.__class__ is other.__class__ and self.texture.target == other.texture.target and self.texture.id == other.texture.id and self.order == other.order and self.parent == other.parent) def __repr__(self): return '%s(id=%d)' % (self.__class__.__name__, self.texture.id)