def create_line(start_x: float,
start_y: float,
end_x: float,
end_y: float,
color: Color,
line_width: float = 1) -> Shape:
"""
Create a line to be rendered later. This works faster than draw_line because
the vertexes are only loaded to the graphics card once, rather than each frame.
"""
program = shader.program(
vertex_shader='''
#version 330
uniform mat4 Projection;
in vec2 in_vert;
in vec4 in_color;
out vec4 v_color;
void main() {
gl_Position = Projection * vec4(in_vert, 0.0, 1.0);
v_color = in_color;
}
''',
fragment_shader='''
#version 330
in vec4 v_color;
out vec4 f_color;
void main() {
f_color = v_color;
}
''',
)
buffer_type = np.dtype([('vertex', '2f4'), ('color', '4B')])
data = np.zeros(2, dtype=buffer_type)
data['vertex'] = (start_x, start_y), (end_x, end_y)
data['color'] = get_four_byte_color(color)
vbo = shader.buffer(data.tobytes())
vao_content = [
shader.BufferDescription(vbo,
'2f 4B', ('in_vert', 'in_color'),
normalized=['in_color'])
]
vao = shader.vertex_array(program, vao_content)
with vao:
program['Projection'] = get_projection().flatten()
shape = Shape()
shape.vao = vao
shape.vbo = vbo
shape.program = program
shape.mode = gl.GL_LINE_STRIP
shape.line_width = line_width
return shape
def create_line_generic_with_colors(point_list: PointList,
color_list: Iterable[Color],
shape_mode: int,
line_width: float=1) -> Shape:
"""
This function is used by ``create_line_strip`` and ``create_line_loop``,
just changing the OpenGL type for the line drawing.
"""
program = shader.program(
vertex_shader='''
#version 330
uniform mat4 Projection;
in vec2 in_vert;
in vec4 in_color;
out vec4 v_color;
void main() {
gl_Position = Projection * vec4(in_vert, 0.0, 1.0);
v_color = in_color;
}
''',
fragment_shader='''
#version 330
in vec4 v_color;
out vec4 f_color;
void main() {
f_color = v_color;
}
''',
)
buffer_type = np.dtype([('vertex', '2f4'), ('color', '4B')])
data = np.zeros(len(point_list), dtype=buffer_type)
data['vertex'] = point_list
data['color'] = [get_four_byte_color(color) for color in color_list]
vbo = shader.buffer(data.tobytes())
vao_content = [
shader.BufferDescription(
vbo,
'2f 4B',
('in_vert', 'in_color'),
normalized=['in_color']
)
]
vao = shader.vertex_array(program, vao_content)
with vao:
program['Projection'] = get_projection().flatten()
shape = Shape()
shape.vao = vao
shape.vbo = vbo
shape.program = program
shape.mode = shape_mode
shape.line_width = line_width
return shape
def _refresh_shape(self, group):
# Create a buffer large enough to hold all the shapes buffers
batch = self.batches[group]
total_vbo_bytes = sum(s.vbo.size for s in batch.items)
vbo = shader.Buffer.create_with_size(total_vbo_bytes)
offset = 0
gl.glBindBuffer(gl.GL_COPY_WRITE_BUFFER, vbo.buffer_id)
# Copy all the shapes buffer in our own vbo
for shape in batch.items:
gl.glBindBuffer(gl.GL_COPY_READ_BUFFER, shape.vbo.buffer_id)
gl.glCopyBufferSubData(
gl.GL_COPY_READ_BUFFER,
gl.GL_COPY_WRITE_BUFFER,
gl.GLintptr(0),
gl.GLintptr(offset),
shape.vbo.size)
offset += shape.vbo.size
# Create an index buffer object. It should count starting from 0. We need to
# use a reset_idx to indicate that a new shape will start.
reset_idx = 2 ** 32 - 1
indices = []
counter = itertools.count()
for shape in batch.items:
indices.extend(itertools.islice(counter, shape.vao.num_vertices))
indices.append(reset_idx)
del indices[-1]
indices = np.array(indices)
ibo = shader.Buffer(indices.astype('i4').tobytes())
vao_content = [
shader.BufferDescription(
vbo,
'2f 4B',
('in_vert', 'in_color'),
normalized=['in_color']
)
]
vao = shader.vertex_array(self.program, vao_content, ibo)
with self.program:
self.program['Projection'] = get_projection().flatten()
self.program['Position'] = [self.center_x, self.center_y]
self.program['Angle'] = self.angle
batch.shape.vao = vao
batch.shape.vbo = vbo
batch.shape.ibo = ibo
batch.shape.program = self.program
mode, line_width = group
batch.shape.mode = mode
batch.shape.line_width = line_width
