import itertools
import numpy as np
from ... import mesh
from .internal import GLPrimitive, GLShapeDecorator
from ... import draw
from ..internal import ShapeAttribute
from ..Scene import DEFAULT_DIRECTIONAL_LIGHTS
[docs]@GLShapeDecorator
class Spheres(draw.Spheres, GLPrimitive):
__doc__ = draw.Spheres.__doc__
shaders = {}
shaders['vertex'] = """
uniform mat4 camera;
uniform vec4 rotation;
uniform vec3 translation;
uniform int transparency_mode;
attribute vec4 color;
attribute vec3 position;
attribute vec2 image;
attribute float radius;
attribute vec4 shape_id;
varying vec4 v_color;
varying vec3 v_position;
varying vec2 v_image;
varying float v_radius;
varying float v_depth;
varying vec4 v_shape_id;
vec3 rotate(vec3 point, vec4 quat)
{
vec3 result = (quat.x*quat.x - dot(quat.yzw, quat.yzw))*point;
result += 2.0*quat.x*cross(quat.yzw, point);
result += 2.0*dot(quat.yzw, point)*quat.yzw;
return result;
}
void main()
{
vec3 vertexPos = position;
vec2 localPos = image*radius;
vertexPos = rotate(vertexPos, rotation) + vec3(localPos, 0.0) + translation;
vec4 screenPosition = camera * vec4(vertexPos, 1.0);
int should_discard = 0;
should_discard += int(transparency_mode < 0 && color.a < 1.0);
should_discard += int(transparency_mode > 0 && color.a >= 1.0);
if(should_discard > 0)
screenPosition = vec4(2.0, 2.0, 2.0, 2.0);
// transform to screen coordinates
gl_Position = screenPosition;
v_color = color;
v_image = localPos;
v_radius = radius;
v_position = vertexPos;
v_depth = vertexPos.z;
v_shape_id = shape_id;
}
"""
shaders['fragment'] = """
#ifdef GL_ES
precision highp float;
#endif
// base light level
uniform float ambientLight;
// (x, y, z) direction*intensity
uniform vec3 diffuseLight[NUM_DIFFUSELIGHT];
uniform int transparency_mode;
uniform mat4 camera;
uniform float light_levels;
uniform float outline;
varying vec4 v_color;
varying vec2 v_image;
varying float v_radius;
varying float v_depth;
void main()
{
float rsq = dot(v_image, v_image);
float Rsq = v_radius*v_radius;
float r = sqrt(rsq);
float lambda1 = 1.0;
if(outline > 1e-6)
{
lambda1 = (v_radius - r)/outline;
lambda1 *= lambda1;
lambda1 *= lambda1;
lambda1 *= lambda1;
lambda1 *= lambda1;
lambda1 = min(lambda1, 1.0);
}
if(r > v_radius) discard;
vec3 r_local = vec3(v_image.xy, sqrt(Rsq - rsq));
vec3 normal = normalize(r_local);
float light = ambientLight;
for(int i = 0; i < NUM_DIFFUSELIGHT; ++i)
light += max(0.0, -dot(normal, diffuseLight[i]));
if(light_levels > 0.0)
{
light *= light_levels;
light = floor(light);
light /= light_levels;
}
vec4 color = vec4(v_color.xyz*lambda1*light, v_color.w);
#ifndef WEBGL
float depth = v_depth + r_local.z;
gl_FragDepth = 0.5*(camera[2][2]*depth + camera[3][2] +
camera[2][3]*depth + camera[3][3])/(camera[2][3]*depth + camera[3][3]);
#endif
float z = abs(v_depth);
float alpha = color.a;
float weight = alpha*max(3e3*pow(
(1.0 - gl_FragCoord.z), 3.0), 1e-2);
if(transparency_mode < 1)
gl_FragColor = color;
else if(transparency_mode == 1)
gl_FragColor = vec4(color.rgb*alpha, alpha)*weight;
else
gl_FragColor = vec4(alpha);
}
"""
shaders['fragment_plane'] = """
// base light level
uniform mat4 camera;
uniform float render_positions = 0.0;
varying vec3 v_position;
varying vec2 v_image;
varying float v_radius;
varying float v_depth;
void main()
{
float rsq = dot(v_image, v_image);
float Rsq = v_radius*v_radius;
if(rsq > Rsq)
discard;
vec3 r_local = vec3(v_image.xy, sqrt(Rsq - rsq));
vec3 normal = normalize(r_local);
#ifndef WEBGL
float depth = v_depth + r_local.z;
gl_FragDepth = 0.5*(camera[2][2]*depth + camera[3][2] +
camera[2][3]*depth + camera[3][3])/(camera[2][3]*depth + camera[3][3]);
#endif
if(render_positions > 0.5)
gl_FragColor = vec4(gl_FragCoord.xyz, 1.0);
else if(render_positions < -0.5)
gl_FragColor = 0.5 + 0.5*vec4(normal.xyz, 1.0);
else // Store the plane equation as a color
gl_FragColor = vec4(normal, dot(normal, v_position.xyz));
}
"""
shaders['fragment_pick'] = """
uniform mat4 camera;
uniform vec4 pick_prim_index;
varying vec3 v_position;
varying vec2 v_image;
varying float v_radius;
varying float v_depth;
varying vec4 v_shape_id;
void main()
{
float rsq = dot(v_image, v_image);
float Rsq = v_radius*v_radius;
if(rsq > Rsq)
discard;
vec3 r_local = vec3(v_image.xy, sqrt(Rsq - rsq));
vec3 normal = normalize(r_local);
#ifndef WEBGL
float depth = v_depth + r_local.z;
gl_FragDepth = 0.5*(camera[2][2]*depth + camera[3][2] +
camera[2][3]*depth + camera[3][3])/(camera[2][3]*depth + camera[3][3]);
#endif
gl_FragColor = pick_prim_index + v_shape_id;
}
"""
_vertex_attribute_names = ['shape_id', 'position', 'color', 'radius', 'image']
_GL_UNIFORMS = list(itertools.starmap(ShapeAttribute, [
('camera', np.float32, np.eye(4), 2, False,
'Internal: 4x4 Camera matrix for world projection'),
('ambientLight', np.float32, .25, 0, False,
'Internal: Ambient (minimum) light level for all surfaces'),
('diffuseLight[]', np.float32, DEFAULT_DIRECTIONAL_LIGHTS, 2, False,
'Internal: Diffuse light direction*magnitude'),
('rotation', np.float32, (1, 0, 0, 0), 1, False,
'Internal: Rotation to be applied to each scene as a quaternion'),
('translation', np.float32, (0, 0, 0), 1, False,
'Internal: Translation to be applied to the scene'),
('transparency_mode', np.int32, 0, 0, False,
'Internal: Transparency stage (<0: opaque, 0: all, 1: '
'translucency stage 1, 2: translucency stage 2)'),
('light_levels', np.float32, 0, 0, False,
'Number of light levels to quantize to (0: disable)'),
('outline', np.float32, 0, 0, False,
'Outline for all particles')
]))
def __init__(self, *args, **kwargs):
GLPrimitive.__init__(self)
draw.Spheres.__init__(self, *args, **kwargs)
def update_arrays(self):
try:
for name in self._dirty_attributes:
self._gl_vertex_arrays[name][:] = self._attributes[name]
self._dirty_vertex_attribs.add(name)
except (ValueError, KeyError):
# vertices for an equilateral triangle
triangle = np.array([[2, 0],
[-1, np.sqrt(3)],
[-1, -np.sqrt(3)]], dtype=np.float32)*1.01
shape_ids = np.arange(len(self), dtype=np.uint32).view(np.uint8).reshape((-1, 4))
shape_ids = shape_ids.astype(np.float32)/255
vertex_arrays = mesh.unfoldProperties(
[shape_ids, self.positions, self.colors, self.radii.reshape((-1, 1))],
[triangle])
unfolded_shape = vertex_arrays[0].shape[:-1]
indices = (np.arange(unfolded_shape[0])[:, np.newaxis, np.newaxis]*unfolded_shape[1] +
np.array([[0, 1, 2]], dtype=np.uint32))
indices = indices.reshape((-1, 3))
self._finalize_array_updates(indices, vertex_arrays)
self._dirty_attributes.clear()