Source code for pi3d.util.StereoCam

from __future__ import absolute_import, division, print_function, unicode_literals

import ctypes
import numpy as np
import math

from pi3d.constants import GL_SCISSOR_TEST, GLint, GLsizei
from pi3d.Shader import Shader
from pi3d.Camera import Camera
from pi3d.shape.Sprite import Sprite
from pi3d.util.OffScreenTexture import OffScreenTexture
from pi3d.Display import Display
from pi3d import opengles

[docs]class StereoCam(object): """For creating an apparatus with two sprites to hold left and right eye views. This Class is used to hold the 3D Camera which should be used to draw the 3D objects. It also holds a 2D Camera for drawing the Sprites""" def __init__(self, shader="uv_flat", mipmap=False, separation=0.4, interlace=0): """ calls Texture.__init__ but doesn't need to set file name as texture generated from the framebuffer. Keyword Arguments: *shader* to use when drawing sprite, defaults to uv_flat. *mipmap* can be set to True with slight cost to speed, or use fxaa shader *separation* distance between the two camera positions - how wide apart the eye views are. *interlace* if interlace > 0 then the images are not taken with glScissor and must be drawn with a special interlacing shader. """ # load shader if interlace <= 0: # i.e. default side by side behaviour self.shader = Shader.create(shader) else: self.shader = Shader(vshader_source = """ precision mediump float; attribute vec3 vertex; attribute vec2 texcoord; uniform mat4 modelviewmatrix[2]; varying vec2 texcoordout; void main(void) { texcoordout = texcoord; gl_Position = modelviewmatrix[1] * vec4(vertex,1.0); } """, fshader_source = """ precision mediump float; uniform sampler2D tex0; uniform sampler2D tex1; varying vec2 texcoordout; void main(void) {{ vec4 texc0 = texture2D(tex0, texcoordout); vec4 texc1 = texture2D(tex1, texcoordout); vec2 coord = vec2(gl_FragCoord); gl_FragColor = mix(texc0, texc1, step(0.5, fract(coord.x / {:f}))); }} """.format(interlace * 2.0)) self.camera_3d = Camera() # create 3d cam first so it becomes default instance self.forMtrx = np.identity(4, dtype='float32') # initially not rotated self.position = [0.0, 0.0, 0.0] self.camera_2d = Camera(is_3d=False) self.offs = separation / 2.0 self.interlace = interlace self.textures = [] self.sprites = [] self.tex_list = [] for i in range(2): self.textures.append(OffScreenTexture(name="stereo")) ix, iy = self.textures[i].ix, self.textures[i].iy #two sprites full width but moved so that they are centred on the #left and right edges. The offset values then move the uv mapping #so the image is on the right of the left sprite and left of the #right sprite self.sprites.append(Sprite(z=20.0, w=ix, h=iy, flip=True)) if interlace <= 0: self.sprites[i].positionX(-ix/2.0 + i*ix) self.sprites[i].set_offset((i * 0.5 - 0.25, 0.0)) else: self.sprites[i].set_2d_size(w=ix, h=iy) self.textures[i].blend = True self.textures[i].mipmap = mipmap self.tex_list.append(self.textures[i]) opengles.glColorMask(1, 1, 1, 1)
[docs] def move_camera(self, position, rot, tilt, roll=0.0, absolute=True): ''' Arguments: *position* array [x,y,z] *rot, tilt, roll* rotations about y, x, z axis (yes it's not entirely logical for position to be an array and orientation three values but it's too late to change!) *absolute* if set to False then the rotations are treated as relative to the rotated frame of reference i.e. as if signals from VR headset 3 axis gyro. ''' self.camera_3d.rotate(tilt, rot, roll) self.camera_3d.position(position) self.camera_3d.absolute = absolute
[docs] def start_capture(self, side): """ after calling this method all object.draw()s will rendered to this texture and not appear on the display. *side* Either 0 or 1 to determine stereoscopic view """ self.camera_3d.reset() offs = -self.offs if side == 0 else self.offs self.camera_3d.offset([offs, 0.0, 0.0]) #self.camera_3d.mtrx =, self.camera_3d.mtrx) #self.camera_3d.position(self.position) tex = self.textures[side] tex._start() if self.interlace <= 0: xx = tex.ix / 4.0 # draw the middle only - half width yy = 0 ww = tex.ix / 2.0 hh = tex.iy opengles.glEnable(GL_SCISSOR_TEST) opengles.glScissor(GLint(int(xx)), GLint(int(yy)), GLsizei(int(ww)), GLsizei(int(hh)))
[docs] def end_capture(self, side): """ stop capturing to texture and resume normal rendering to default """ self.textures[side]._end() if self.interlace <= 0: opengles.glDisable(GL_SCISSOR_TEST)
[docs] def draw(self): """ draw the shape using the saved texture """ if self.interlace <= 0: for i in range(2): self.sprites[i].draw(self.shader, [self.tex_list[i].color], 0.0, 0.0, self.camera_2d) else: self.sprites[0].draw(self.shader, [t.color for t in self.tex_list], 0.0, 0.0, self.camera_2d)
[docs] def get_direction(self): return self.camera_3d.get_direction()