rendering.py

"""
A 2D rendering framework borrowed from OpenAI gym
"""

from __future__ import division
import os
import six
import sys
import pyglet
import numpy as np
from numpy.linalg import norm

from pyglet.gl import *

import simulator_config

if "Apple" in sys.version:
    if 'DYLD_FALLBACK_LIBRARY_PATH' in os.environ:
        os.environ['DYLD_FALLBACK_LIBRARY_PATH'] += ':/usr/lib'
        # (JDS 2016/04/15): avoid bug on Anaconda 2.3.0 / Yosemite

import math
import numpy as np
from scipy.spatial.distance import cdist


RAD2DEG = 57.29577951308232

def get_display(spec):
    """Convert a display specification (such as :0) into an actual Display
    object.
    Pyglet only supports multiple Displays on Linux.
    """
    if spec is None:
        return None
    elif isinstance(spec, six.string_types):
        return pyglet.canvas.Display(spec)
    else:
        raise ValueError('Invalid display specification: {}. (Must be a string like :0 or None.)'.format(spec))


class Viewer(object):
    def __init__(self, width, height, display=None):
        display = get_display(display)

        self.width = width
        self.height = height
        self.window = pyglet.window.Window(width=width, height=height, display=display)
        self.window.on_close = self.window_closed_by_user
        self.geoms = []
        self.onetime_geoms = []
        self.transform = Transform()

        glEnable(GL_BLEND)
        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)

    def close(self):
        self.window.close()

    def window_closed_by_user(self):
        self.close()

    def set_bounds(self, left, right, bottom, top):
        assert right > left and top > bottom
        scalex = self.width/(right-left)
        scaley = self.height/(top-bottom)
        self.transform = Transform(
            translation=(-left*scalex, -bottom*scaley),
            scale=(scalex, scaley))

    def add_geom(self, geom):
        self.geoms.append(geom)

    def add_onetime(self, geom):
        self.onetime_geoms.append(geom)

    def render(self, return_rgb_array=False):
        glClearColor(1,1,1,1)
        self.window.clear()
        self.window.switch_to()
        self.window.dispatch_events()
        self.transform.enable()
        for geom in self.geoms:
            geom.render()
        for geom in self.onetime_geoms:
            geom.render()
        self.transform.disable()
        arr = None
        if return_rgb_array:
            buffer = pyglet.image.get_buffer_manager().get_color_buffer()
            image_data = buffer.get_image_data()
            arr = np.fromstring(image_data.data, dtype=np.uint8, sep='')
            # In https://github.com/openai/gym-http-api/issues/2, we
            # discovered that someone using Xmonad on Arch was having
            # a window of size 598 x 398, though a 600 x 400 window
            # was requested. (Guess Xmonad was preserving a pixel for
            # the boundary.) So we use the buffer height/width rather
            # than the requested one.
            arr = arr.reshape(buffer.height, buffer.width, 4)
            arr = arr[::-1,:,0:3]
        self.window.flip()
        self.onetime_geoms = []
        return arr

    # Convenience
    def draw_circle(self, radius=10, res=30, filled=True, **attrs):
        geom = make_circle(radius=radius, res=res, filled=filled)
        _add_attrs(geom, attrs)
        self.add_onetime(geom)
        return geom

    def draw_polygon(self, v, filled=True, **attrs):
        geom = make_polygon(v=v, filled=filled)
        _add_attrs(geom, attrs)
        self.add_onetime(geom)
        return geom

    def draw_polyline(self, v, **attrs):
        geom = make_polyline(v=v)
        _add_attrs(geom, attrs)
        self.add_onetime(geom)
        return geom

    def draw_line(self, start, end, **attrs):
        geom = Line(start, end)
        _add_attrs(geom, attrs)
        self.add_onetime(geom)
        return geom

    def get_array(self):
        self.window.flip()
        image_data = pyglet.image.get_buffer_manager().get_color_buffer().get_image_data()
        self.window.flip()
        arr = np.fromstring(image_data.data, dtype=np.uint8, sep='')
        arr = arr.reshape(self.height, self.width, 4)
        return arr[::-1,:,0:3]


def _add_attrs(geom, attrs):
    if "color" in attrs:
        geom.set_color(*attrs["color"])
    if "linewidth" in attrs:
        geom.set_linewidth(attrs["linewidth"])


class Geom(object):
    def __init__(self):
        self._color=Color((0, 0, 0, 1.0))
        self.attrs = [self._color]
    def render(self):
        for attr in reversed(self.attrs):
            attr.enable()
        self.render1()
        for attr in self.attrs:
            attr.disable()
    def render1(self):
        raise NotImplementedError
    def add_attr(self, attr):
        self.attrs.append(attr)
    def set_color_rgb(self, vec):
        assert len(vec) == 3
        r, g, b = vec
        self._color.vec4 = (r, g, b, 1)

    def set_color_rgba(self, vec):
        r, g, b, a= vec
        self._color.vec4 = (r, g, b, a)

    def set_color(self, r, g, b):
        self._color.vec4 = (r, g, b, 1)


class Attr(object):
    def enable(self):
        raise NotImplementedError
    def disable(self):
        pass


class Transform(Attr):
    def __init__(self, translation=(0.0, 0.0), rotation=0.0, scale=(1,1)):
        self.set_translation(*translation)
        self.set_rotation(rotation)
        self.set_scale(*scale)
    def enable(self):
        glPushMatrix()
        glTranslatef(self.translation[0], self.translation[1], 0) # translate to GL loc ppint
        glRotatef(RAD2DEG * self.rotation, 0, 0, 1.0)
        glScalef(self.scale[0], self.scale[1], 1)
    def disable(self):
        glPopMatrix()
    def set_translation(self, newx, newy):
        self.translation = (float(newx), float(newy))
    def set_rotation(self, new):
        self.rotation = float(new)
    def set_scale(self, newx, newy):
        self.scale = (float(newx), float(newy))


class Color(Attr):
    def __init__(self, vec4):
        self.vec4 = vec4
    def enable(self):
        glColor4f(*self.vec4)


class LineStyle(Attr):
    def __init__(self, style):
        self.style = style
    def enable(self):
        glEnable(GL_LINE_STIPPLE)
        glLineStipple(1, self.style)
    def disable(self):
        glDisable(GL_LINE_STIPPLE)


class LineWidth(Attr):
    def __init__(self, stroke):
        self.stroke = stroke
    def enable(self):
        glLineWidth(self.stroke)


class Point(Geom):
    def __init__(self):
        Geom.__init__(self)
    def render1(self):
        glBegin(GL_POINTS) # draw point
        glVertex3f(0.0, 0.0, 0.0)
        glEnd()


class FilledPolygon(Geom):
    def __init__(self, v):
        Geom.__init__(self)
        self.v = v
    def render1(self):
        if   len(self.v) == 4 : glBegin(GL_QUADS)
        elif len(self.v)  > 4 : glBegin(GL_POLYGON)
        else: glBegin(GL_TRIANGLES)
        for p in self.v:
            glVertex3f(p[0], p[1],0)  # draw each vertex
        glEnd()


def make_circle(radius=10, res=30, filled=True):
    points = []
    for i in range(res):
        ang = 2*math.pi*i / res
        points.append((math.cos(ang)*radius, math.sin(ang)*radius))
    if filled:
        return FilledPolygon(points)
    else:
        return PolyLine(points, True)


def make_polygon(v, filled=True):
    if filled: return FilledPolygon(v)
    else: return PolyLine(v, True)


def make_polyline(v):
    return PolyLine(v, False)

def make_capsule(length, width):
    l, r, t, b = 0, length, width/2, -width/2
    box = make_polygon([(l,b), (l,t), (r,t), (r,b)])
    circ0 = make_circle(width/2)
    circ1 = make_circle(width/2)
    circ1.add_attr(Transform(translation=(length, 0)))
    geom = Compound([box, circ0, circ1])
    return geom

class Compound(Geom):
    def __init__(self, gs):
        Geom.__init__(self)
        self.gs = gs
        for g in self.gs:
            g.attrs = [a for a in g.attrs if not isinstance(a, Color)]
    def render1(self):
        for g in self.gs:
            g.render()


class PolyLine(Geom):
    def __init__(self, v, close):
        Geom.__init__(self)
        self.v = v
        self.close = close
        self.linewidth = LineWidth(1)
        self.add_attr(self.linewidth)
    def render1(self):
        glBegin(GL_LINE_LOOP if self.close else GL_LINE_STRIP)
        for p in self.v:
            glVertex3f(p[0], p[1],0)  # draw each vertex
        glEnd()
    def set_linewidth(self, x):
        self.linewidth.stroke = x


class Line(Geom):
    def __init__(self, start=(0.0, 0.0), end=(0.0, 0.0)):
        Geom.__init__(self)
        self.start = start
        self.end = end
        self.linewidth = LineWidth(1)
        self.add_attr(self.linewidth)

    def render1(self):
        glBegin(GL_LINES)
        glVertex2f(*self.start)
        glVertex2f(*self.end)
        glEnd()

class Image(Geom):
    def __init__(self, fname, width, height):
        Geom.__init__(self)
        self.width = width
        self.height = height
        img = pyglet.image.load(fname)
        self.img = img
        self.flip = False
    def render1(self):
        self.img.blit(-self.width/2, -self.height/2, width=self.width, height=self.height)

# ================================================================

class SimpleImageViewer(object):
    def __init__(self, display=None):
        self.window = None
        self.isopen = False
        self.display = display
    def imshow(self, arr):
        if self.window is None:
            height, width, channels = arr.shape
            self.window = pyglet.window.Window(width=width, height=height, display=self.display)
            self.width = width
            self.height = height
            self.isopen = True
        assert arr.shape == (self.height, self.width, 3), "You passed in an image with the wrong number shape"
        image = pyglet.image.ImageData(self.width, self.height, 'RGB', arr.tobytes(), pitch=self.width * -3)
        self.window.clear()
        self.window.switch_to()
        self.window.dispatch_events()
        image.blit(0,0)
        self.window.flip()
    def close(self):
        if self.isopen:
            self.window.close()
            self.isopen = False
    def __del__(self):
        self.close()

# ================================================================
#                    MY CODE START FROM HERE
# ================================================================

class Geom2d(object):
    def __init__(self, env, kp=np.array([[-1, 0], [1, 0]]), filled=True, color=(0.0, 0.0, 0.0, 1.0), parent=None):
        self.env = env
        self.kp = kp
        if len(kp) > 1:
            if np.amax(cdist(kp, kp)) < self.env.config.metadata['eps']:
                raise ValueError('Object is smaller than eps in simulator_config')
        else:
            if env.config.metadata['eps'] < 5:
                raise ValueError('Object is smaller than eps in simulator_config')
            

        self.parent = parent
        self.trans = []
        self.color = color
        self.filled = filled

    def _render(self):
        viewer = self.env.viewer

        c = np.mean(self.kp, axis=0) * self.env.scale
        self.sz = np.amax(cdist(self.kp, self.kp))
        if len(self.kp) == 1:
            # create a circle
            self.geom = make_circle(5 * self.env.scale, filled=self.filled)
            self.geom.add_attr(Transform(translation=kp))
            self.pts = np.array(self.geom.v) / self.env.scale
            self.sz = 2
        elif len(self.kp) == 2:
            radius = norm(self.kp[1] - self.kp[0]) / 2
            n_pts = radius * np.pi * 2 / self.env.config.metadata['eps']
            deg = np.linspace(0, np.pi * 2, n_pts)
            self.kp = np.array([np.cos(deg) * radius, np.sin(deg) * radius]).T
            self.geom = make_polygon(v=self.kp * self.env.scale, filled=self.filled)
            # TODO: interpolation
            self.pts = self.kp
            self.sz = radius * 2
        else:
            self.pts = self._interp(self.kp)
            self.geom = make_polygon(v=self.pts * self.env.scale, filled=self.filled)
            self.sz = np.amax(cdist(self.kp, self.kp))

        if len(self.color) == 3:
            self.geom.set_color_rgb(self.color)
        if len(self.color) == 4:
            self.geom.set_color_rgba(self.color)
        #self.trans.append(Transform(translation=(c[0], c[1])))


        # if the geom2d has parent, add on parents transformation
        if self.parent:
            for tran in self.parent.trans:
                self.trans.append(tran)
        for tran in self.trans:
            self.geom.add_attr(tran)

        return self.geom

    def _interp(self, pts):
        '''
        interpolate the polygon given vertices
        :param pts: a list of points
        :param n_pts: total number of points
        :return: a list of points with the length of n_pts
        '''
        out = []
        for i in range(-1, len(pts)-1):
            l_pts = np.ceil(np.linalg.norm(pts[i+1] - pts[i]) / self.env.config.metadata['eps'])
            x = np.linspace(pts[i, 0], pts[i + 1, 0],l_pts)
            y = np.linspace(pts[i, 1], pts[i + 1, 1], l_pts)
            seg = np.vstack((x, y)).T
            out.append(seg)
        return np.concatenate(out)

if __name__ == '__main__':
    kp = np.array([[-100, 100], [-100, -100], [100, -100], [100, 100]])
    n_pts = 180
    geom = Geom2d(None, kp=kp)