Python OpenGL.GL.glEnable() Examples

def draw_box(self, x0, y0, x1, y1):
        '''Draws a selection box in the 3-D window.
        Coordinates are with respect to the lower left corner of the window.
        '''
        import OpenGL.GL as gl
        gl.glMatrixMode(gl.GL_PROJECTION)
        gl.glLoadIdentity()
        gl.glOrtho(0.0, self.size[0],
                   0.0, self.size[1],
                   -0.01, 10.0)

        gl.glLineStipple(1, 0xF00F)
        gl.glEnable(gl.GL_LINE_STIPPLE)
        gl.glLineWidth(1.0)
        gl.glColor3f(1.0, 1.0, 1.0)
        gl.glBegin(gl.GL_LINE_LOOP)
        gl.glVertex3f(x0, y0, 0.0)
        gl.glVertex3f(x1, y0, 0.0)
        gl.glVertex3f(x1, y1, 0.0)
        gl.glVertex3f(x0, y1, 0.0)
        gl.glEnd()
        gl.glDisable(gl.GL_LINE_STIPPLE)
        gl.glFlush()

        self.resize(*self.size) 

def drawToolReticle(self):
        pos, direction = self.editor.blockFaceUnderCursor
        x, y, z = map(lambda p, d: p + d, pos, direction)

        color = (1.0, 1.0, 1.0, 0.5)
        if isinstance(self.editor.level, pymclevel.MCInfdevOldLevel) and self.spawnProtection:
            if not positionValid(self.editor.level, (x, y, z)):
                color = (1.0, 0.0, 0.0, 0.5)

        GL.glColor(*color)
        GL.glEnable(GL.GL_BLEND)
        self.drawCage(x, y, z)
        self.drawCharacterHead(x + 0.5, y + 0.5, z + 0.5)
        GL.glDisable(GL.GL_BLEND)

        GL.glEnable(GL.GL_DEPTH_TEST)
        self.drawCage(x, y, z)
        self.drawCharacterHead(x + 0.5, y + 0.5, z + 0.5)
        color2 = map(lambda a: a * 0.4, color)
        drawTerrainCuttingWire(BoundingBox((x, y, z), (1, 1, 1)), color2, color)
        GL.glDisable(GL.GL_DEPTH_TEST) 

def drawFaceVertices(self, buf):
        if 0 == len(buf):
            return
        stride = elementByteLength

        GL.glVertexPointer(3, GL.GL_FLOAT, stride, (buf.ravel()))
        GL.glTexCoordPointer(2, GL.GL_FLOAT, stride, (buf.ravel()[3:]))
        GL.glColorPointer(4, GL.GL_UNSIGNED_BYTE, stride, (buf.view(dtype=numpy.uint8).ravel()[20:]))

        GL.glDepthMask(False)

        GL.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_LINE)

        GL.glLineWidth(2.0)
        GL.glDrawArrays(GL.GL_QUADS, 0, len(buf) * 4)

        GL.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_FILL)

        GL.glPolygonOffset(DepthOffset.TerrainWire, DepthOffset.TerrainWire)
        with gl.glEnable(GL.GL_POLYGON_OFFSET_FILL, GL.GL_DEPTH_TEST):
            GL.glDrawArrays(GL.GL_QUADS, 0, len(buf) * 4)
        GL.glDepthMask(True) 

def initializeGL(self):
        """Initialize OpenGL, VBOs, upload data on the GPU, etc."""

        # First check for supported GL version
        gl_version = float(gl.glGetString(gl.GL_VERSION)[:3])
        if gl_version < 3.3:
            return

        # background color
        gl.glClearColor(0, 0, 0, 0)
        gl.glEnable(gl.GL_BLEND)
        gl.glBlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)

        # self.mcp_data       = mcpUBO()
        self.globaldata     = ndUBO()
        self.mcp_col_shader = BlueSkyProgram('mcp.vert', 'color.frag')
        self.mcp_tex_shader = BlueSkyProgram('mcp.vert', 'texture.frag')
        self.mcp_txt_shader = BlueSkyProgram('mcp_text.vert', 'mcp_text.frag')

        self.color_shader   = BlueSkyProgram('normal.vert', 'color.frag')
        self.text_shader    = BlueSkyProgram('text.vert', 'text.frag')
        self.text_shader.bind_uniform_buffer('global_data', self.globaldata)

        self.create_objects()
        self.update_lcd() 

def drawTerrainCuttingWire(box,
                           c0=(0.75, 0.75, 0.75, 0.4),
                           c1=(1.0, 1.0, 1.0, 1.0)):
    # glDepthMask(False)
    GL.glEnable(GL.GL_DEPTH_TEST)

    GL.glDepthFunc(GL.GL_LEQUAL)
    GL.glColor(*c1)
    GL.glLineWidth(2.0)
    drawCube(box, cubeType=GL.GL_LINE_STRIP)

    GL.glDepthFunc(GL.GL_GREATER)
    GL.glColor(*c0)
    GL.glLineWidth(1.0)
    drawCube(box, cubeType=GL.GL_LINE_STRIP)

    GL.glDepthFunc(GL.GL_LEQUAL)
    GL.glDisable(GL.GL_DEPTH_TEST)
    # glDepthMask(True) 

def __init__(self, obj_info, color=None, swapyz=False):
        """Loads a Wavefront OBJ file. """
        self.vertices = obj_info.vertices
        self.normals = obj_info.normals
        self.texcoords = obj_info.texcoords
        self.faces = obj_info.faces
        self.color = color

        self.gl_list = GL.glGenLists(1)
        GL.glNewList(self.gl_list, GL.GL_COMPILE)
        # GL.glEnable(GL.GL_TEXTURE_2D)
        GL.glFrontFace(GL.GL_CCW)
        # GL.glDisable(GL.GL_LIGHT0)
        # GL.glDisable(GL.GL_LIGHTING)
        for face in self.faces:
            vertices, normals, _, _ = face
            GL.glColor3f(self.color[0], self.color[1], self.color[2])
            GL.glBegin(GL.GL_POLYGON)
            for i in range(len(vertices)):
                # if normals[i] > 0:
                #     GL.glNormal3fv(self.normals[normals[i] - 1])
                GL.glVertex3fv(self.vertices[vertices[i] - 1])
            GL.glEnd()
        GL.glDisable(GL.GL_TEXTURE_2D)
        GL.glEndList() 

def _drawCeiling():
        lines = []
        minz = minx = -256
        maxz = maxx = 256
        for x in range(minx, maxx + 1, 16):
            lines.append((x, 0, minz))
            lines.append((x, 0, maxz))
        for z in range(minz, maxz + 1, 16):
            lines.append((minx, 0, z))
            lines.append((maxx, 0, z))

        GL.glColor(0.3, 0.7, 0.9)
        GL.glVertexPointer(3, GL.GL_FLOAT, 0, numpy.array(lines, dtype='float32'))

        GL.glEnable(GL.GL_DEPTH_TEST)
        GL.glDepthMask(False)
        GL.glDrawArrays(GL.GL_LINES, 0, len(lines))
        GL.glDisable(GL.GL_DEPTH_TEST)
        GL.glDepthMask(True) 

def __init__(self, size, cam):

        app.Canvas.__init__(self, show=False, size=size)
        self.shape = (size[1], size[0])
        self.yz_flip = np.eye(4, dtype=np.float32)
        self.yz_flip[1, 1], self.yz_flip[2, 2] = -1, -1

        self.set_cam(cam)

        # Set up shader programs
        self.program_col = gloo.Program(_vertex_code_colored, _fragment_code_colored)
        self.program_tex = gloo.Program(_vertex_code_textured, _fragment_code_textured)

        # Texture where we render the color/depth and its FBO
        self.col_tex = gloo.Texture2D(shape=self.shape + (3,))
        self.fbo = gloo.FrameBuffer(self.col_tex, gloo.RenderBuffer(self.shape))
        self.fbo.activate()
        gloo.set_state(depth_test=True, blend=False, cull_face=True)
        gl.glEnable(gl.GL_LINE_SMOOTH)
        gloo.set_clear_color((0.0, 0.0, 0.0))
        gloo.set_viewport(0, 0, *self.size) 

def initgl(self):
        '''App-specific initialization for after GLUT has been initialized.'''
        import OpenGL.GL as gl
        self.gllist_id = gl.glGenLists(9)
        gl.glEnableClientState(gl.GL_VERTEX_ARRAY)
        gl.glEnableClientState(gl.GL_COLOR_ARRAY)
        gl.glDisable(gl.GL_LIGHTING)
        gl.glDisable(gl.GL_TEXTURE_2D)
        gl.glDisable(gl.GL_FOG)
        gl.glDisable(gl.GL_COLOR_MATERIAL)
        gl.glEnable(gl.GL_DEPTH_TEST)
        gl.glShadeModel(gl.GL_FLAT)
        self.set_data(self.data, classes=self.classes, features=self.features)

        try:
            import OpenGL.GLUT as glut
            glut.glutInit()
            self._have_glut = True
        except:
            pass 

def initgl(self):
        """Initialize OpenGL for use in the window."""
        import OpenGL.GL as gl
        import OpenGL.GLU as glu
        self.load_textures()
        gl.glEnable(gl.GL_TEXTURE_2D)
        gl.glClearColor(*self.clear_color)
        gl.glClearDepth(1.0)
        gl.glDepthFunc(gl.GL_LESS)
        gl.glEnable(gl.GL_DEPTH_TEST)
        gl.glShadeModel(gl.GL_SMOOTH)

        gl.glMatrixMode(gl.GL_PROJECTION)
        # Reset The projection matrix
        gl.glLoadIdentity()
        # Calculate aspect ratio of the window
        (width, height) = self.canvas.GetClientSize()
        glu.gluPerspective(45.0, float(width) / float(height), 0.1, 100.0)

        gl.glMatrixMode(gl.GL_MODELVIEW)
        gl.glLightfv(gl.GL_LIGHT0, gl.GL_AMBIENT, (0.5, 0.5, 0.5, 1.0))
        gl.glLightfv(gl.GL_LIGHT0, gl.GL_DIFFUSE, (1.0, 1.0, 1.0, 1.0))
        gl.glLightfv(gl.GL_LIGHT0, gl.GL_POSITION, (0.0, 0.0, 2.0, 1.0))
        gl.glEnable(gl.GL_LIGHT0) 

def drawFaceVertices(self, buf):
        if not len(buf):
            return
        stride = elementByteLength

        GL.glVertexPointer(3, GL.GL_FLOAT, stride, (buf.ravel()))
        GL.glTexCoordPointer(2, GL.GL_FLOAT, stride, (buf.ravel()[3:]))
        GL.glColorPointer(4, GL.GL_UNSIGNED_BYTE, stride, (buf.view(dtype=numpy.uint8).ravel()[20:]))

        GL.glDepthMask(False)

        GL.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_LINE)

        GL.glLineWidth(2.0)
        GL.glDrawArrays(GL.GL_QUADS, 0, len(buf) * 4)

        GL.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_FILL)

        GL.glPolygonOffset(DepthOffset.TerrainWire, DepthOffset.TerrainWire)
        with gl.glEnable(GL.GL_POLYGON_OFFSET_FILL, GL.GL_DEPTH_TEST):
            GL.glDrawArrays(GL.GL_QUADS, 0, len(buf) * 4)
        GL.glDepthMask(True) 

def drawFaceVertices(self, buf):
        if not len(buf):
            return
        stride = elementByteLength
  
        GL.glVertexPointer(3, GL.GL_FLOAT, stride, (buf.ravel()))
        GL.glTexCoordPointer(2, GL.GL_FLOAT, stride, (buf.ravel()[3:]))
        GL.glColorPointer(4, GL.GL_UNSIGNED_BYTE, stride, (buf.view(dtype=numpy.uint8).ravel()[20:]))
  
        GL.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_LINE)
  
        GL.glLineWidth(1)
        with gl.glEnable(GL.GL_DEPTH_TEST):
            GL.glDrawArrays(GL.GL_QUADS, 0, len(buf) * 4)
        GL.glLineWidth(2.0)
        with gl.glEnable(GL.GL_DEPTH_TEST):
            GL.glDrawArrays(GL.GL_QUADS, 0, len(buf) * 4)
        GL.glLineWidth(1.0)
  
        GL.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_FILL) 

def viewer_init(self, w, h):
    pangolin.CreateWindowAndBind('Map Viewer', w, h)
    gl.glEnable(gl.GL_DEPTH_TEST)

    self.scam = pangolin.OpenGlRenderState(
      pangolin.ProjectionMatrix(w, h, 420, 420, w//2, h//2, 0.2, 10000),
      pangolin.ModelViewLookAt(0, -10, -8,
                               0, 0, 0,
                               0, -1, 0))
    self.handler = pangolin.Handler3D(self.scam)

    # Create Interactive View in window
    self.dcam = pangolin.CreateDisplay()
    self.dcam.SetBounds(0.0, 1.0, 0.0, 1.0, w/h)
    self.dcam.SetHandler(self.handler)
    # hack to avoid small Pangolin, no idea why it's *2
    self.dcam.Resize(pangolin.Viewport(0,0,w*2,h*2))
    self.dcam.Activate() 

def drawTerrainCuttingWire(box,
                           c0=(0.75, 0.75, 0.75, 0.4),
                           c1=(1.0, 1.0, 1.0, 1.0)):
    # glDepthMask(False)
    GL.glEnable(GL.GL_DEPTH_TEST)

    GL.glDepthFunc(GL.GL_LEQUAL)
    GL.glColor(*c1)
    GL.glLineWidth(2.0)
    drawCube(box, cubeType=GL.GL_LINE_STRIP)

    GL.glDepthFunc(GL.GL_GREATER)
    GL.glColor(*c0)
    GL.glLineWidth(1.0)
    drawCube(box, cubeType=GL.GL_LINE_STRIP)

    GL.glDepthFunc(GL.GL_LEQUAL)
    GL.glDisable(GL.GL_DEPTH_TEST)
    # glDepthMask(True) 

def drawToolReticle(self):
        if self.movingPlayer is None:
            return

        pos, direction = self.editor.blockFaceUnderCursor
        dim = self.editor.level.getPlayerDimension(self.movingPlayer)
        pos = (pos[0], pos[1] + 2, pos[2])

        x, y, z = pos

        # x,y,z=map(lambda p,d: p+d, pos, direction)
        GL.glEnable(GL.GL_BLEND)
        GL.glColor(1.0, 1.0, 1.0, 0.5)
        self.drawCharacterHead(x + 0.5, y + 0.75, z + 0.5, self.revPlayerPos[dim][self.movingPlayer], dim)
        GL.glDisable(GL.GL_BLEND)

        GL.glEnable(GL.GL_DEPTH_TEST)
        self.drawCharacterHead(x + 0.5, y + 0.75, z + 0.5, self.revPlayerPos[dim][self.movingPlayer], dim)
        drawTerrainCuttingWire(BoundingBox((x, y, z), (1, 1, 1)))
        drawTerrainCuttingWire(BoundingBox((x, y - 1, z), (1, 1, 1)))
        #drawTerrainCuttingWire( BoundingBox((x,y-2,z), (1,1,1)) )
        GL.glDisable(GL.GL_DEPTH_TEST) 

def __init__(self, size, cam):

        app.Canvas.__init__(self, show=False, size=size)
        self.shape = (size[1], size[0])
        self.yz_flip = np.eye(4, dtype=np.float32)
        self.yz_flip[1, 1], self.yz_flip[2, 2] = -1, -1

        self.set_cam(cam)

        # Set up shader programs
        self.program_col = gloo.Program(_vertex_code_colored, _fragment_code_colored)
        self.program_tex = gloo.Program(_vertex_code_textured, _fragment_code_textured)

        # Texture where we render the color/depth and its FBO
        self.col_tex = gloo.Texture2D(shape=self.shape + (3,))
        self.fbo = gloo.FrameBuffer(self.col_tex, gloo.RenderBuffer(self.shape))
        self.fbo.activate()
        gloo.set_state(depth_test=True, blend=False, cull_face=True)
        gl.glEnable(gl.GL_LINE_SMOOTH)
        gloo.set_clear_color((0.0, 0.0, 0.0))
        gloo.set_viewport(0, 0, *self.size) 

def __init__(self, size, cam):

        app.Canvas.__init__(self, show=False, size=size)
        self.shape = (size[1], size[0])
        self.yz_flip = np.eye(4, dtype=np.float32)
        self.yz_flip[1, 1], self.yz_flip[2, 2] = -1, -1

        self.set_cam(cam)

        # Set up shader programs
        self.program_col = gloo.Program(_vertex_code_colored, _fragment_code_colored)
        self.program_tex = gloo.Program(_vertex_code_textured, _fragment_code_textured)

        # Texture where we render the color/depth and its FBO
        self.col_tex = gloo.Texture2D(shape=self.shape + (3,))
        self.fbo = gloo.FrameBuffer(self.col_tex, gloo.RenderBuffer(self.shape))
        self.fbo.activate()
        gloo.set_state(depth_test=True, blend=False, cull_face=True)
        gl.glEnable(gl.GL_LINE_SMOOTH)
        gloo.set_clear_color((0.0, 0.0, 0.0))
        gloo.set_viewport(0, 0, *self.size) 

def initializeGL(self):
        """Initialize OpenGL, VBOs, upload data on the GPU, etc."""

        # First check for supported GL version
        gl_version = float(gl.glGetString(gl.GL_VERSION)[:3])
        if gl_version < 3.3:
            return

        # background color
        gl.glClearColor(0, 0, 0, 0)
        gl.glEnable(gl.GL_BLEND)
        gl.glBlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)

        self.globaldata = ndUBO()

        try:
            # Compile shaders and link color shader program
            self.color_shader = BlueSkyProgram('data/graphics/shaders/nd-normal.vert', 'data/graphics/shaders/nd-color.frag')
            self.color_shader.bind_uniform_buffer('global_data', self.globaldata)

            # Compile shaders and link text shader program
            self.text_shader = BlueSkyProgram('data/graphics/shaders/nd-text.vert', 'data/graphics/shaders/nd-text.frag')
            self.text_shader.bind_uniform_buffer('global_data', self.globaldata)

        except RuntimeError as e:
            qCritical('Error compiling shaders in radarwidget: ' + e.args[0])
            return

        # Set initial zoom
        self.globaldata.set_zoom(4.0)

        self.create_objects() 

def release(cls):
            GL.glEnable(GL.GL_DEPTH_TEST)
            # GL.glEnable(GL.GL_CULL_FACE)
            GL.glEnable(GL.GL_TEXTURE_2D)
            GL.glDisable(GL.GL_BLEND) 

def bind(cls):
            GL.glDisable(GL.GL_DEPTH_TEST)
            # GL.glDisable(GL.GL_CULL_FACE)
            GL.glDisable(GL.GL_TEXTURE_2D)
            GL.glEnable(GL.GL_BLEND) 

def bind(cls):
            GL.glEnable(GL.GL_BLEND) 

def __init__(self, size, cam):

        app.Canvas.__init__(self, show=False, size=size)
        self.shape = (size[1], size[0])
        self.yz_flip = np.eye(4, dtype=np.float32)
        self.yz_flip[1, 1], self.yz_flip[2, 2] = -1, -1

        self.set_cam(cam)

        # Set up shader programs
        self.program_col = gloo.Program(_vertex_code_colored, _fragment_code_colored)
        self.program_bbox = gloo.Program(_vertex_code_colored, _fragment_code_bbox)
        self.program_tex = gloo.Program(_vertex_code_textured, _fragment_code_textured)
        self.program_bg = gloo.Program(_vertex_code_background, _fragment_code_background)

        # Texture where we render the color/depth and its FBO
        self.col_tex = gloo.Texture2D(shape=self.shape + (3,))
        self.fbo = gloo.FrameBuffer(self.col_tex, gloo.RenderBuffer(self.shape))
        self.fbo.activate()
        gloo.set_state(depth_test=True, blend=False, cull_face=True)
        gl.glEnable(gl.GL_LINE_SMOOTH)
        gloo.set_clear_color((0.0, 0.0, 0.0))
        gloo.set_viewport(0, 0, *self.size)

        # Set up background render quad in NDC
        quad = [[-1, -1], [1, -1], [1, 1], [-1, 1]]
        tex = [[0, 1], [1, 1], [1, 0], [0, 0]]
        vertices_type = [('a_position', np.float32, 2), ('a_texcoord', np.float32, 2)]
        collated = np.asarray(list(zip(quad, tex)), vertices_type)
        self.bg_vbuffer = gloo.VertexBuffer(collated)
        self.bg_ibuffer = gloo.IndexBuffer([0, 1, 2, 0, 2, 3]) 

def drawConstructionCube(self, box, color, texture=None):
        if texture is None:
            texture = self.sixteenBlockTex
        # textured cube faces

        GL.glEnable(GL.GL_BLEND)
        GL.glEnable(GL.GL_DEPTH_TEST)
        GL.glDepthMask(False)

        # edges within terrain
        GL.glDepthFunc(GL.GL_GREATER)
        try:
            GL.glColor(color[0], color[1], color[2], max(color[3], 0.35))
        except IndexError:
            raise
        GL.glLineWidth(1.0)
        mceutils.drawCube(box, cubeType=GL.GL_LINE_STRIP)

        # edges on or outside terrain
        GL.glDepthFunc(GL.GL_LEQUAL)
        GL.glColor(color[0], color[1], color[2], max(color[3] * 2, 0.75))
        GL.glLineWidth(2.0)
        mceutils.drawCube(box, cubeType=GL.GL_LINE_STRIP)

        GL.glDepthFunc(GL.GL_LESS)
        GL.glColor(color[0], color[1], color[2], color[3])
        GL.glDepthFunc(GL.GL_LEQUAL)
        mceutils.drawCube(box, texture=texture, selectionBox=True)
        GL.glDepthMask(True)

        GL.glDisable(GL.GL_BLEND)
        GL.glDisable(GL.GL_DEPTH_TEST) 

def selectionPointsFromDragResize(self):
        point = self.dragResizePoint()
        # glColor(1.0, 1.0, 0.0, 1.0)
        #        glPointSize(9.0)
        #        glBegin(GL_POINTS)
        #        glVertex3f(*point)
        #        glEnd()
        #

        #        facebox = BoundingBox(box.origin, box.size)
        #        facebox.origin[dim] = self.dragResizePosition
        #        facebox.size[dim] = 0
        #        glEnable(GL_BLEND)
        #
        #        drawFace(facebox, dim * 2)
        #
        #        glDisable(GL_BLEND)
        #
        side = self.dragResizeFace & 1
        dragdim = self.dragResizeFace >> 1
        box = self.selectionBox()

        o, m = list(box.origin), list(box.maximum)
        (m, o)[side][dragdim] = int(numpy.floor(point[dragdim] + 0.5))
        m = map(lambda a: a - 1, m)
        return o, m 

def main():
    pangolin.CreateWindowAndBind('Main', 640, 480)
    gl.glEnable(gl.GL_DEPTH_TEST)

    # Define Projection and initial ModelView matrix
    scam = pangolin.OpenGlRenderState(
        pangolin.ProjectionMatrix(640, 480, 420, 420, 320, 240, 0.2, 100),
        pangolin.ModelViewLookAt(-2, 2, -2, 0, 0, 0, pangolin.AxisDirection.AxisY))
    handler = pangolin.Handler3D(scam)

    # Create Interactive View in window
    dcam = pangolin.CreateDisplay()
    dcam.SetBounds(0.0, 1.0, 0.0, 1.0, -640.0/480.0)
    dcam.SetHandler(handler)

    while not pangolin.ShouldQuit():
        gl.glClear(gl.GL_COLOR_BUFFER_BIT | gl.GL_DEPTH_BUFFER_BIT)
        gl.glClearColor(1.0, 1.0, 1.0, 1.0)
        dcam.Activate(scam)
        
        # Render OpenGL Cube
        pangolin.glDrawColouredCube()

        # Draw Point Cloud
        points = np.random.random((100000, 3)) * 10
        colors = np.zeros((len(points), 3))
        colors[:, 1] = 1 -points[:, 0] / 10.
        colors[:, 2] = 1 - points[:, 1] / 10.
        colors[:, 0] = 1 - points[:, 2] / 10.

        gl.glPointSize(2)
        gl.glColor3f(1.0, 0.0, 0.0)
        # access numpy array directly(without copying data), array should be contiguous.
        pangolin.DrawPoints(points, colors)    

        pangolin.FinishFrame() 

def main():
    pangolin.CreateWindowAndBind('Main', 640, 480)
    gl.glEnable(gl.GL_DEPTH_TEST)

    # Define Projection and initial ModelView matrix
    scam = pangolin.OpenGlRenderState(
        pangolin.ProjectionMatrix(640, 480, 420, 420, 320, 240, 0.2, 100),
        pangolin.ModelViewLookAt(-2, 2, -2, 0, 0, 0, pangolin.AxisY))

    tree = pangolin.Renderable()
    tree.Add(pangolin.Axis())

    # Create Interactive View in window
    handler = pangolin.SceneHandler(tree, scam)
    dcam = pangolin.CreateDisplay()
    dcam.SetBounds(0.0, 1.0, 0.0, 1.0, -640.0 /480.0)
    dcam.SetHandler(handler)

    def draw(view):
        view.Activate(scam)
        tree.Render()
    dcam.SetDrawFunction(draw)

    while not pangolin.ShouldQuit():
        gl.glClear(gl.GL_COLOR_BUFFER_BIT | gl.GL_DEPTH_BUFFER_BIT)

        # or
        # dcam.Activate(scam)
        # tree.Render()

        pangolin.FinishFrame() 

def initializeGL(self):
        GL.glClearColor(1.0, 0.0, 0.0, 1.0)
        GL.glEnable(GL.GL_BLEND)
        GL.glBlendFunc (GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA)
        GL.glClear(GL.GL_COLOR_BUFFER_BIT)

        print("OpenGL.GL: " + str(GL.glGetString(GL.GL_VERSION)))
        print("GL.GLSL: " + str(GL.glGetString(GL.GL_SHADING_LANGUAGE_VERSION)))
        print("OpenGL ATTRIBUTES:\n",", ".join(d for d in dir(GL) if d.startswith("GL_")))

        self.program = QOpenGLShaderProgram()
        self.program.addShaderFromSourceCode(QOpenGLShader.Vertex, """#version 120
        attribute vec2 position;
        attribute vec2 texcoord;
        varying vec2 mytexcoord;
        void main() {
            gl_Position = vec4(position, 0., 1.0);
            mytexcoord = texcoord;
        }""")

        self.program.addShaderFromSourceCode(QOpenGLShader.Fragment, """#version 120
        uniform sampler2D texture;
        varying vec2 mytexcoord;
        void main() {
            
            gl_FragColor = texture2D(texture,mytexcoord);
        }""")
        print(self.program.log())
        self.program.link()

        self.texture = fillTexture2d(np.outer(np.linspace(0, 1, 128), np.ones(128))) 

def drawToolReticle(self):
        GL.glPolygonOffset(DepthOffset.SelectionReticle, DepthOffset.SelectionReticle)
        pos, direction = self.editor.blockFaceUnderCursor

        # draw a selection-colored box for the cursor reticle
        selectionColor = map(lambda a: a * a * a * a, self.selectionColor)
        r, g, b = selectionColor
        alpha = 0.3

        try:
            bt = self.editor.level.blockAt(*pos)
            if bt:
                # #                textureCoords = materials[bt][0]
                alpha = 0.12
        except (EnvironmentError, pymclevel.ChunkNotPresent):
            pass

        # cube sides
        GL.glColor(r, g, b, alpha)
        GL.glDepthMask(False)
        GL.glEnable(GL.GL_BLEND)
        GL.glEnable(GL.GL_DEPTH_TEST)
        drawCube(BoundingBox(pos, (1, 1, 1)))
        GL.glDepthMask(True)
        GL.glDisable(GL.GL_DEPTH_TEST)

        drawTerrainCuttingWire(BoundingBox(pos, (1, 1, 1)),
                               (r, g, b, 0.4),
                               (1., 1., 1., 1.0)
                               )

        GL.glDisable(GL.GL_BLEND) 

def initializeGL(self):
        self.qglClearColor(self.trolltechPurple.darker())
        self.object = self.makeObject()
        GL.glShadeModel(GL.GL_FLAT)
        GL.glEnable(GL.GL_DEPTH_TEST)
        GL.glEnable(GL.GL_CULL_FACE) 

def drawTerrainPreview(self, origin):
        if self.previewRenderer is None:
            return
        self.previewRenderer.origin = map(lambda a, b: a - b, origin, self.level.bounds.origin)

        GL.glPolygonOffset(DepthOffset.ClonePreview, DepthOffset.ClonePreview)
        GL.glEnable(GL.GL_POLYGON_OFFSET_FILL)
        self.previewRenderer.draw()
        GL.glDisable(GL.GL_POLYGON_OFFSET_FILL)