def render()

in gym-minigrid/gym_minigrid/minigrid.py [0:0]

• 34 lines of code
• 12 McCabe index (conditional complexity)

    def render(self, mode='human', close=False, highlight=True, tile_size=TILE_PIXELS):
        """
        Render the whole-grid human view
        """

        if close:
            if self.window:
                self.window.close()
            return

        if mode == 'human' and not self.window:
            import gym_minigrid.window
            self.window = gym_minigrid.window.Window('gym_minigrid')
            self.window.show(block=False)

        # Compute which cells are visible to the agent
        _, vis_mask = self.gen_obs_grid()

        # Compute the world coordinates of the bottom-left corner
        # of the agent's view area
        f_vec = self.dir_vec
        r_vec = self.right_vec
        top_left = self.agent_pos + f_vec * (self.agent_view_size-1) - r_vec * (self.agent_view_size // 2)

        # Mask of which cells to highlight
        highlight_mask = np.zeros(shape=(self.width, self.height), dtype=np.bool)

        # For each cell in the visibility mask
        for vis_j in range(0, self.agent_view_size):
            for vis_i in range(0, self.agent_view_size):
                # If this cell is not visible, don't highlight it
                if not vis_mask[vis_i, vis_j]:
                    continue

                # Compute the world coordinates of this cell
                abs_i, abs_j = top_left - (f_vec * vis_j) + (r_vec * vis_i)

                if abs_i < 0 or abs_i >= self.width:
                    continue
                if abs_j < 0 or abs_j >= self.height:
                    continue

                # Mark this cell to be highlighted
                highlight_mask[abs_i, abs_j] = True

        # Render the whole grid
        img = self.grid.render(
            tile_size,
            self.agent_pos,
            self.agent_dir,
            highlight_mask=highlight_mask if highlight else None
        )

        if mode == 'human':
            self.window.set_caption(self.mission)
            self.window.show_img(img)

        return img