plannerLineSpec.tree

Specifications for plotting forward search tree

Since R2023b

Syntax

spec = plannerLineSpec.tree

spec = plannerLineSpec.tree(Name=Value)

[spec,structData] = plannerLineSpec.tree(___)

Description

spec = plannerLineSpec.tree specifies default color, line, and marker properties for plotting the forward search tree.

spec = plannerLineSpec.tree(Name=Value) specifies new values for the color, line, and marker properties by using one or more name-value arguments.

[spec,structData] = plannerLineSpec.tree(___) returns the properties and their values as a structure using any combination of inputs from the previous syntaxes.

Examples

Visualize Bi-RRT Path Planner Output Using Predefined Plot Specifications

Load Occupancy Map

Load a probability occupancy grid into the MATLAB® workspace.

load("exampleMaps.mat","simpleMap")

Create an occupancy map from the input occupancy grid.

map = occupancyMap(simpleMap);

Define the lower and upper limits of the state space variables x, y, and theta from the occupancy map.

x = map.XWorldLimits;
y =  map.YWorldLimits;
theta = [-pi pi];

Specify the start state and the goal state for path planning.

start = [2 5 0];
goal = [22 22 0];

Display the occupancy map.

figure
show(map)
hold on

Plot Start and Goal States

Use the plannerLineSpec.start and plannerLineSpec.goal functions to plot the start and goal states, respectively.

plot(start(1),start(2),plannerLineSpec.start{:})
plot(goal(1),goal(2),plannerLineSpec.goal{:})

Configure Bi-RRT Path Planner and Find Path Between Two States

Create a state space SE(2) object using the specified state space variables.

stateSpace = stateSpaceSE2([x; y; theta]);

Check the validity of the states in the input state space by using a state validator.

stateValidator = validatorOccupancyMap(stateSpace,Map=map);

Configure the Bi-RRT path planner.

planner = plannerBiRRT(stateSpace,stateValidator);

Compute the path between the start point and the goal point using Bi-RRT path planner.

[path,info] = plan(planner,start,goal)

path = 
  navPath with properties:

      StateSpace: [1x1 stateSpaceSE2]
          States: [306x3 double]
       NumStates: 306
    MaxNumStates: Inf

info = struct with fields:
          IsPathFound: 1
             ExitFlag: 1
        NumIterations: 294
        StartTreeData: [569x3 double]
         GoalTreeData: [710x3 double]
    StartTreeNumNodes: 189
     GoalTreeNumNodes: 236

Plot Search Trees

Use the plannerLineSpec.tree function to plot the forward search tree.

startTree = plannerLineSpec.tree;
plot(info.StartTreeData(:,1),info.StartTreeData(:,2),startTree{:})

Use the plannerLineSpec.goalTree function to plot the search tree from the goal state to the start state. Set the line color for plotting the search tree from goal to start to cyan.

goalTree = plannerLineSpec.goalTree(color="cyan");
plot(info.GoalTreeData(:,1),info.GoalTreeData(:,2),goalTree{:})
legend

Plot Computed Path

Use the plannerLineSpec.path function to plot the derived path.

plot(path.States(:,1),path.States(:,2),plannerLineSpec.path{:})
legend(Position=[0.8 0.11 0.2 0.2])

Visualize RRT Path Planner Output Using Custom Plot Specifications

Load Occupancy Map

Load a probability occupancy grid into the MATLAB® workspace.

load("exampleMaps.mat","simpleMap")

Create an occupancy map from the input occupancy grid.

map = occupancyMap(simpleMap);

Define the lower and upper limits of the state space variables x, y, and theta from the occupancy map.

x = map.XWorldLimits;
y =  map.YWorldLimits;
theta = [-pi pi];

Display the occupancy map.

figure
show(map)
hold on

Specify the start state and the goal state for path planning.

start = [2 5 0];
goal = [22 22 0];

Plot Start and Goal States

Use the plannerLineSpec.start and plannerLineSpec.goal functions to plot the start and goal states, respectively.

plot(start(1),start(2),plannerLineSpec.start{:})

Set the color for plotting the goal state to red and plot the goal state.

goalState = plannerLineSpec.goal(MarkerEdgeColor="red",MarkerFaceColor="red");
plot(goal(1),goal(2),goalState{:})

Configure RRT Path Planner

Create a state space SE(2) object using the specified state space variables.

stateSpace = stateSpaceSE2([x; y; theta]);

Check the validity of the states in the input state space by using a state validator.

stateValidator = validatorOccupancyMap(stateSpace,Map=map);

Configure the RRT path planner.

planner = plannerRRT(stateSpace,stateValidator);

Find Path Between Two States

Compute the path between the start point and the goal point using the RRT path planner.

[path,info] = plan(planner,start,goal)

path = 
  navPath with properties:

      StateSpace: [1x1 stateSpaceSE2]
          States: [320x3 double]
       NumStates: 320
    MaxNumStates: Inf

info = struct with fields:
      IsPathFound: 1
         ExitFlag: 1
         NumNodes: 1192
    NumIterations: 1331
         TreeData: [3578x3 double]

Plot Search Trees

Use the plannerLineSpec.tree function to plot the forward search tree. Set the color for plotting the search tree to green.

In addition, set the legend label to "Forward search tree".

startTree = plannerLineSpec.tree(Color="green",DisplayName="Forward search tree");
plot(info.TreeData(:,1),info.TreeData(:,2),startTree{:})

Plot Computed Path

Use the plannerLineSpec.path function to plot the derived path.

plot(path.States(:,1),path.States(:,2),plannerLineSpec.path{:})
legend(Position=[0.6 0.11 0.2 0.2])

Input Arguments

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Example: plannerLineSpec.tree(Color="Red")

Color — Line color

"#FFAB66" (default) | RGB triplet | character vector | string scalar

Line color, specified as one of these values:

• RGB triplet — Specify the intensities of the red, green, and blue components of the color as a three-element vector in the order [R G B]. Each intensity must be in the range [0, 1]. For example, you can specify a shade of pink as [1 0.5 0.8].

• Character vector or string scalar — Specify the hexadecimal color code, color name, or short name of the color.

For more information on the types of color values and how to specify them, see Specify Plot Colors.

LineStyle — Line style

"-" (default) | "--" | ":" | "-." | "none"

Line style, specified as one of these values:

• "-" — For a solid line. This is the default.

• "--" — For a dashed line.

• ":" — For a dotted line.

• "-." — For a dash-dotted line.

• "none" — For no line.

LineWidth — Line width

1 (default) | positive numeric scalar

Line width, specified as a positive numeric scalar.

Marker — Marker symbol

"." (default) | "o" | "+" | "*" | "x" | ...

Marker symbol, specified as one of the values listed in this table.

Marker	Description	Resulting Marker
"o"	Circle
"+"	Plus sign
"*"	Asterisk
"."	Point
"x"	Cross
"_"	Horizontal line
"|"	Vertical line
"square"	Square
"diamond"	Diamond
"^"	Upward-pointing triangle
"v"	Downward-pointing triangle
">"	Right-pointing triangle
"<"	Left-pointing triangle
"pentagram"	Pentagram
"hexagram"	Hexagram
"none"	No markers	Not applicable

MarkerSize — Marker size

2 (default) | positive numeric scalar

Marker size, specified as a positive numeric scalar.

MarkerEdgeColor — Marker outline color

"#FFAB66" (default) | RGB triplet | character vector | string scalar

Marker outline color, specified as one of these values:

• RGB triplet — Specify the intensities of the red, green, and blue components of the color as a three-element vector in the order [R G B]. Each intensity must be in the range [0, 1]. For example, you can specify a shade of pink as [1 0.5 0.8].

• Character vector or string scalar — Specify the hexadecimal color code, color name, or short name of the color.

For more information on the types of color values and how to specify them, see Specify Plot Colors.

MarkerFaceColor — Marker fill color

"#FFAB66" (default) | RGB triplet | character vector | string scalar

Marker fill color, specified as one of these values:

• RGB triplet — Specify the intensities of the red, green, and blue components of the color as a three-element vector in the order [R G B]. Each intensity must be in the range [0, 1]. For example, you can specify a shade of pink as [1 0.5 0.8].

• Character vector or string scalar — Specify the hexadecimal color code, color name, or short name of the color.

For more information on the types of color values and how to specify them, see Specify Plot Colors.

DisplayName — Label to include in legend

"Tree" (default) | character vector | string scalar

Label to include in the legend, specified as a character vector or string scalar.

Output Arguments

spec — Color, line, and marker specifications

cell array

Color, line, and marker specifications for plotting the forward search tree, returned as a cell array of size 1-by-16.

Data Types: cell

structData — Specifications for the plot

structure

Specifications for the plot, returned as a structure with fields Color, LineStyle, LineWidth, Marker, MarkerSize, MarkerEdgecolor, MarkerFaceColor, and DisplayName. Each field contains the value specified to the corresponding name-value argument.

Data Types: struct

Version History

Introduced in R2023b