How to create a simple single color visualization in simulink ?

Hi,I'm trying to visualize a single color in a simulink simulation. I would like to send a vector of 3 values [R,G,B] and simply have an that color displayed and updated live on some sort of screen/plot.

I have tried inserting an "matlab function" block and using this function:

function drawColor(RGB)
rectangle('FaceColor',RGB)

This works and displayes the color just like I want it to, but the display is updated very slowly.

Is there a proper way to do this ?

Answer 1

[prabhat kumar sharma]

Hi Michael,

The slow update you're experiencing might be due to the overhead of repeatedly creating graphics objects.

Here is another approach you can try.

• Create a MATLAB Function block in your Simulink model.
• Use the following code in the MATLAB Function block:

function drawColor(R, G, B)
    coder.extrinsic('set', 'rectangle', 'gcf', 'cla');
    persistent rect;
    
    if isempty(rect)
        % Create the rectangle once
        figure('Name', 'Color Display', 'NumberTitle', 'off');
        rect = rectangle('Position', [0, 0, 1, 1], 'FaceColor', [R, G, B]);
        axis off; % Turn off the axes for a cleaner look
    else
        % Update the rectangle's color
        set(rect, 'FaceColor', [R, G, B]);
        drawnow limitrate; % Optimize rendering speed
    end
end