rectangle to draw a line

Hi, I'm using rectangle to draw a circle then a line in a for loop. However, when I draw the second line, after drawing the circle, the line width is slimmer than the previous drawn line and even the next drawn lines.

I'm confuzed. I saved the handle and looked at the first created line and compared it to the second line. However, they are identical. Any advice?

Thank you

 for m=1:10

   rectangle('parent',handles.Axes9,'Position',[x,y,30,30],'Curvature',...

             [1,1],'FaceColor',color);

   rectangle('parent',handles.Axes9,'Position',... 

              x+14,y+30,1,h],'FaceColor','black');
   text(x+8,y+15, {m},'fontsize',14,'color','black',...

             'fontweight','bold','parent',handles.Axes9);            
 end

Answer 1

[Image Analyst]

You probably need to use "hold on" in between those calls. But why not use line() or plot() to create a line? Why use rectangle to create a line?

[Vincent I]

The reason why is because I already use a plot and lines. Its easier for me to use delete(findobj(handles.Axes9,'Type','Text')) and delete(findobj(handles.Axes9,'Type','Rectangle')) than to keep a track of all of them.

Hold on and off did not work...

[Image Analyst]

If you used hold on then you would not have the same handle number for both lines. Because you said you do have the same number I think that the second line blew away the first one and reused the same handle number. Anyway, we can't run your code to test it.

[Vincent I]

when I said "they are identical" i didnt mean the handle number is the same. What I meant is that the handle is identical except the handle number. If

Below is a smiplified version of my code that shows the issue that I'm having:

 handles.Axes9=axes;
 set(handles.Axes9,'xlim',[0 800],'ylim',[0 300])
 color='green';

 for a=1:6

        switch a
            case 1
                x = 20; y = 10; h = 125;
            case 2
                x = 60; y = 10; h = 120;
            case 3
                x = 170; y = 10; h = 135;
            case 4
                x = 325; y = 10; h = 120;
            case 5
                x = 540; y = 10; h = 130;
            case 6
                x = 570; y = 10; h = 130;
        end

        rectangle('parent',handles.Axes9,'Position', [x,y,30,30],'Curvature',[1,1],'FaceColor',color);
        rectangle('parent',handles.Axes9,'Position',[x+14,y+30,1,h],'FaceColor','black');

        text(x+8,y+15,{a},'fontsize',14,'color','black','fontweight','bold','parent',handles.Axes9); 

    end

thank you

[Jan]

Do you mean: "that the line is identical except for the handle number"?

[Vincent I]

:-) yes. the rectangle "line" is identical except the handle number

Answer 2

[Jan]

This has been a useful example.

The code is correct and the display of the graphics is correct also. You see the effect, that rectangle draws to rounded pixel positions. And sometimes they are nearer to each other, such that the line looks smaller. When you resize the figure, you will see, that other lines are concerned.

[Vincent I]

so, i'll take it there's no way around this?

it is strange because in the code provided the first two lines are slimer than the rest. In my code the second line is the only one thats slim(see below).

[Vincent I]

ok so I think I might have found a way to get away from drawing the rectangle line and then delete it easily.

delete(findobj(findobj(0,'tag','Axes9'),'type','line'))

or

delete(findobj(findobj(0,'tag','Axes9'),'type','line'),'-or','type','rectangle'))

I think one of the reasons why I liked using rectangle is because Axes9 were the only axes that I was using rectangle. It was easy just to look at the main figure for rectangles and detele them. However since I've just figure it out how to delete all the lines from the Axes9.

yes I know I could just use delete(handles.Axes9...). However I'm trying to delete the lines/rectangle from a different *.m file

Thank you for your help

[Image Analyst]

I'm not sure if you still have a question or not.

[Malcolm Lidierth]

Does any of this help?:

http://undocumentedmatlab.com/blog/plot-linesmoothing-property/

[Vincent I]

fixed my issue by doing the following:

 rectangle('parent',findobj(0,'Tag','Axes9'),'Position', [x,y,30,30],'Curvature',[1,1],'FaceColor',color);

 line([x+15 x+15],[y+30 y+h],'LineWidth',2,'Color','Black','parent',findobj(0,'Tag','Axes9'))

and deleting everything with:

 delete(findobj(findobj(0,'tag','Axes9'),'Type','Text','-or','type','rectangle','-or','type','line'))

Thank you for all your help