I have a quesiton and I need your help. I have a raster graphic (a PNG file) that shows the upper part of a wind turbine. I would like to shift one of the rotor blades a little bit to the left (as indicated in the uploaded screenshot 'Change_Direction.PNG' ). Is there a sophisticated way how I can do this by using Inkscape? I used a very strange and unsophisticated method for doing it by using screenshots and MS paint (see uploaded screenshot 'Change_StrangeMethod.PNG'). I would appreciate every comment.
You'd have to convert the graphic to vector first. I would redraw the graphic by tracing over with circles and rectangles. It should be quick to do. Once it's vector you can adjust it much easier.
But as a raster graphic, it's not much good in Inkscape.
Agree with Martin, particularly with regard to manually tracing over the existing graphic.
There is a "Trace Bitmap" feature that you might be tempted by, but I'd recommend avoiding it for this task. This also turns the bitmap into a vector, but in doing so you'd end up with a single path with lots of nodes: making the adjustment you want would be possible, but requires some more advanced Inkscape skills.
Manually tracing the shapes, on the other hand, only requires some rudimentary skills - the sort covered in the first couple of tutorials under the Help menu. You'll be left with a set of separate objects that can then be individually manipulated. Rotating the blade a little is then very straightforward - just remember that you can reposition the centre of rotation by dragging it with the mouse, which will make it easier to rotate the blade round its end, rather than its centre.
I basically tried to automatically convert the bitmap into vector graphic but I was not able to change the vector graphic in the right way as it was too complex.
I also tried it with the Bezier tool but the shape did not look good.
@Martin: What do you mean by " tracing over with circles and rectangles". I tried it but it took quite much time and the result did not look good. So I do not really know how I can do this.
@Xav What do you mean by: " just remember that you can reposition the centre of rotation by dragging it with the mouse, which will make it easier to rotate the blade round its end, rather than its centre"
My biggest problem is to get a correct shape. The automatically created one looks good but unforunately is really strange to edit for me. I'd appreciate every further comment.
Manually tracing the shapes, on the other hand, only requires some rudimentary skills - the sort covered in the first couple of tutorials under the Help menu.
I suggest going through those tutorials first. Once you've done that you'll know how to draw rounded rectangles and circles, which are all the shapes you need for this. You'll also know how to rotate, in which case my comment about dragging the centre of rotation (the small cross when in rotate/skew mode) will make more sense.
The shape you're reproducing is not very complex to draw manually:
3 circles with a black fill.
1 circle with a white fill and black stroke.
Optionally group all these circles for the centre hub of the turbine.
1 rounded rectangle with a white fill and black stroke for the top blade. Duplicate it and rotate (after moving the centre of rotation) for the other two, then move the centre again to rotate the top blade to give the result you're looking for.
It shouldn't take long. If it is, then that suggests you need some more practice with the basics first, which is why I pointed you to the help menu.
Edit: Martin beat me to it, demonstrating exactly what I suggested above, just without the three extra black circles. With a combination of his video and my description, you should be able to make some progress.
Thanks Martin for the nice animation and thanks Xav for your comment,
Basically I am making some progress due to your great help. Unfortunately I can't hide the blades behin the inner circle. In the animation it just happens but I tried to play with the tools for placing objects in the fore or background but it did not help. I have attached a screenshot.
Thanks Owens for your answer. Basically it works but there is still something that I do not understand. When choosing the same width for the strokes of blade and the inner cycle, the stroke for the inner cycle looks way thinner. What is the reason for that? I uploaded two screenshots that shows this. Of course I know I could just increase the width but I would like to have the same width for all the objects.
@Vanessa_Fi The answer is not what Tyler has shown. The scaling factor is an issue if you resize objects, but once resized their stroke width number would change too.
The answer is that the red lines are the same width. It's just that the center object has a white fill which is set to paint over half the line, while the blades have no fill and so have nothing obscuring the inside half of the line.
I believe you may have been playing with the paint order buttons (the little grid of buttons with a circle and a box shown in different configurations.
Beginners' Questions Changing a raster graphic by using Inkscape
Inkscape.org
Hi guys,
I have a quesiton and I need your help. I have a raster graphic (a PNG file) that shows the upper part of a wind turbine. I would like to shift one of the rotor blades a little bit to the left (as indicated in the uploaded screenshot 'Change_Direction.PNG' ). Is there a sophisticated way how I can do this by using Inkscape? I used a very strange and unsophisticated method for doing it by using screenshots and MS paint (see uploaded screenshot 'Change_StrangeMethod.PNG'). I would appreciate every comment.
You'd have to convert the graphic to vector first. I would redraw the graphic by tracing over with circles and rectangles. It should be quick to do. Once it's vector you can adjust it much easier.
But as a raster graphic, it's not much good in Inkscape.
Agree with Martin, particularly with regard to manually tracing over the existing graphic.
There is a "Trace Bitmap" feature that you might be tempted by, but I'd recommend avoiding it for this task. This also turns the bitmap into a vector, but in doing so you'd end up with a single path with lots of nodes: making the adjustment you want would be possible, but requires some more advanced Inkscape skills.
Manually tracing the shapes, on the other hand, only requires some rudimentary skills - the sort covered in the first couple of tutorials under the Help menu. You'll be left with a set of separate objects that can then be individually manipulated. Rotating the blade a little is then very straightforward - just remember that you can reposition the centre of rotation by dragging it with the mouse, which will make it easier to rotate the blade round its end, rather than its centre.
Thanks Martin Owens and Xav for your answers,
I basically tried to automatically convert the bitmap into vector graphic but I was not able to change the vector graphic in the right way as it was too complex.
I also tried it with the Bezier tool but the shape did not look good.
@Martin: What do you mean by " tracing over with circles and rectangles". I tried it but it took quite much time and the result did not look good. So I do not really know how I can do this.
@Xav What do you mean by: " just remember that you can reposition the centre of rotation by dragging it with the mouse, which will make it easier to rotate the blade round its end, rather than its centre"
My biggest problem is to get a correct shape. The automatically created one looks good but unforunately is really strange to edit for me. I'd appreciate every further comment.
See this demonstration animation
As I said previously:
I suggest going through those tutorials first. Once you've done that you'll know how to draw rounded rectangles and circles, which are all the shapes you need for this. You'll also know how to rotate, in which case my comment about dragging the centre of rotation (the small cross when in rotate/skew mode) will make more sense.
The shape you're reproducing is not very complex to draw manually:
It shouldn't take long. If it is, then that suggests you need some more practice with the basics first, which is why I pointed you to the help menu.
Edit: Martin beat me to it, demonstrating exactly what I suggested above, just without the three extra black circles. With a combination of his video and my description, you should be able to make some progress.
Thanks Martin for the nice animation and thanks Xav for your comment,
Basically I am making some progress due to your great help. Unfortunately I can't hide the blades behin the inner circle. In the animation it just happens but I tried to play with the tools for placing objects in the fore or background but it did not help. I have attached a screenshot.
@Vanessa_Fi You will need to see the FILL of the objects. In my animation I set them to white so the objects would be obscured behind each other.
Thanks Owens for your answer. Basically it works but there is still something that I do not understand. When choosing the same width for the strokes of blade and the inner cycle, the stroke for the inner cycle looks way thinner. What is the reason for that? I uploaded two screenshots that shows this. Of course I know I could just increase the width but I would like to have the same width for all the objects.
One or another of the objects may have been scaled after creation.
@Vanessa_Fi The answer is not what Tyler has shown. The scaling factor is an issue if you resize objects, but once resized their stroke width number would change too.
The answer is that the red lines are the same width. It's just that the center object has a white fill which is set to paint over half the line, while the blades have no fill and so have nothing obscuring the inside half of the line.
I believe you may have been playing with the paint order buttons (the little grid of buttons with a circle and a box shown in different configurations.
Thanks a lot Martin for your great help 😀