Rotating text using center in itext - rotation

I'm converting a document which is created with a online editor. I need to be able to rotate the text using it's central point and not (0,0).
Since Image rotates using the centre I assumed this would work but it doesn't. Anyone has a clue how to rotate text using the central point in itext?
float fw = bf.getWidthPoint(text, textSize);
float fh = bf.getAscentPoint(text, textSize) - bf.getDescentPoint(text, textSize);
PdfTemplate template = content.createTemplate(fw, fh);
Rectangle r = new Rectangle(0,0,fw, fw);
r.setBackgroundColor(BaseColor.YELLOW);
template.rectangle(r);
template.setFontAndSize(bf, 12);
template.beginText();
template.moveText(0, 0);
template.showText(text);
template.endText();
Image tmpImage = Image.getInstance(template);
tmpImage.setAbsolutePosition(Utilities.millimetersToPoints(x), Utilities.millimetersToPoints(pageHeight-(y+Utilities.pointsToMillimeters(fh))));
tmpImage.setRotationDegrees(0);
document.add(tmpImage);

Why are you using beginText(), moveText(), showText(), endText()? Those methods are to be used by developers who speak PDF syntax fluently. Other developers should avoid using those low-level methods, because they are bound to make errors.
For instance: you're using the setFontAndSize() method outside a text object. That method is forbidden in graphics state, you can only use it in text state. Although Adobe Reader will probably tolerate it, Acrobat will complain when doing a syntax check.
Developers who don't speak PDF syntax fluently are advised to use convenience methods as demonstrated in the TextMethods example. Take a look at text_methods.pdf. The text "Away again Center" is probably what you need.
However, there's even an easier way to achieve what you want. Just use the static showTextAligned() method that is provided in the ColumnTextclass. That way you don't even need to use beginText(), setFontAndSize(), endText():
ColumnText.showTextAligned(template,
Element.ALIGN_CENTER, new Phrase(text), x, y, rotation);
Using the showTextAligned() method in ColumnText also has the advantage that you can use a phrase that contains chunks with different fonts.

For those who use Paragraph in itext 7 :
paragraph.setFixedPosition(....)
paragraph.setRotationAngle(Math.toRadians(....));
paragraph.setProperty(Property.ROTATION_POINT_X, textCenterX);
paragraph.setProperty(Property.ROTATION_POINT_Y, textCenterY);

Related

Winapi How do I draw a rectangle to a specific Window handle?

I'm Using a Wrapper Library in GMS2 That was made back in GM6 Days (gamemaker) Someone was able to wrap majority of the win32API to use in GM6-8. There is only 1 odd instance in where the WinAPI system seems to mess up when drawing the controls to the Main Application Window.
The desired goal is to draw an image to an Child window and draw a grid defining it's splitting according to the user input EX: 16x16 and having the user select squares VIA Mouse Click + Dragging over the boxes.
Unfortunately I have little to no experience in win32API so i'm a bit lost as to where to start.
Looking over the documentation it looks like he left majority of the script names of the DLL to mimic the format of that when calling in C++ or C (just my assumptions).
From His Documentation he has things like "Drawing System" Which Contains things like "Move Item","Add Line","Add Graphic Buffer" etc... and then other Graphic Buffer functions. But then theres the "Draw" functions which has things like "Draw Fill Rect , DrawSelectObj" etc... he doesn't really provide examples so i'm unsure as to how to use these things together to get my desired results. What is the difference between a drawing system and a draw function? Do I have to use them in conjunction, along with the Graphics Buffer?
Can Someone point in the right direction of the necessary steps to get it done? An Example without code and just the function equivalent will suffice, I just need to know out of which functions to use and then later bind it to the Child Window.
An Example Code from his demo is something like this
GbGradient2 = API_GB_Create (105,105); //Graphics Buffer
DcGradient2 = API_GB_GetDC (GbGradient2);
API_Draw_Gradient (DcGradient2,0,0,105,105,0,c_yellow,c_lime);
BrGradient2 = API_Draw_CreatePatternBrush (API_GB_GetBitmap (GbGradient2));
API_Draw_Gradient (DcGradient2,0,0,105,105,0,c_red,65535);
BrGradient3 = API_Draw_CreatePatternBrush (API_GB_GetBitmap (GbGradient2));
hRectangle = API_DS_AddRectangle (2,5,5,105,105); // Adds a rectangle(Drawing System)
hEllipse = API_DS_AddEllipse (2,5,5,105,105);
hNoPen = API_Draw_CreatePen (PS_NULL,0,0);
API_DS_SetItemBrush (hRectangle,BrGradient2); // Sets the brush
API_DS_SetItemBrush (hEllipse,BrGradient3);
API_DS_SetItemPen (hRectangle,hNoPen); // Sets the pen
API_DS_SetItemPen (hEllipse,hNoPen);
API_Draw_Gradient (GbGradient2,0,0,16,16,0,c_yellow,c_lime);
Lookin at it a little more it looks like the draw functions are linked to GDI somehow.
since GMS2 is a cross platform tool , its windows-only functionality gas been removed.
you can make a nice GUI for that porpose by using GMS2 objects , as you have a little Xp
about Win32 API,this will be easier than that big stuffy coding
here are some tips ,
creating a window object with a rectangle sprite
creating ui objects at the create event of above object
adding some code to the global mouse event

Can I set an image, pixel by pixel, in Apps Script?

Preferably, I'd like to use an array, iterating over each pixel and setting the R G B values.
And I don't think that I can use HTML canvas in any way. I'm hoping to build it right on top of a Google Doc without additional libraries or references to external websites.
Everything I have found on the Image Class, type is about positioning or resizing, but not helpful for stating the image.
ImageItem .setImage() looks promising, but is not particularly descriptive.
You can implement your own encoding algorithm (or migrate someone else's) and transform your pixels array into an image blob compatible with the ImageItem.setImage() method.

How to generate texture mapping images?

I want to put/wrap images to 3D objects. To keep things simple and fast, instead of using(and learning) a 3D library I want to use mapping images. Mapping images are used in such a way:
So you generate the mapping images once for each object and use the same mapping for all images you want to wrap.
My question is how can I generate such mapping images (given the 3D model)? Since I don't know about the terminology my searches failed me. Sorry if I am using the wrong jargon.
Below you can see a description of the workflow.
I have the 3D model of the object and the input image, i want to generate mapping images that I can use to generate the textured image.
I don't even know where to start, any pointers are appreciated.
More info
My initial idea was to somehow wrap a identity mappings (see below) using an external program. I have generated horizontal and vertical gradient images in Photoshop just to see if mapping works using photoshop generated images. The result doesn't look good. I wasn't hopeful but it was worth a shot.
input
mappings (x and y), they just resize the image, they don't do anything fancy.
result
as you can see there are lots of artifacts. Custom mapping images I have generated by warping the gradients even looks worse.
Here is some more information on mappings: http://www.imagemagick.org/Usage/mapping/#distortion_maps
I am using OpenCV remap() function for mapping.
if i understand you right here, you want to do all of it in 2D ?
calling warpPerspective() for each of your cube surfaces will be much more successful, than using remap()
pseudocode outline:
// for each surface:
// get the desired src and dst polygon
// the src one is your texture-image, so that's:
vector<Point> p_src(4), p_dst(4);
p_src[0] = Point(0,0);
p_src[1] = Point(0,src.rows-1);
p_src[2] = Point(src.cols-1,0);
p_src[3] = Point(src.cols-1,src.rows-1);
// the dst poly is the one you want textured, a 3d->2d projection of the cube surface.
// sorry, you've got to do that on your own ;(
// let's say, you've come up with this for the cube - top:
p_dst[0] = Point(15,15);
p_dst[1] = Point(44,19);
p_dst[2] = Point(56,30);
p_dst[3] = Point(33,44);
// now you need the projection matrix to transform from one to another:
Mat proj = getPerspectiveTransform( p_src, p_dst );
// finally, you can warp your texture to the dst-polygon:
warpPerspective(src, dst, proj, dst.size());
if you can get hold of the 'Learning Opencv' book, it's described around p 170.
final word of warning, since youre complaining about artefacts, - yes, it'll all look pretty cheesy, 'real' 3d engines do a lot of work here, subpixel-uv mapping, filtering,
mipmapping, etc. if you want it to look nice, consider using the 'real' thing.
btw, there's nice opengl support built into opencv
To achieve what you are trying to do, you need to render the 3D-models UV to a texture. It will be easier to learn to render 3D than to do things this way. Especially since there are a lot of weaknesses in your aproach. difficult to to lighting and problems til the depth-buffer will be abundant.
Assuming all your objects shul ever only be viewed from one angle, you need to render each of them to 3 textures:
UV-map
Normal-map
Depth-map (to correct the depth-buffer)
You will still have to do shading in order to draw these to look like your object, and I don't even know how to do the depth-buffer-thing, I just know it can be done.
So in order to avoid learning 3D, your will have to learn all the difficult parts of 3D-rendering. Does not seem the easier route...

How to see image data using opencv in visual studio?

I wrote an OPENCV project in VS2010 and the results were not the ones as I expected so I ran the debugger to see where is the problem. When I wanted to see the data inside the image loaded I didn't know how to do it so if I want to see the data inside my images what should I do?
It is pretty simple in matlab for seeing different channel of an image i.e.
a=imread('test.jpg');
p1 = a(:,:,1)
p2 = b(:,:,2)
.
.
In opencv I wrote the same thing but I don't know how to see all the element at once just like Matlab.
a= imread("test.jpg")
split(a,planes);
vector<Mat> T1;
T1 = planes[0];
// How can I see the data inside T1 when debugging the code ?
I think this is what you are looking for - it's a great Visual Studio add-on
https://bitbucket.org/sergiu/opencv-visualizers
Just download the installer, make sure VS is closed, run it, re-open VS and voila! Now, when you point to an OpenCV data structure, all kinds of nice info is showed.
Limitations: I saw some problems with multichannel images (it only shows the first channel) and it also has trouble displaying large matrices. If you want to see raw data in a big matrix, you can use the old good VS trick with debug variables: Stop at a breakpoint, go to Watch tab, and write there
((float*)myMat.data) ,10
Where float is the matrix type, myMat is your matrix, and 10 is the number of values you want to print. It will display the first 10 values at the memory location of myMat.data. If you do not correctly choose the data type, you'll see garbage. In my example, myMat is of type cv::Mat.
And never forget the power of visualizers:
imshow("Image", myMat);
If your data fits into an image. You can use the contrib module's colormap to enhance your visualizers.
I can't actually believe that nobody suggested Image Watch yet. It's the most amazing add-in ever. It shows you a view with all your Mat variables (images (gray and color), matrices) while debugging, there's useful stuff like zooming or contrast-stretching and you can even apply more complex functions directly in the plugin in real-time. It makes debugging of any kind of image operations a breeze and it's immensely helpful if you do calculations and linear algebra stuff with your cv::Mat matrices.
I recommend to use a NativeViewer extension. It actually displays the content of an image in a preview window, not only the properly formatted info.
If you don't want to use a plug-in or extension to Visual Studio, you can access the elements one by one in the debugging watch tab by typing this:
T1.data[T1.step.buf[0]*i + T1.step.buf[1]*j];
where i is the row you want to look at and j is the column.
after downloading imagewatch use the command in watch window
(imagesLoc._Myfirst)[0]
index of image in the vector
You can use the immediate window and the extenshion method like this one
/// <summary>
/// Displays image
/// </summary>
public static void Display (this Mat m, Rect rect = default, string windowName = "")
{
if (string.IsNullOrEmpty(windowName))
{
windowName = m.ToString();
}
var img = rect == default ? m : m.Crop(rect);
double coef = Math.Min(1600d / img.Width, 800d / img.Height);
Cv2.ImShow(windowName, img.Resize(new Size(coef * img.Width, (coef * img.Height) > 1 ? coef * img.Height : 1)));
Cv2.WaitKey();
}
Then you stop at a breakpoint and call yourImage.Display() in the immediate window.
If you can use CLion you can utilize the OpenCV Image Viewer plugin, which displays matrices while debugging just on click.
https://plugins.jetbrains.com/plugin/14371-opencv-image-viewer
Disclaimer: I'm an author of this plugin

Windows phone append a border to an image

I'd like to append a border (20px white) to an image, save as a new jpeg image (orginal image with a border), I don't know how do I start. Can anyone give me a direction or code example?
Thanks
You have two ways to do it:
On your UI, wrap the image with a Border element with the correct settings and use new WriteableBitmap(borderElement, null) to create a new WriteableBitmap which you can then save using the SaveJpeg extension method.
Your other option is to use the WriteableBitmapEx class library to graphically add the graphical elements you want.
I've used both. The advantages for (1) is that there's less hassle in the sense of adding a dependeny on another DLL. The advantage in (2) is that you don't need to mess with your UI to create the image.

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