I want to crop specific rect (x,y,width,height) of a PDF page. Is that possible with pdf.js?
Get the canvas reference of the page. Let us say your current scale is 133% so you need to multiply your coordinates by 1.33
var context = document.getElementById("page1").getContext('2d');
var imageData = context.getImageData(
160.89*(1.33),
193.97*(1.33),
517.29*(1.33),
148.87*(1.33))
Then you can put it to some other canvas or do something with it
context.putImageData(imageData,0,0);
Related
I am using iOS Charts (Daniel Gindi) to generate graphs in an iOS app and I want to be able to generate a PDF report with those graphs included in the body of the report. Can anyone explain how to go about doing this. Ideally I don't want to generate an image from the UIView that shows in the app because the size/resolution would not be suitable for the PDF document.
As I understand it there are a few options:
use the graphics context for the pdf document to draw the graph on - it's not clear whether this would be possible when using the Charts library
use a UIView somehow to generate the graph and generate a PDF image data from that, embed this image into the pdf report
It seems like option 1 is probably the preferred way to get best resolution/control - somewhat speculative - doing it this way means you should be able to specify the exact position and size and get the correct font sizes, line thicknesses, etc..
Using option 2 means you have to figure out the scaling between a UIView and the PDF page view and I am not sure how these would map to each other.
Can anyone provide any suggestions on the following:
Is it possible to use Charts to generate graphs in a PDF document, and if so how?
If not what other options are there, short of writing custom drawing code.
OK so here is what I have done
Option 1: Using a UIView.layer to render on the PDF CGContect
func drawLineGraph(x: CGFloat, y: CGFloat)->CGRect{
let width = (pageSize.width - 2*kBorderInset - 2*kMarginInset)/2.0 - 50.0
let renderingRect = CGRect(x: x, y: y + 50.0, width: width, height: 150.0)
// Create a view for the Graph
let graphController = LineChartController(rect: renderingRect, building: self.building)
if let currentContext = UIGraphicsGetCurrentContext() {
let frame = graphController.chartView.frame
currentContext.saveGState()
currentContext.translateBy(x:frame.origin.x, y:frame.origin.y);
graphController.chartView.layer.render(in: currentContext)
currentContext.restoreGState()
}
return renderingRect
}
The graphController is just an object that has essentially the same function as the usual parent ViewController that would contain the graph. Sets the graph parameters and data.
Once that has been done the function below is called to render on the PDF page context.
A bit of translation required to put the graphs in the correct position.
Option 2: Drawing on the PDF Page CGContect
And the solution is...ta da...
func drawBarGraph(x: CGFloat, y: CGFloat)->CGRect{
let width = (pageSize.width - 2*kBorderInset - 2*kMarginInset)/2.0 - 50.0
let renderingRect = CGRect(x: x + width + 50, y: y + 50.0, width: width, height: 150.0)
// Create a view for the Graph
let graphController = BarChartController(rect: renderingRect, building: self.building)
if let currentContext = UIGraphicsGetCurrentContext() {
let frame = graphController.chartView.frame
currentContext.saveGState()
currentContext.translateBy(x:frame.origin.x, y:frame.origin.y)
//graphController.chartView.layer.render(in: currentContext)
graphController.chartView.draw(frame)
currentContext.restoreGState()
}
return renderingRect
}
Since the current context is set to the PDF page's context just call the charts draw() function directly passing the frame rectangle.
What have I missed here, can it be this easy ?
You can find a copy of the generated PDF here as well as sample code.
I am trying to create a pdf from a webpage using phantomJS. I want the pdf to just be a single page long that is the same height as my webpage. If I don't set paperSize or viewportSize at all then it creates a page that is almost the right height, it is just a little short by about 100px. If I detect page height and use that to set viewportSize I have the exact same problem, it's short by about 100px. Is there a way to get phantomJS to just create a pdf based on the webpage's size? I want it to be exact because the page is a dark colour and it looks really bad to have a big white block at the end of the page (which is what is there if I add a constant to viewport height to make it fit everything in one page).
My code to find height(Note: the height is the same whether I use body or the classname below to find it):
var size = page.evaluate(function() {
var height = $('.export-athlete-detail-report').outerHeight(true);
return {width: 700, height:height};
});
page.paperSize = size;
page.render(reportFile);
I was created a new project using flash cc html5 canvas and created a movieclip with 200px width and 200px height. I can able to get the properties using this.mc.nominalBounds;. And I tried this.mc.getBounds ();
But it returns null. setBounds also not seems to work.
The setBounds method is for putting a custom bounds on something, or defining it when it can not be determined (like using the Graphics classes). Fortunately, all symbols from Flash CC come with nominalBounds, which is the combined, untransformed size of the symbol.
Using that, you can set the scaleX and scaleY properties to size up and down your content. If you want it to be a specific width, just use the nominalBounds to determine a new scale.
For example, if the clip is 200x200, and you want it to be 400x400, then:
var scale = newWidth / nominalBounds.width;
clip.scaleX = clip.scaleY = scale;
Hope that helps!
Is there any way to change the sc-waveform container background from #efefef without having to load the waveform.js library? I have enough libraries loading already and the conainer bg conflicts with our site background color
I am experiencing the same issue and have had this problem before ( Overlay visible areas of transparent black silhouette PNG with pattern using CSS3 or JS ).
Here is an example with your waveform: http://jsfiddle.net/eLmmA/3/
$(function() {
var canvas = document.createElement('canvas');
canvas.width = 1800; // must match
canvas.height = 280; // must match
var canvas_context = canvas.getContext("2d");
var img = new Image();
img.onload = function(){
var msk = new Image();
msk.onload = function(){
canvas_context.drawImage(img, 0, 0);
canvas_context.globalCompositeOperation = "destination-in";
canvas_context.drawImage(msk, 0, 0);
canvas_context.globalCompositeOperation = "source-over";
};
msk.src = 'WAVEFORM_IMAGE.EXT';
}
img.src = 'OVERLAY_IMAGE.EXT';
document.body.appendChild(canvas);
});
I think I understand what you mean. You want to change the color of the waveform background, the gray stuff around the waveform:
The problem here is that waveforms you get from SoundCloud API are represented as partly transparent PNG images, where waveform itself is transparent and the chrome around it is gray (#efefef) color.
So, unless the library you want to use for waveform customisation is using HTML5 canvas, you won't be able to use change the color of that chrome (so no, not possible with either HTML5 Widget API or Custom Player API). And you have to use waveform.js or the likes (or modify the waveform image on canvas yourself).
You could try to experiment with newest CSS filters (webkit only for now) and SVG filters, and possibly some MS IE filters for older IE versions, but I am not sure you'd manage to just change the color.
given a PDF that is rendered in the browser using pdfjs, are there functions to do the following basic view operations:
rotate
flip
zoom
If not, what are the best strategies I can use to do the operations above?
You can set rotation when you getting viewport form PdfPage object:
var viewport = pdfPage.getViewport(scale, rotation);
If you want to immediately set all the parameters, you can clone viewport, created with scale = 1:
var defaultViewport = pdfPage.getViewport(1);
var neededViewport = defaultViewport.clone({scale: needScale, rotation: needRotation, dontFlip: true});