When I run my code, my white box does not appear. I need a white box to cover existing images, text, so I can add new text. If I change the color to background_color: [255,255,180], the box is a transparent yellow. However, I need a non-transparent white.
require 'hexapdf'
require 'pry'
doc = HexaPDF::Document.open('template.pdf')
pages = doc.pages
box = HexaPDF::Layout::Box.create(
width: 500, height: 500, content_box: true,
background_color: [255,255,255]
)
pages.each do |p|
canvas = p.canvas(type: :underlay)
box.draw(canvas, 20, 100)
end
doc.write("template_with_white_box.pdf")
You need to use canvas = p.canvas(type: :overlay) for this to work because the underlay canvas draws beneath the existing page whereas the overlay canvas draws above the existing page.
Related
I have an imageviewer with a couple images, When i zoom in the first image and wanna see the right side of the image. The folowing image is overlapping the inzooming image. This is very annoying. Is there a way how i can set the zoom in image on the front.
How can i set the zoomed image always on front.
See picture https://i.stack.imgur.com/5f5JZ.jpg
My imageviewer is in a container
Image red ;
red = EncodedImage.create("/HW_Delfzijl_Waddenzee_Oost.jpg");
Image blue = Image.createImage(500, 500, 0xff0000ff);
Image red2 = Image.createImage(500, 500, 0xffff0000);
Image List1[]= new Image [3];
List1[0] = red;
List1[1] = blue;
List1[2] = red2;
iv = new ImageViewer();
iv.setWidth(500);
iv.setHeight(500);
iv.setImageList(new DefaultListModel<>(List1));
Container1 = BoxLayout.encloseY( Kaarten.AuvHW, AdvSpr,iv,
Up,progressbar);
I was able to reproduce this with the following code:
Form hi = new Form("ImageViewer", BoxLayout.y());
Image red = Image.createImage(2000, 800, 0xffff0000);
Image blue = Image.createImage(2000, 500, 0xff0000ff);
ImageViewer viewer = new ImageViewer();
viewer.setImageList(new DefaultListModel<>(red, blue));
hi.add(BoxLayout.encloseY(viewer, new Label("Dummy")));
hi.show();
The problem only happens if I stand on the blue image (the second one) scale it up and then try to move. It doesn't happen when moving from the red image to the blue.
I believe this is due to this method in the ImagaViewer code. Since background isn't painted the old image isn't cleaned up. We need to add a condition that disables that while dragging. I think changing the code in that method to this will fix the problem but it's a bit risky and might trigger flickering:
protected void paintBackground(Graphics g) {
// disable background painting for performance when zooming
if(imageDrawWidth < getWidth() || imageDrawHeight < getHeight() || panPositionX != 0) {
super.paintBackground(g);
}
}
I would suggest filing an issue so we can consider the options here as this isn't trivial. One partial workaround is to use:
viewer.setImageInitialPosition(ImageViewer.IMAGE_FILL);
Which minimizes the impact of the issue.
I have a free form image with transparency (let's say, a small image of a blue car). The image has transparency, so that I can place the car on the map of a game.
Now, some areas of the game map are bluish, and the car kinda blends in. Is it possible to add a white border automatically in QML? I can't use GIMP or other things to work directly on the image (and I have lots of such images to manipulate) so it would be awesome if there was a QML builtin functionality for this...
In situations like this, a drop shadow is a good way of making an item standout. You normally would make it black or white based on the opposite of the average gray level of the image content itself.
It's pretty easy to add a DropShadow to an Image. This example places a nice light black drop shadow onto an image.
import QtGraphicalEffects 1.0
Image {
source: "my_image.png"
layer.enabled: true
layer.effect: DropShadow {
verticalOffset: 3
horizontalOffset: 0
radius: 8
color: "#26000000"
}
}
For more info see: https://doc.qt.io/qt-5/qml-qtgraphicaleffects-dropshadow.html
If you want a centered box shadow instead, just use a Rectangle somewhat like this:
Rectangle {
layer.enabled: true
layer.effect: DropShadow {
radius: 8
color: "#26000000"
}
Image {
source: "my_image.png"
}
}
Or if you just want a white border only:
Rectangle {
color: "transparent"
border.color: "white"
border.width: 2
Image {
source: "my_image.png"
}
}
In iText 7.1.9 I am taking a pdf created programmatically (not via iText) and need to apply a transparent rectangle along the left side and bottom to ensure the no content exists within a predefined clear zone (for print).
The below code places the yellow rectangles correctly but the desired result is the for the yellow fill to be semi-transparent or not 100% opaque so that visual inspection will show the content that that intersects with the rectangle instead of the rectangle clipping the content.
var page = pdf.GetPage(1);
PdfCanvas canvas = new PdfCanvas(page);
canvas.SaveState();
canvas.SetFillColor(iText.Kernel.Colors.ColorConstants.YELLOW);
var pageHeight = page.GetPageSize().GetHeight();
var pageWidth = page.GetPageSize().GetWidth();
// left side
canvas.Rectangle(0, 0, 15, pageHeight);
// bottom
canvas.Rectangle(0, 0, pageWidth, 15);
canvas.Fill();
canvas.RestoreState();
I attempted to use a TransparentColor but canvas.SetFillColor won't accept a TransparentColor, are there any other options?
When we speak about low-level content stream instructions, color itself and transparency levels are specified separately in PDF syntax. The TransparentColor class that you speak about was designed to simplify lives of users who are less familiar with nuances of PDF syntax, but it it a higher-level class that you can use e.g. in layout module, and in your case you operate with the document on quite low level.
Long story short, to set color transparency you only need one additional line next to setting the color itself:
canvas.SetExtGState(new PdfExtGState().SetFillOpacity(0.5f));
So the code becomes:
var page = pdf.GetPage(1);
PdfCanvas canvas = new PdfCanvas(page);
canvas.SaveState();
canvas.SetFillColor(iText.Kernel.Colors.ColorConstants.YELLOW);
canvas.SetExtGState(new PdfExtGState().SetFillOpacity(0.5f));
var pageHeight = page.GetPageSize().GetHeight();
var pageWidth = page.GetPageSize().GetWidth();
// left side
canvas.Rectangle(0, 0, 15, pageHeight);
// bottom
canvas.Rectangle(0, 0, pageWidth, 15);
canvas.Fill();
canvas.RestoreState();
I am trying to add an image as a background of a button in pygame gui. I have the button created now and I just need to add the image. How can I add the image to the button?
This is my code
game1 = pygame.Rect(150 , 100, 200, 150) # creates a rect object
pygame.draw.rect(screen, [255, 100, 0], game1) # draw objects down here
it works fine
You're probably looking for pygame.Surface.blit (http://www.pygame.org/docs/ref/surface.html#pygame.Surface.blit)
Load your background image and blit it wherever you want.
img = pygame.image.load('thisisanimage.png')
WhateverYourDisplayNameIs.blit(img,(x,y))
Just in case you're confused, it looks like you're using screen as your display surface.
I am working on a game using EaselJS, and I am still trying the functions provided by this great library.
What I may need is Alphamaskfilter class & Spritesheet class.
Currently, I have a canvas like this:
<canvas id = 'container3' width = 320px; height = 480px;
style = 'outline: 2px solid; margin-right: 10px;float:left;'></canvas>
and in my script, I have draw a rect with blue color:
var ctx3 = document.getElementById('container3').getContext('2d');
ctx3.beginPath();
ctx3.rect(0,0,320,480);
ctx3.fillStyle = 'blue';
ctx3.fill();
So now I have a blue color 320*480 canvas. And now I have a sprite sheet to animate on it,
here is the sprite and code I wrote:
http://i.imgur.com/XumDvic.png
PS: the sprite frame is 200*200 FYI.
stage = new createjs.Stage(document.getElementById('container3'));
var test = new Image();
test.src = 'trans_blackball.png';
test.onload = function(){
var sprite = new createjs.SpriteSheet({
images: [test],
frames: {width: 200, height: 200},
animations: {
born: [0,3,0]
}
});
var animation = new createjs.BitmapAnimation(sprite);
animation.gotoAndPlay("born");
animation.x = 10;
animation.y = 10;
animation.currentFrame = 0;
stage.addChild(animation);
createjs.Ticker.addListener(window);
createjs.Ticker.useRAF = true;
createjs.Ticker.setFPS(10);
}
function tick(){
stage.update();
}
Okay, my question is: I expect an animation of an enlarging black circle on a blue background(rect), but what I got is firstly the canvas is blue, but for a certain mini-second after, the whole canvas became white, and the animation is running on the white background, what is the reason of this and how can I solve it?
Here is two points that may help:
I am working with chrome, and I check with F12 & console, the fillStyle of the canvas is still blue even it appears white after the sprite animation start
If I set the canvas background property to blue instead of drawing a blue rect on it, everything's fine!!
<canvas id = 'container3' width = 320px; height = 480px;
style = 'background: blue; outline: 2px solid; margin-right:
10px;float:left;'></canvas>
but clearly this is not what I want...
The problem can be solved as well by not using native canvas rect but use EaselJS's Shape to draw the rect:
var shape = new createjs.Shape();
shape.graphics.beginFill("#ff0000").drawRect(0, 0, 320, 480);
stage.addChild(shape);
But I still wanna know why the native rect drawing code is not working...
Please bare my bad english and thanks for reading and any attempt to help...I can elaborate more if there is anything unclear in the situation..thanks!
createjs.Stage.update() will clear the canvas-contents by default before rendering the new frame.
The reason for this is one the one hand the technical behaviour of canvas, the canvas is basically just an image of pixels, you cannot have real 'layers' and say "I just want to remove/update this one object" - you just can modify the flattened pixels of the frame or remove everything and redraw it(which is safer, easier to achieve, and actually fast enough performance-whise. And on the other hand, it makes sense to make consistent use of a framework like EaselJS, and not do some parts with the framework and some parts without it, this would result in a big mess at the end.
So, the right solution is to go with 3.
You can set myStage.autoClear = false; to prevent the Stage from autoClearing the canvas on every update() but I don't think this will suit your needs in this case.
I would recommend instead using the EaselJS Shape class to make your blue box. If it part of the EaselJS display list, it will be drawn with the other content.
javascript
var shape = new createjs.Shape();
shape.graphics.beginFill("blue").drawRect(0,0,320,480);
stage.addChild(shape);