I have a sprite sheet that I want to create a background from, but I want to generate it randomly from separate parts of the sheet. I'd rather not generate a full-sized image each time, as I don't want to have to store one for each session, can anyone help me?
I'm hoping it can be done with PHP but I'm not set on it. Any clues much appreciated.
The problem is getting "parts" of the sprite image and layering them. For this reason alone I'd be tempted not even consider CSS background images and go with layering everything on top of a htm5 canvas or svg or something. I guess you could separate the sprites beforehand, generate data uri variants (Mime encoded) and include it into your stylesheet that way (then the matter actually becomes trivial for modern browsers,as you can layer as many background images as you wish, all through CSS... well, except for the random positioning bit. That you'd have to do through either php or javascript.
Related
I am working on a project that consists of a online store, to sell Printed Circuit Boards.
But the hole system will be automated, and will be able to view online the Gerber files (Gerber are the files that has the machine code for the pcb).
I need to choose the best way to "output" this file uploaded by the user, to the webpage. Only for viewing the PCB before buying.
I have done the entire PHP code to process the Gerber, but, I can't decide if the file will be proccesed, and then:
I will save as a PNG file (rendering will be done with the PHP image library {that is a shit}), and if the user zoom, or do anything, it will not be perfect... (I would need to render in a high resolutiong, and would take a lot of space, and also time to load)
Render as an SVG file (Vector file), and show on the HTML as an mbeded element (Does it work on all new browsers? Is it slow to proccess?), The SVG file are awsome in terms of drawing lines...
And the last but not least way to doit, is to create a list of JavaScript commands, that draws on a Canvas Element (I have already implemented this, and works really good, but I don't like to think, that I'm actualy 'rendering' to a code...)
Anyway, what do you think I should use, and if I didn't tought in another way of doing it, please tell me!
Here is an example of the output as Canvas (With the source being a JavaScript function object, that has many drawLine commands):
I'm opting for SVG file, even if it's slower than canvas, but considering that won't be real time drawing process in terms of user interaction with the drawing object it's a good choice. SVG's are actually vectors, hence the images won't be crispy on large images. There are some quite good libraries out there which are working with svg-s like:
http://processingjs.org
http://d3js.org/
http://fabricjs.com/
http://raphaeljs.com/
I think d3 is one of the best. I definitely wont' recommend PHP image library.
I am trying different methods to turn an image into divs that represent each pixel.
One method has been using php imagecolorat to create divs with a background-color which works well.
However what if I had thousands of divs width:1px;height:1px; each with the same css background-image with incremented background position?
What performance hit would this have? Ie: does the browser draw the entire image many times or only the section that is visible as the background? Note the original image is several hundred kb.
Thanks
Only the section of the image should be drawn, however the drawing operation will be called as many times as the amount of pixels, so that will be a performance hit. Did you try writing any test code and measuring how it works?
Thousands of divs will hurt your performance no matter what, because the browser has to parse each div, add it to the DOM, then render it.
The actual performance will be different on different browsers. Only the part of the image being requested will be drawn, but the rendering function that draws the image will be called for EVERY div. It's more or less whether the specific browser's implementation can render one pixel of an image faster or parse a string and print the image. If the browser has the image in-memory, the difference might be moot. But if the browser has to open the image file every time, then the disk access will kill you.
That being said, I'm willing to bet there are better ways of doing what you are trying to do. You can get the pixel the mouse clicked/hovered/etc using JavaScript, and then add an absolute div at that specific point to create the "filter" you are talking about. Furthermore, if two pixels next to each other get tagged, you can just expand the former div, rather than creating a new one, which will help the performance by a lot
In other words, look into just loading the image with an img tag, and then using JavaScript to do what you are trying to do.
I'm trying to generate 3D isometric views of players' heads, but I'm not sure what kind of support PHP has for this type of operation, or of any external libraries that may be better suited.
Basically I need to take a net like this (here is a diagram showing what each portion is mapped to) and make a 3D head from it. I also need to include the 'head accessory' portions, which should be slightly larger/offset from the actual head.
Does anyone know how I should go about this?
Well first it will be a complex job in my view.
The http://www.minecraftwiki.net/images/0/01/Skinzones.png file you mentioned is flat, but you have to convert that in ISOMETRIC 3D look, so you have to distort the images
For example look at the images below
So you can see that 3D box image is created from the pieces of other images, the logic is to add perspective to the flat images and join them. but as it is 2D we will call it Image Distortion.
Unfortunately GD Library which comes bundled with PHP is not advanced enough to let you do such things.
You have to use some other library like Image Magic and this link is tutorial for using distort functions http://www.imagemagick.org/Usage/distorts/
Second big thing is the processing of the images, you can process the images live but it will consume lots of resources on server, so it is suggested that you use pre processed images, and not process them every time.
To generate the Isometric image you have to write the code your self, and it may need alteration on each image character depending upon the size of the image. But when you have written a code it will be easy.
My Suggestion is to write your own code once, then alter it for every character and save the processed images in a sprite and use them when you add play functionality.
check out this link as well
http://www.fmwconcepts.com/imagemagick/index.php
I'm trying to figure out via PHP if I can do the following. Imagine I have a two images. The first is an image of a square (50px by 50px). The second image, is that exact same square, only offset by 5px to the left.
I'm wondering if there is a way to dynamically generate all the images in-between to make this a smooth looking image transition (ie in this case generate the other 4 images to make it look like it moved from left to right). This would be a pretty simple situation, however would be applied to more complex images with the exact same premises, essentially using two images to predict the mediums.
Thank you in advance for your help
php would only be a wrapper, think eval() and google it, like http://www.linuxfocus.org/English/September2001/article139.shtml
regards,
/t
I believe the best thing you could hope to do with PHP is to do a 'morph' animation, where you sample the pixels for the first image and the second image, then create a third image consisting of the average color values. Repeating this process you could create as many sub-frames as you would like, but the result would be a blurring / morphing of image A -> image B, and would only be perceived as an animation with the simplest of input images.
More complicated algorithms including edge-detection or hinted-shape tweening could be utilized and implemented, however PHP might not be the best choice for this.
You can dynamically create images with a combination of PHP and ImageMagick.
You can pass in each dimension to ImageMagick, and it will generate an image on the fly for you. Create an image for each pixel you offset, resulting (in this case) in four extra images you can use later for your animation.
I was wondering if it was possible if I had an image like:
I would be able to change certain parts of the images colors. For example if I wanted the bow green and the present red with yellow stripes, would I have to make a new image that had that or is there a way to program something (elegantly) along the lines of that? I'm just asking to see if its possible and if it is, what language would be best to do this?
Keep in mind this would be a feature on a website.
That's not going to be easy the way the image is. You have no way to tell the computer which part is the bow, which part is the stripes, and which part is the box. However, if you pre-colored them, you could do a color replace using GD library or imagemagick pretty easily. You'd do this in PHP. Here are some examples of how you could do it, I'd personally go the imagemagick route.
How can I replace one color with another in a png 24 alpha transparent image with GD
http://www.imagemagick.org/Usage/color_basics/#replace
(this example even has a similar gift box as the usage case, hehe)
Try leaving the parts you want changable transparent. Then, give the div it's in a hover state with the second background color.
You could:
Use an indexed-color image and change the colors in the palette.
Use #MT's suggestion, though it kinda gets out of hand with multiple colors and jagged regions.
Pick control points and fill ("floodfill") the image through them - programmatic version of using the bucket tool.
Use #profitphp's suggestion, which is really better my last one.
Abandon compatibility and use the new canvas element while it still has the "cool" factor :)
i presume this is a web-based painting application; you'll require a human to tell you what the parts are, and where they want the coloring to be.
The issue then becomes how to perform a flood fill at the user's request.
The best i can suggest is perform the flood fill server-side, using an image processing library - handing back the image to the user:
There is no javascript ability to access pixel data of an image.
Edit: Performing flood fill with HTML Canvas