Black and white Pattern, Torn paper background, black and white abstract painting, angle, white png 3584x3417px 270.82KB.Computer file, Hand-drawn lines border, border, angle png 4899x3294px 168.57KB.background material the chemical structure, black and blue honeycomb, texture, png Material png 1213x931px 187.12KB.Texture mapping Paper, Retro paper particles superimposed background, texture, white png 5008圆935px 513.15KB.Wall, Black Crack, white, hand png 1035x1352px 288.38KB.Black and white Symmetry Daytime Pattern, Radioactive light effect, time-lapse grayscale, texture, triangle png 1000x1000px 496.14KB. Euclidean Technology, Technology creative material, blue and black abstract, texture, cdr png 1500x1500px 198.25KB.Triangle Black and white Pattern, Blue Technology Triangle, black graphic, texture, angle png 2409x2492px 177.2KB.The examples in function imagettfbbox() gave me many problems because of misunderstand of how the text is positionned in the box. Here is some example code to blank an image to transparent, assuming $im is a successfully created image: I would recommend using imagefilledrectangle() to create a blank transparent image resource instead of imagefill() because it is undoubtedly much faster in probably all cases. I suspect there are reasons for this to do with alpha channels complicating edge detection. I guess the reason imagefill() works with alpha blending on is because it does not perform any alpha blending - it always works without alpha blending regardless of the setting. So in order to use imagefilledrectangle() to erase an image to transparency, you need to turn off alpha blending first. So, drawing the rectangle in this case results in the original content of the image being completely replaced with a transparent rectangle. With blending off, when drawing to the image what you draw completely replaces what is already there. Therefore, because blending is on, and because the rectangle's fill colour is completely transparent, the blending of the existing image content with the transparent rectangle results in no change to the existing image. Alpha blending causes what you draw on the image to be blended with whatever is already on the image according to the alpha channels of each. The issue with filling using a rectangle is caused in your code by having alpha blending turned on before rendering the filled rectangle. If you need more performance, the step can be increased $inc_blue = ( $dest_blue - $src_blue )/ $width $inc_green = ( $dest_green - $src_green )/ $width $inc_red = ( $dest_red - $src_red )/ $width $inc_alpha = ( $dest_alpha - $src_alpha ) / $width I've made a function to make full color gradients: Getting Started Introduction A simple tutorial Language Reference Basic syntax Types Variables Constants Expressions Operators Control Structures Functions Classes and Objects Namespaces Enumerations Errors Exceptions Fibers Generators Attributes References Explained Predefined Variables Predefined Exceptions Predefined Interfaces and Classes Predefined Attributes Context options and parameters Supported Protocols and Wrappers Security Introduction General considerations Installed as CGI binary Installed as an Apache module Session Security Filesystem Security Database Security Error Reporting User Submitted Data Hiding PHP Keeping Current Features HTTP authentication with PHP Cookies Sessions Dealing with XForms Handling file uploads Using remote files Connection handling Persistent Database Connections Command line usage Garbage Collection DTrace Dynamic Tracing Function Reference Affecting PHP's Behaviour Audio Formats Manipulation Authentication Services Command Line Specific Extensions Compression and Archive Extensions Cryptography Extensions Database Extensions Date and Time Related Extensions File System Related Extensions Human Language and Character Encoding Support Image Processing and Generation Mail Related Extensions Mathematical Extensions Non-Text MIME Output Process Control Extensions Other Basic Extensions Other Services Search Engine Extensions Server Specific Extensions Session Extensions Text Processing Variable and Type Related Extensions Web Services Windows Only Extensions XML Manipulation GUI Extensions Keyboard Shortcuts ? This help j Next menu item k Previous menu item g p Previous man page g n Next man page G Scroll to bottom g g Scroll to top g h Goto homepage g s Goto search
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