imagelayereffect
An example to draw Lissajous Curve (http://en.wikipedia.org/wiki/Lissajous_curve):
x = a1 * cos(t/T1);
y = a2 * sin(t/T2);
You can easily modify the codes to create your own oscilloscope application!
<?php
header ("Content-type: image/png");
$T1 = 20;
$T2 = 30;
$myImage = @imagecreatetruecolor(640, 480)
or die("Cannot Initialize new GD image stream");
$text_color = imagecolorallocate($myImage, 255, 255, 224);
$poly_color = imagecolorallocate($myImage, 124, 120, 224);
//calculate x-value and y-value point by point
$points = array();
for ($i=0; $i<1000; $i=$i+1)
{
//define curve's function
$x = 310*cos($i/$T1); //define x-value
$y = 230*sin($i/$T2);//define y-value
//move the coordinate, append a point's x-value and y-value
$points[] = 320+$x; //x-value
$points[] = 240-$y; //y-value
}
//count points
$totalPoints = count($points)/2;
//drawing title
$title = "Final Plot ($totalPoints points)";
imagestring($myImage, 3, 5, 5, $title, $text_color);
/** drawing points one by one, notice if there
* are 10 points, we need to draw 9 lines:
* 1) point 0 to 1;
* 2) point 1 to 2;
* ...
* ...
* 9) point 8 to 9;
*/
for ($i=0; $i<$totalPoints-1; $i++)
{
imageLine($myImage, $points[2*$i], $points[1+2*$i], $points[2+2*$i], $points[3+2*$i], $poly_color);
}
//finalizing
imagepng($myImage);
imagedestroy($myImage);
?>
imageline
(PHP 4, PHP 5)
imageline — Χαράξτε μία γραμμή
Περιγραφή
int imageline
( resource $image
, int $x1
, int $y1
, int $x2
, int $y2
, int $color
)
Η συνάρτηση imageline() σχεδιάζει μία γραμμή από το σημείο x1 , y1 έως το x2 , y2 (πάνω αριστερά βρίσκεται το σημείο 0, 0) στην εικόνα im χρώματος color .
Ανατρέξτε επίσης στις: imagecreate() και imagecolorallocate().
add a note
User Contributed Notesimageline
huirong dot jin at gmail dot com
01-Feb-2008 08:10
01-Feb-2008 08:10
huirong dot jin at gmail dot com
31-Jan-2008 01:57
31-Jan-2008 01:57
An example to draw Amplitude Modulation curve: y = c * sin (x/a) * sin (x/b) . You can easily modify the codes to create your own oscilloscope application!
<?php
header ("Content-type: image/png");
$myImage = @imagecreatetruecolor(640, 480)
or die("Cannot Initialize new GD image stream");
$text_color = imagecolorallocate($myImage, 255, 255, 224);
$poly_color = imagecolorallocate($myImage, 124, 120, 224);
//calculate x-value and y-value point by point
$points = array();
for ($i=1; $i<640; $i=$i+1)
{
//define curve's function
$x = $i; //define x-value, which is $i itself
$y = 150*sin($x/80)*sin($x/5);//define y-value
//append a point's x-value and y-value
$points[] = $x; //x-value
$points[] = 240-$y; //y-value
}
//count points
$totalPoints = count($points)/2;
//drawing title
$title = "Final Plot ($totalPoints points)";
imagestring($myImage, 3, 5, 5, $title, $text_color);
/** drawing points one by one, notice if there
* are 10 points, we need to draw 9 lines:
* 1) point 0 to 1;
* 2) point 1 to 2;
* ...
* ...
* 9) point 8 to 9;
*/
for ($i=0; $i<$totalPoints-1; $i++)
{
imageLine($myImage, $points[2*$i], $points[1+2*$i], $points[2+2*$i], $points[3+2*$i], $poly_color);
}
//finalizing
imagepng($myImage);
imagedestroy($myImage);
?>
admin at xpmail dot net
30-Apr-2007 05:45
30-Apr-2007 05:45
example of a Simple grid...
bool imagegrid ( resource $image, int $width, int $Height, int $size, mixed $color )
<?php
Header("Content-type: image/png");
$Width=450;
$Height=450;
$img = ImageCreateTrueColor($Width, $Height);
$bg = imagecolorallocate($img, 255, 255, 255);
imagefill($img, 0, 0, $bg);
$grid = imagecolorallocate($img, 225, 245, 249);
imagesetstyle($img, array($bg, $grid));
imagegrid($img, $Width, $Height, 10, IMG_COLOR_STYLED);
//makegrid($img, $Width, $Height, 10, $grid);
ImagePNG($img);
ImageDestroy($img);
function imagegrid($image, $w, $h, $s, $color)
{
for($iw=1; $iw<$w/$s; $iw++){imageline($image, $iw*$s, 0, $iw*$s, $w, $color);}
for($ih=1; $ih<$h/$s; $ih++){imageline($image, 0, $ih*$s, $w, $ih*$s, $color);}
}
?>
Jonathan W.
27-Apr-2007 01:15
27-Apr-2007 01:15
I've modified the previous entry for drawing on a polar coordinate system to better represent angles based on a 360º whole circle bearing.
<?php
function imagepolarline($image,$x1,$y1,$length,$angle,$color)
{
$x2 = $x1 + sin( deg2rad($angle) ) * $length;
$y2 = $y1 + cos( deg2rad($angle+180) ) * $length;
imageline($image,$x1,$y1,$x2,$y2,$color);
}
?>
Ian B
07-Nov-2006 03:59
07-Nov-2006 03:59
Here's a function to plot a line on a polar coordinate system:
<?php
function imagepolarline($image,$x1,$y1,$length,$angle,$color)
{
$x2 = $x1 + sin( deg2rad($angle+90) ) * $length;
$y2 = $y1 + cos( deg2rad($angle+90) ) * $length;
imageline($image,$x1,$y1,$x2,$y2,$color);
}
?>
x1,y1 are the coordinates for the central point. If you want the orientation to be like a compass i.e. 90 degrees = East, 180 = South etc, then use the following:
$x2 = $x1 + cos( deg2rad($angle-90)) * $length;
$y2 = $y1 + sin( deg2rad($angle-90)) * $length;
pb_2001 at haefft dot de
04-Mar-2006 02:41
04-Mar-2006 02:41
This is a function to make a dotted line. It accepts (it actually requires) 7 parameters and returns 1 if everything went OK and 0 if there was a problem.
int imagelinedotted ( resource im, int x1, int y1, int x2, int y2, int dist, int col )
imagelinedotted() draws a line from x1, y1 to x2, y2 (top left is 0, 0) in image im of colour col where dist defines the distance (measured in pixels) between one dot and another.
<?php
function imagelinedotted ($im, $x1, $y1, $x2, $y2, $dist, $col) {
$transp = imagecolortransparent ($im);
$style = array ($col);
for ($i=0; $i<$dist; $i++) {
array_push($style, $transp); // Generate style array - loop needed for customisable distance between the dots
}
imagesetstyle ($im, $style);
return (integer) imageline ($im, $x1, $y1, $x2, $y2, IMG_COLOR_STYLED);
imagesetstyle ($im, array($col)); // Reset style - just in case...
}
?>
fatpratmatt at gmail dot com
30-Jan-2006 11:43
30-Jan-2006 11:43
Here is a function which draws lines that cross at a specific point [It may need some tweaking]:
<?php
// Image Cross by Matt Evans
// $im - image resource
// $x - x coordinate where the lines should cross
// $y - y coordinate where the lines should cross
// $size - the length of each line
// $colour - the colour of the cross
function imagecross($im, $x, $y, $size = 5, $colour) {
imageline($im, $x+$size/2, $y+$size/2, $x-$size/2, $y-$size/2, $colour);
imageline($im, $x-$size/2, $y+$size, $x+$size/2, $y-$size, $colour);
}
// Example
imagecross($im, 50, 50, 5, $crosscolour);
?>
21-Oct-2005 07:30
imageline coordinate variables are documented as int , a value in decimal format will be truncated.
This may be useful when, for example, applying a non-integer scaling factor in generating an image.
Care should be taken to ensure this does not create significant errors that affect the quality of the image. For example :
<?php
$x=0.00000000001;$y=100;
imageline($img,0,0,0,$y+$x);
imageline($img,0,0,0,$y-$x);
?>
the first line will be straight , the second will have a step. Use round() where appropriate.
meid at gmx dot at
07-Sep-2005 10:39
07-Sep-2005 10:39
Some simple code to draw lines with specific thickness using "imagefilledpolygon". Useful if your gdlib does not support "imagesetthickness".
<?
function dickelinie($img,$start_x,$start_y,$end_x,$end_y,$color,$thickness)
{
$angle=(atan2(($start_y - $end_y),($end_x - $start_x)));
$dist_x=$thickness*(sin($angle));
$dist_y=$thickness*(cos($angle));
$p1x=ceil(($start_x + $dist_x));
$p1y=ceil(($start_y + $dist_y));
$p2x=ceil(($end_x + $dist_x));
$p2y=ceil(($end_y + $dist_y));
$p3x=ceil(($end_x - $dist_x));
$p3y=ceil(($end_y - $dist_y));
$p4x=ceil(($start_x - $dist_x));
$p4y=ceil(($start_y - $dist_y));
$array=array(0=>$p1x,$p1y,$p2x,$p2y,$p3x,$p3y,$p4x,$p4y);
imagefilledpolygon ( $img, $array, (count($array)/2), $color );
}
// Example:
header ("Content-type: image/jpeg");
$img = ImageCreate (210, 210) or die("Cannot Initialize new GD image stream ");
$backgroundcolor = ImageColorAllocate ($img, 255, 255, 255);
$orange = ImageColorAllocate($img, 252, 102, 4);
dickelinie($img, 10, 10, 10, 200,$orange,2);
dickelinie($img, 10, 200, 200, 10,$orange,2);
dickelinie($img, 200, 10, 200, 200,$orange,2);
imagejpeg($img);
ImageDestroy($img);
?>
d [AT] sprid [DOT] de
06-Sep-2005 03:12
06-Sep-2005 03:12
Here my function do clear all problems. With this, you can draw firstly smooth lines (basic code adapted from code_couturier at graffiti dot net, with some performance changes). The special is, you can define the alpha-value of the line (0 = normal smooth line, 127 = fully transparent). Change whatever you want to make it better, but post your results ;)
<?php
/**
* function imageSmoothAlphaLine() - version 1.0
* Draws a smooth line with alpha-functionality
*
* @param ident the image to draw on
* @param integer x1
* @param integer y1
* @param integer x2
* @param integer y2
* @param integer red (0 to 255)
* @param integer green (0 to 255)
* @param integer blue (0 to 255)
* @param integer alpha (0 to 127)
*
* @access public
*
* @author DASPRiD <d@sprid.de>
*/
function imageSmoothAlphaLine ($image, $x1, $y1, $x2, $y2, $r, $g, $b, $alpha=0) {
$icr = $r;
$icg = $g;
$icb = $b;
$dcol = imagecolorallocatealpha($image, $icr, $icg, $icb, $alpha);
if ($y1 == $y2 || $x1 == $x2)
imageline($image, $x1, $y2, $x1, $y2, $dcol);
else {
$m = ($y2 - $y1) / ($x2 - $x1);
$b = $y1 - $m * $x1;
if (abs ($m) <2) {
$x = min($x1, $x2);
$endx = max($x1, $x2) + 1;
while ($x < $endx) {
$y = $m * $x + $b;
$ya = ($y == floor($y) ? 1: $y - floor($y));
$yb = ceil($y) - $y;
$trgb = ImageColorAt($image, $x, floor($y));
$tcr = ($trgb >> 16) & 0xFF;
$tcg = ($trgb >> 8) & 0xFF;
$tcb = $trgb & 0xFF;
imagesetpixel($image, $x, floor($y), imagecolorallocatealpha($image, ($tcr * $ya + $icr * $yb), ($tcg * $ya + $icg * $yb), ($tcb * $ya + $icb * $yb), $alpha));
$trgb = ImageColorAt($image, $x, ceil($y));
$tcr = ($trgb >> 16) & 0xFF;
$tcg = ($trgb >> 8) & 0xFF;
$tcb = $trgb & 0xFF;
imagesetpixel($image, $x, ceil($y), imagecolorallocatealpha($image, ($tcr * $yb + $icr * $ya), ($tcg * $yb + $icg * $ya), ($tcb * $yb + $icb * $ya), $alpha));
$x++;
}
} else {
$y = min($y1, $y2);
$endy = max($y1, $y2) + 1;
while ($y < $endy) {
$x = ($y - $b) / $m;
$xa = ($x == floor($x) ? 1: $x - floor($x));
$xb = ceil($x) - $x;
$trgb = ImageColorAt($image, floor($x), $y);
$tcr = ($trgb >> 16) & 0xFF;
$tcg = ($trgb >> 8) & 0xFF;
$tcb = $trgb & 0xFF;
imagesetpixel($image, floor($x), $y, imagecolorallocatealpha($image, ($tcr * $xa + $icr * $xb), ($tcg * $xa + $icg * $xb), ($tcb * $xa + $icb * $xb), $alpha));
$trgb = ImageColorAt($image, ceil($x), $y);
$tcr = ($trgb >> 16) & 0xFF;
$tcg = ($trgb >> 8) & 0xFF;
$tcb = $trgb & 0xFF;
imagesetpixel ($image, ceil($x), $y, imagecolorallocatealpha($image, ($tcr * $xb + $icr * $xa), ($tcg * $xb + $icg * $xa), ($tcb * $xb + $icb * $xa), $alpha));
$y ++;
}
}
}
} // end of 'imageSmoothAlphaLine()' function
?>
Tyron
02-May-2005 11:50
02-May-2005 11:50
// Here's a function for drawing a rotated gradient Rectangle (based on a previous note)
// Create An Image 255x255
$img = ImageCreateTrueColor(255, 255);
GradientRect($img,50,50,80,80,30);
ImagePng($img,"test.png");
ImageDestroy($img);
echo "<br><img src=\"test.png\">";
function GradientRect($img, $x1, $y1, $x2, $y2, $wdt) {
$alpha = atan2($y2-$y1,$x2-$x1);
$real_wdt = $wdt*sin($alpha);
$real_hgt = $wdt*cos($alpha);
echo "real wdt:".$real_wdt;
echo "<br>real hgt:".$real_hgt;
echo "<br>angle: ".($angle*180/pi());
$plotD = 0;
$i=0;
$dy = $real_hgt/$wdt;
$dx = $real_wdt/$wdt;
$drgb= 256/$wdt;
while($i++ < $wdt) {
// Draw a line and move it down and make it lighter to get the gradient effect
ImageLine($img, $x1-$i*$dx, $y1+$i*$dy, $x2-$i*$dx, $y2+$i*$dy, ImageColorAllocate($img, $i*$drgb, 0, 0));
ImageLine($img, $x1-$i*$dx+1, $y1+$i*$dy, $x2-$i*$dx+1, $y2+$i*$dy, ImageColorAllocate($img, $i*$drgb, 0, 0));
}
}
ajreading at classixshop dot com
23-Apr-2005 07:28
23-Apr-2005 07:28
<?php
// An easy bit of code showing how you can use the ImageLine() function to create gradients
// Create An Image 255x255
$img = ImageCreateTrueColor(255, 255);
$plotD = 0;
while($plotD < 256)
{
// Draw a line and move it down and make it lighter to get the gradient effect
ImageLine($img, 0, $plotD , 255, $plotD, ImageColorAllocate($img, $plotD, $plotD, $plotD));
$plotD++;
}
Header("Content-type: image/png");
ImagePng($img);
ImageDestroy($img);
?>
eviloverlord at gmail dot com
27-Jan-2005 07:50
27-Jan-2005 07:50
This code is used to draw a board of hexagons (for games, classes, etc.)
<?php
//Draws a hexagonal board
// User-defined values
$maxTiles = 7; //The number of tiles at the center (widest part) of the board
$minTiles = 4; //The number of tiles at the edges of the board
$side = 30; //The length of the sides of the tiles in pixels
$bgColor = array(0, 0, 0); //The background color in RGB format
$fgColor = array(255, 255, 255);//The foreground color in RGB format
//Calculated values
$widthInTiles = range($maxTiles, $minTiles); //In our example: 7, 6, 5, 4
$rowsInTiles = count($widthInTiles)*2-1; //the total number of rows on our board
$xSide = $side*sin(deg2rad(60)); //the length of the x-part of the angled sides
$ySide = $side*sin(deg2rad(30)); //the length of the y-part of the angled sides
$boardWidth = $xSide*$widthInTiles[0]*2; //The entire width of the board
$boardHeight = $rowsInTiles*($side + $ySide) + $ySide; //The entire height of the board
// create a blank image and allocate the foreground, background colors
$image = imagecreate($boardWidth, $boardHeight);
$bg = imagecolorallocate($image, $bgColor[0], $bgColor[1], $bgColor[2]);
$fg = imagecolorallocate($image, $fgColor[0], $fgColor[1], $fgColor[2]);
// draw the board
$row = 0;
foreach($widthInTiles as $tiles)
{
for ($i = 0; $i < $tiles+1; $i++)
{
$x1 = $row*$xSide + $i*$xSide*2;
$y1 = $boardHeight/2;
$y1Dif = ($side/2) + $row*($side+$ySide);
$x2 = $x1 + $xSide;
$y2 = $y1;
$y2Dif = $ySide;
$x3 = $x2 + $xSide;
if ($i < $tiles)
{
imageline($image, $x1, $y1 - $y1Dif, $x2, $y2 - $y1Dif - $y2Dif, $fg);
imageline($image, $x1, $y1 + $y1Dif, $x2, $y2 + $y1Dif + $y2Dif, $fg);
imageline($image, $x2, $y2 - $y1Dif - $y2Dif, $x3, $y1 - $y1Dif, $fg);
imageline($image, $x2, $y2 + $y1Dif + $y2Dif, $x3, $y1 + $y1Dif, $fg);
}
imageline($image, $x1, $y1 - $y1Dif, $x1, $y1 - $y1Dif + $side, $fg);
imageline($image, $x1, $y1 + $y1Dif, $x1, $y1 + $y1Dif - $side, $fg);
}
$row++;
}
// output the picture
header("Content-type: image/png");
imagepng($image);
imagedestroy($image);
?>
likavcan at NOSPAN sturak nospan dot sk
05-Jun-2004 03:56
05-Jun-2004 03:56
This function draws arrow.
function arrow($im, $x1, $y1, $x2, $y2, $alength, $awidth, $color) {
$distance = sqrt(pow($x1 - $x2, 2) + pow($y1 - $y2, 2));
$dx = $x2 + ($x1 - $x2) * $alength / $distance;
$dy = $y2 + ($y1 - $y2) * $alength / $distance;
$k = $awidth / $alength;
$x2o = $x2 - $dx;
$y2o = $dy - $y2;
$x3 = $y2o * $k + $dx;
$y3 = $x2o * $k + $dy;
$x4 = $dx - $y2o * $k;
$y4 = $dy - $x2o * $k;
imageline($im, $x1, $y1, $dx, $dy, $color);
imageline($im, $x3, $y3, $x4, $y4, $color);
imageline($im, $x3, $y3, $x2, $y2, $color);
imageline($im, $x2, $y2, $x4, $y4, $color);
}
Lionel Van Bemten
22-May-2004 03:41
22-May-2004 03:41
here is a code to draw a "degraded" ... :
<?
header("Content-type : image/jpeg");
$image = @ImageCreate(200, 100)
or die ("Erreur de cration de l'image");
$lignes_colorees = 1;
$couleur_fond = ImageColorAllocate($image, 255, 255, 255);
$rouge_depart = 100;
$vert_depart = 255;
$bleu_depart = 0;
$rouge_fin = 0;
$vert_fin = 100;
$bleu_fin = 0;
$lignes = 100; //nb de lignes de l'image
$vert_diff = $vert_fin - $vert_depart;
$vert1 = $vert_diff / $lignes;
$bleu_diff = $bleu_fin - $bleu_depart;
$bleu1 = $bleu_diff / $lignes;
$rouge_diff = $rouge_fin - $rouge_depart;
$rouge1 = $rouge_diff / $lignes;
while ($lignes_colorees <= 100)
{
$rouge2 = $lignes_colorees * $rouge1; $rouge3 = $rouge_depart + $rouge2;
$rouge = round($rouge3);
$vert2 = $lignes_colorees * $vert1;
$vert3 = $vert_depart + $vert2;
$vert = round($vert2);
$bleu2 = $lignes_colorees * $bleu1;
$bleu3 = $bleu_depart + $bleu2;
$bleu = round($bleu2);
$y1 = $lignes_colorees;
$y2 = $lignes_colorees;
$x1 = 1; $x2 = 200;
$couleur = ImageColorAllocate($image, $rouge, $vert, $bleu);
//dessine la ligne
ImageLine($image, $x1, $y1, $x2, $y2, $couleur); $lignes_colorees ++;
}
//dessine l'image
ImageJpeg($image);
?>
ruturaj_v at yahoo dot com
14-May-2004 08:48
14-May-2004 08:48
here is a function that helps you create arrows...
<?php
function get_arrowheads ($x1, $y1, $x2, $y2, $arrhead, $arrang) {
$debug = false;
define("INFINITE", 'INFINITE');
if (($x2-$x1)==0) {
if ($y1 == 0) {
$slope = 0;
} else {
$slope = INFINITE;
}
} else {
$slope = -($y2-$y1)/($x2-$x1);
}
//$slope = number_format($slope, 2, '.','');
if ($slope == 'INFINITE') {
$ang = 90;
} else {
$ang = atan ($slope);
$ang = ($ang * 180)/pi();
}
//$ang = number_format($ang, 2, '.', '');
//echo ($ang);
//exit;
//convert the angle
$arrang1 = ($ang - $arrang);
$arrangdeg1 = ($ang - $arrang);
//echo ($arrang1);exit;
$arrang1 = ($arrang1*pi())/180;
$arrang2 = ($ang + $arrang);
$arrangdeg2 = ($ang + $arrang);
$arrang2 = ($arrang2*pi())/180;
//echo ($arrang1);
$arx1 = (floor(cos($arrang1)*$arrhead));
$ary1 = (floor(sin($arrang1)*$arrhead));
$arx2 = (floor(cos($arrang2)*$arrhead));
$ary2 = (floor(sin($arrang2)*$arrhead));
if ($debug) {
echo ("Values of arx1.. before add/sub</br>");
echo ("$arx1,$ary1 $arx2,$ary2</br>");
}
if ($ang==0) {
if ($x2 > $x1) {
$arx1 = $x2 - $arx1; $ary1 = $y2 - $ary1;
$arx2 = $x2 - $arx2; $ary2 = $y2 - $ary2;
} elseif ($x2 < $x1) {
$arx1 = $x2 + $arx1; $ary1 = $y2 - $ary1;
$arx2 = $x2 + $arx2; $ary2 = $y2 - $ary2;
}
}
if ($ang > 0 && $ang < 90) {
if (($x2 > $x1) && ($y2 < $y1)) {
$arx1 = $x2 - $arx1; $ary1 = $y2 + $ary1;
$arx2 = $x2 - $arx2; $ary2 = $y2 + $ary2;
} elseif (($x2 < $x1) && ($y2 > $y1)) {
$arx1 = $x2 + $arx1; $ary1 = $y2 - $ary1;
$arx2 = $x2 + $arx2; $ary2 = $y2 - $ary2;
}
}
if ($ang==90) {
if (($y2 > $y1)) {
$arx1 = $x2 - $arx1; $ary1 = $y2 - $ary1;
$arx2 = $x2 - $arx2; $ary2 = $y2 - $ary2;
} elseif (($y2 < $y1)) {
$arx1 = $x2 - $arx1; $ary1 = $y2 + $ary1;
$arx2 = $x2 - $arx2; $ary2 = $y2 + $ary2;
}
}
if ($ang > -90 && $ang < 0) {
if (($x2 > $x1) && ($y2 > $y1)) {
$arx1 = $x2 - $arx1; $ary1 = $y2 + $ary1;
$arx2 = $x2 - $arx2; $ary2 = $y2 + $ary2;
} elseif (($x2 < $x1) && ($y2 < $y1)) {
$arx1 = $x2 + $arx1; $ary1 = $y2 - $ary1;
$arx2 = $x2 + $arx2; $ary2 = $y2 - $ary2;
}
}
if ($debug) {
echo ("Angle of line is (".$ang*180/pi().")</br>");
echo ("Angle of line1 is $arrangdeg1</br>");
echo ("Angle of line2 is $arrangdeg2</br>");
echo ("$arx1,$ary1 $x2,$y2</br>");
echo ("$arx2,$ary2 $x2,$y2");
exit;
}
$array_arrows = array (
'x1' =>$arx1,
'y1' => $ary1,
'x2' => $arx2,
'y2' => $ary2
);
return $array_arrows;
}
$x1 = 200; $y1 = 200;
$x2 = 400; $y2 = 100;
$arrhead = 15; //10px
$arrang = 10; //10 deg
$ar_arrws = get_arrowheads ($x1, $y1, $x2, $y2, $arrhead, $arrang);
$im = imagecreate (400, 400);
$w = imagecolorallocate ($im, 255, 255, 255);
$red = imagecolorallocate ($im, 255, 0, 0);
//creates the base line
imageline ($im, $x1, $y1, $x2, $y2, $green);
imageline ($im, $x1+1, $x2+1, $y1+1, $y2+1, $red);
imageline ($im, $x2, $y2, $ar_arrws['x1'], $ar_arrws['y1'], $green);
imageline ($im, $x2, $y2, $ar_arrws['x2'], $ar_arrws['y2'], $green);
?>
yl at sota dot ch
14-Apr-2004 09:44
14-Apr-2004 09:44
Simple function to create border for jpg-images:
function createImageBorder($imgName){
$img = substr($imgName, 0, -4); // remove fileExtension
$ext = ".jpg";
$quality = 95;
$borderColor = 255; // 255 = white
/*
a b
+-------------------------+
|
| IMAGE
|
+-------------------------+
c d
*/
$scr_img = imagecreatefromjpeg($img.$ext);
$width = imagesx($scr_img);
$height = imagesy($scr_img);
// line a - b
$abX = 0;
$abY = 0;
$abX1 = $width;
$abY1 = 0;
// line a - c
$acX = 0;
$acY = 0;
$acX1 = 0;
$acY1 = $height;
// line b - d
$bdX = $width-1;
$bdY = 0;
$bdX1 = $width-1;
$bdY1 = $height;
// line c - d
$cdX = 0;
$cdY = $height-1;
$cdX1 = $width;
$cdY1 = $height-1;
// DRAW LINES
imageline($scr_img,$abX,$abY,$abX1,$abY1,$borderColor);
imageline($scr_img,$acX,$acY,$acX1,$acY1,$borderColor);
imageline($scr_img,$bdX,$bdY,$bdX1,$bdY1,$borderColor);
imageline($scr_img,$cdX,$cdY,$cdX1,$cdY1,$borderColor);
// create copy from image
imagejpeg($scr_img, $img."_border.jpg", $quality);
imagedestroy($scr_img);
}
createImageBorder("myfile.jpg");
XxXoldsaltXxX at hotmail dot com
14-Feb-2004 10:50
14-Feb-2004 10:50
Script to draw a grid of lines, which make the entire side of the picture look like a quarter circle.. very cool :)
<?php
$img_disp = imagecreate(1000,1000);
$backcolor = imagecolorallocate($img_disp,0,0,0);
imagefill($img_disp,0,0,$backcolor);
$textcolor = imagecolorallocate($img_disp,255,0,0);
$x1 = 0;
$y1 = 0;
$x2 = 0;
$y2 = 1000;
for(;;){
$y1 = $y1 + 20;
$x2 = $x2 + 20;
imageline($img_disp,$x1,$y1,$x2,$y2,$textcolor);
if ($y1 == 1000){
break;
}
}
header("Content-type: image/png");
imagepng($img_disp); // Draw the image
imagedestroy($img_disp); // Delete the image from the server's memory
?>
mueller at inf dot ufsc dot br
05-Jan-2004 12:26
05-Jan-2004 12:26
an algorithm to draw a bezier spline
<?php
$segmentos =30;
$x=array(0,10,80,30);
$y=array(0,10,40,50);
function bezier($p,$steps){
$t = 1 / $steps;
$temp = $t * $t;
$ret = array();
$f = $p[0];
$fd = 3 * ($p[1] - $p[0]) * $t;
$fdd_per_2=3*($p[0]-2*$p[1]+$p[2])*$temp;
$fddd_per_2=3*(3*($p[1]-$p[2])+$p[3]-$p[0])*$temp*$t;
$fddd =