--- a/lib/HeatMap.php +++ b/lib/HeatMap.php @@ -1,1 +1,275 @@ - +<?php +/* +*DISCLAIMER +* http://blog.gmapify.fr/create-beautiful-tiled-heat-maps-with-php-and-gd +*THIS SOFTWARE IS PROVIDED BY THE AUTHOR 'AS IS' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES *OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, *INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF *USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT *(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +* +* @author: Olivier G. <olbibigo_AT_gmail_DOT_com> +* @version: 1.0 +* @history: +* 1.0 creation +*/ + define('PI2', 2*M_PI); + + class HeatMapPoint{ + public $x,$y; + function __construct($x,$y) { + $this->x = $x; + $this->y = $y; + } + function __toString() { + return "({$this->x},{$this->y})"; + } + }//Point + + class HeatMap{ + //TRANSPARENCY + public static $WITH_ALPHA = 0; + public static $WITH_TRANSPARENCY = 1; + //GRADIENT STYLE + public static $GRADIENT_CLASSIC = 'classic'; + public static $GRADIENT_FIRE = 'fire'; + public static $GRADIENT_PGAITCH = 'pgaitch'; + //GRADIENT MODE (for heatImage) + public static $GRADIENT_NO_NEGATE_NO_INTERPOLATE = 0; + public static $GRADIENT_NO_NEGATE_INTERPOLATE = 1; + public static $GRADIENT_NEGATE_NO_INTERPOLATE = 2; + public static $GRADIENT_NEGATE_INTERPOLATE = 3; + //NOT PROCESSED PIXEL (for heatImage) + public static $KEEP_VALUE = 0; + public static $NO_KEEP_VALUE = 1; + //CONSTRAINTS + private static $MIN_RADIUS = 2;//in px + private static $MAX_RADIUS = 50;//in px + private static $MAX_IMAGE_SIZE = 10000;//in px + + //generate an $image_width by $image_height pixels heatmap image of $points + public static function createImage($data, $image_width, $image_height, $mode=0, $spot_radius = 30, $dimming = 75, $gradient_name = 'classic'){ + $_gradient_name = $gradient_name; + if(($_gradient_name != self::$GRADIENT_CLASSIC) && ($_gradient_name != self::$GRADIENT_FIRE) && ($_gradient_name != self::$GRADIENT_PGAITCH)){ + $_gradient_name = self::$GRADIENT_CLASSIC; + } + $_image_width = min(self::$MAX_IMAGE_SIZE, max(0, intval($image_width))); + $_image_height = min(self::$MAX_IMAGE_SIZE, max(0, intval($image_height))); + $_spot_radius = min(self::$MAX_RADIUS, max(self::$MIN_RADIUS, intval($spot_radius))); + $_dimming = min(255, max(0, intval($dimming))); + if(!is_array($data)){ + return false; + } + $im = imagecreatetruecolor($_image_width, $_image_height); + $white = imagecolorallocate($im, 255, 255, 255); + imagefill($im, 0, 0, $white); + if(self::$WITH_ALPHA == $mode){ + imagealphablending($im, false); + imagesavealpha($im,true); + } + //Step 1: create grayscale image + foreach($data as $datum){ + if( (is_array($datum) && (count($datum)==1)) || (!is_array($datum) && ('HeatMapPoint' == get_class($datum)))){//Plot points + if('HeatMapPoint' != get_class($datum)){ + $datum = $datum[0]; + } + self::_drawCircularGradient($im, $datum->x, $datum->y, $_spot_radius, $_dimming); + }else if(is_array($datum)){//Draw lines + $length = count($datum)-1; + for($i=0; $i < $length; ++$i){//Loop through points + //Bresenham's algorithm to plot from from $datum[$i] to $datum[$i+1]; + self::_drawBilinearGradient($im, $datum[$i], $datum[$i+1], $_spot_radius, $_dimming); + } + } + } + //Gaussian filter + if($_spot_radius >= 30){ + imagefilter($im, IMG_FILTER_GAUSSIAN_BLUR); + } + //Step 2: create colored image + if(FALSE === ($grad_rgba = self::_createGradient($im, $mode, $_gradient_name))){ + return FALSE; + } + $grad_size = count($grad_rgba); + for($x=0; $x <$_image_width; ++$x){ + for($y=0; $y <$_image_height; ++$y){ + $level = imagecolorat($im, $x, $y) & 0xFF; + if( ($level >= 0) && ($level < $grad_size) ){ + imagesetpixel($im, $x, $y, $grad_rgba[imagecolorat($im, $x, $y) & 0xFF]); + } + } + } + if(self::$WITH_TRANSPARENCY == $mode){ + imagecolortransparent($im, $grad_rgba[count($grad_rgba)-1]); + } + return $im; + }//createImage + + //Heat an image + public static function heatImage($filepath, $gradient_name = 'classic', $mode= 0, $min_level=0, $max_level=255, $gradient_interpolate=0, $keep_value=0){ + $_gradient_name = $gradient_name; + if(($_gradient_name != self::$GRADIENT_CLASSIC) && ($_gradient_name != self::$GRADIENT_FIRE) && ($_gradient_name != self::$GRADIENT_PGAITCH)){ + $_gradient_name = self::$GRADIENT_CLASSIC; + } + $_min_level = min(255, max(0, intval($min_level))); + $_max_level = min(255, max(0, intval($max_level))); + + //try opening jpg first then png then gif format + if(FALSE === ($im = @imagecreatefromjpeg($filepath))){ + if(FALSE === ($im = @imagecreatefrompng($filepath))){ + if(FALSE === ($im = @imagecreatefromgif($filepath))){ + return FALSE; + } + } + } + if(self::$WITH_ALPHA == $mode){ + imagealphablending($im, false); + imagesavealpha($im,true); + } + $width = imagesx($im); + $height = imagesy($im); + if(FALSE === ($grad_rgba = self::_createGradient($im, $mode, $_gradient_name))){ + return FALSE; + } + //Convert to grayscale + $grad_size = count($grad_rgba); + $level_range = $_max_level - $_min_level; + for($x=0; $x <$width; ++$x){ + for($y=0; $y <$height; ++$y){ + $rgb = imagecolorat($im, $x, $y); + $r = ($rgb >> 16) & 0xFF; + $g = ($rgb >> 8) & 0xFF; + $b = $rgb & 0xFF; + $gray_level = Min(255, Max(0, floor(0.33 * $r + 0.5 * $g + 0.16 * $b)));//between 0 and 255 + if( ($gray_level >= $_min_level) && ($gray_level <= $_max_level) ){ + switch($gradient_interpolate){ + case self::$GRADIENT_NO_NEGATE_NO_INTERPOLATE: + //$_max_level takes related lowest gradient color + //$_min_level takes related highest gradient color + $value = 255 - $gray_level; + break; + case self::$GRADIENT_NEGATE_NO_INTERPOLATE: + //$_max_level takes related highest gradient color + //$_min_level takes related lowest gradient color + $value = $gray_level; + break; + case self::$GRADIENT_NO_NEGATE_INTERPOLATE: + //$_max_level takes lowest gradient color + //$_min_level takes highest gradient color + $value = 255- floor(($gray_level - $_min_level) * $grad_size / $level_range); + break; + case self::$GRADIENT_NEGATE_INTERPOLATE: + //$_max_level takes highest gradient color + //$_min_level takes lowest gradient color + $value = floor(($gray_level - $_min_level) * $grad_size / $level_range); + break; + default: + } + imagesetpixel($im, $x, $y, $grad_rgba[$value]); + }else{ + if(self::$KEEP_VALUE == $keep_value){ + //Do nothing + }else{//self::$NO_KEEP_VALUE + imagesetpixel($im, $x, $y, imagecolorallocatealpha($im,0,0,0,0)); + } + } + } + } + if(self::$WITH_TRANSPARENCY == $mode){ + imagecolortransparent($im, $grad_rgba[count($grad_rgba)-1]); + } + return $im; + }//heatImage + + private static function _drawCircularGradient(&$im, $center_x, $center_y, $spot_radius, $dimming){ + $dirty = array(); + $ratio = (255 - $dimming) / $spot_radius; + for($r=$spot_radius; $r > 0; --$r){ + $channel = $dimming + $r * $ratio; + $angle_step = 0.45/$r; //0.01; + //Process pixel by pixel to draw a radial grayscale radient + for($angle=0; $angle <= PI2; $angle += $angle_step){ + $x = floor($center_x + $r*cos($angle)); + $y = floor($center_y + $r*sin($angle)); + if(!isset($dirty[$x][$y])){ + $previous_channel = @imagecolorat($im, $x, $y) & 0xFF;//grayscale so same value + $new_channel = Max(0, Min(255,($previous_channel * $channel)/255)); + imagesetpixel($im, $x, $y, imagecolorallocate($im, $new_channel, $new_channel, $new_channel)); + $dirty[$x][$y] = 0; + } + } + } + }//_drawCircularGradient + + private static function _drawBilinearGradient(&$im, $point0, $point1, $spot_radius, $dimming){ + if($point0->x < $point1->x){ + $x0 = $point0->x; + $y0 = $point0->y; + $x1 = $point1->x; + $y1 = $point1->y; + }else{ + $x0 = $point1->x; + $y0 = $point1->y; + $x1 = $point0->x; + $y1 = $point0->y; + } + + if( ($x0==$x1) && ($y0==$y1)){//check if same coordinates + return false; + } + $steep = (abs($y1 - $y0) > abs($x1 - $x0))? true: false; + if($steep){ + list($x0, $y0) = array($y0, $x0);//swap + list($x1, $y1) = array($y1, $x1);//swap + } + if($x0>$x1){ + list($x0, $x1) = array($x1, $x0);//swap + list($y0, $y1) = array($y1, $y0);//swap + } + $deltax = $x1 - $x0; + $deltay = abs($y1 - $y0); + $error = $deltax / 2; + $y = $y0; + if( $y0 < $y1){ + $ystep = 1; + }else{ + $ystep = -1; + } + $step = max(1, floor($spot_radius/ 3)); + for($x=$x0; $x<=$x1; ++$x){//Loop through x value + if(0==(($x-$x0) % $step)){ + if($steep){ + self::_drawCircularGradient(&$im, $y, $x, $spot_radius, $dimming); + }else{ + self::_drawCircularGradient(&$im, $x, $y, $spot_radius, $dimming); + } + } + $error -= $deltay; + if($error<0){ + $y = $y + $ystep; + $error = $error + $deltax; + } + } + }//_drawBilinearGradient + + private static function _createGradient($im, $mode, $gradient_name){ + //create the gradient from an image + if(FALSE === ($grad_im = imagecreatefrompng('gradient/'.$gradient_name.'.png'))){ + return FALSE; + } + $width_g = imagesx($grad_im); + $height_g = imagesy($grad_im); + //Get colors along the longest dimension + //Max density is for lower channel value + for($y=$height_g-1; $y >= 0 ; --$y){ + $rgb = imagecolorat($grad_im, 1, $y); + //Linear function + $alpha = Min(127, Max(0, floor(127 - $y/2))); + if(self::$WITH_ALPHA == $mode){ + $grad_rgba[] = imagecolorallocatealpha($im, ($rgb >> 16) & 0xFF, ($rgb >> 8) & 0xFF, $rgb & 0xFF, $alpha); + }else{ + $grad_rgba[] = imagecolorallocate($im, ($rgb >> 16) & 0xFF, ($rgb >> 8) & 0xFF, $rgb & 0xFF); + } + } + imagedestroy($grad_im); + unset($grad_im); + return($grad_rgba); + }//_createGradient + }//Heatmap +?>