| <?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 | |
| ?> |