仮想グリッドの操作
実際の幅/高さ(例:600x800)だけでなく、グリッドの幅/高さ(例:10x10)を使用して新しい画像を作成します。次に、画像に仮想サイズと仮想位置を与えることができます。私が何を意味するのかをあなたに理解してもらうために、段階的にそれを作ろうとします。
まず第一に、このための環境が必要です。
class imageGrid
{
private $realWidth;
private $realHeight;
private $gridWidth;
private $gridHeight;
private $image;
public function __construct($realWidth, $realHeight, $gridWidth, $gridHeight)
{
$this->realWidth = $realWidth;
$this->realHeight = $realHeight;
$this->gridWidth = $gridWidth;
$this->gridHeight = $gridHeight;
// create destination image
$this->image = imagecreatetruecolor($realWidth, $realHeight);
// set image default background
$white = imagecolorallocate($this->image, 255, 255, 255);
imagefill($this->image, 0, 0, $white);
}
public function __destruct()
{
imagedestroy($this->image);
}
public function display()
{
header("Content-type: image/png");
imagepng($this->image);
}
}
$imageGrid = new imageGrid(800, 600, 10, 10);
$imageGrid->display();
これにより、美しい白い正方形が得られます。次に、画像を表示するためのグリッドが必要です。それは想像しにくいかもしれないので、表示してみましょう。
public function demoGrid()
{
$black = imagecolorallocate($this->image, 0, 0, 0);
imagesetthickness($this->image, 3);
$cellWidth = ($this->realWidth - 1) / $this->gridWidth; // note: -1 to avoid writting
$cellHeight = ($this->realHeight - 1) / $this->gridHeight; // a pixel outside the image
for ($x = 0; ($x <= $this->gridWidth); $x++)
{
for ($y = 0; ($y <= $this->gridHeight); $y++)
{
imageline($this->image, ($x * $cellWidth), 0, ($x * $cellWidth), $this->realHeight, $black);
imageline($this->image, 0, ($y * $cellHeight), $this->realWidth, ($y * $cellHeight), $black);
}
}
}
呼び出すことによって:
$imageGrid = new imageGrid(800, 600, 10, 10);
$imageGrid->demoGrid();
$imageGrid->display();
見える :

ここで、3x4の長方形を作成し、仮想メジャーの(2,5)に貼り付ける方法を知りたいと思います。長方形の実際のサイズと位置を取得する方法を検索する必要があります。
public function demoPutSquare($sizeW, $sizeH, $posX, $posY)
{
// Cell width
$cellWidth = $this->realWidth / $this->gridWidth;
$cellHeight = $this->realHeight / $this->gridHeight;
// Conversion of our virtual sizes/positions to real ones
$realSizeW = ($cellWidth * $sizeW);
$realSizeH = ($cellHeight * $sizeH);
$realPosX = ($cellWidth * $posX);
$realPosY = ($cellHeight * $posY);
// Getting top left and bottom right of our rectangle
$topLeftX = $realPosX;
$topLeftY = $realPosY;
$bottomRightX = $realPosX + $realSizeW;
$bottomRightY = $realPosY + $realSizeH;
// Displaying rectangle
$red = imagecolorallocate($this->image, 100, 0, 0);
imagefilledrectangle($this->image, $topLeftX, $topLeftY, $bottomRightX, $bottomRightY, $red);
}
呼び出すことによって:
$imageGrid = new imageGrid(800, 600, 10, 10);
$imageGrid->demoGrid();
$imageGrid->demoPutSquare(3, 4, 2, 5);
$imageGrid->display();
グリッドの(2,5)に配置された3x4の正方形を取得します。

もっと真剣に考えてみましょう。画像を貼り付けるための適切な対策があります。
public function putImage($img, $sizeW, $sizeH, $posX, $posY)
{
// Cell width
$cellWidth = $this->realWidth / $this->gridWidth;
$cellHeight = $this->realHeight / $this->gridHeight;
// Conversion of our virtual sizes/positions to real ones
$realSizeW = ceil($cellWidth * $sizeW);
$realSizeH = ceil($cellHeight * $sizeH);
$realPosX = ($cellWidth * $posX);
$realPosY = ($cellHeight * $posY);
// Copying the image
imagecopyresampled($this->image, $img, $realPosX, $realPosY, 0, 0, $realSizeW, $realSizeH, imagesx($img), imagesy($img));
}
呼び出すことによって:
$imageGrid = new imageGrid(800, 600, 10, 10);
$imageGrid->demoGrid();
$img = imagecreatefromjpeg("ninsuo.jpg");
$imageGrid->putImage($img, 3, 4, 2, 5);
$imageGrid->display();
我々が得る :

そうすれば、良い場所に写真ができますが、アスペクト比が失われます。画像のサイズを正しく変更するメソッドを追加しましょう。
public function resizePreservingAspectRatio($img, $targetWidth, $targetHeight)
{
$srcWidth = imagesx($img);
$srcHeight = imagesy($img);
$srcRatio = $srcWidth / $srcHeight;
$targetRatio = $targetWidth / $targetHeight;
if (($srcWidth <= $targetWidth) && ($srcHeight <= $targetHeight))
{
$imgTargetWidth = $srcWidth;
$imgTargetHeight = $srcHeight;
}
else if ($targetRatio > $srcRatio)
{
$imgTargetWidth = (int) ($targetHeight * $srcRatio);
$imgTargetHeight = $targetHeight;
}
else
{
$imgTargetWidth = $targetWidth;
$imgTargetHeight = (int) ($targetWidth / $srcRatio);
}
$targetImg = imagecreatetruecolor($targetWidth, $targetHeight);
imagecopyresampled(
$targetImg,
$img,
($targetWidth - $imgTargetWidth) / 2, // centered
($targetHeight - $imgTargetHeight) / 2, // centered
0,
0,
$imgTargetWidth,
$imgTargetHeight,
$srcWidth,
$srcHeight
);
return $targetImg;
}
そして直前:
imagecopyresampled($this->image, $img, $realPosX, $realPosY, 0, 0, $realSizeW, $realSizeH, imagesx($img), imagesy($img));
私たちは置きます:
$img = $this->resizePreservingAspectRatio($img, $realSizeW, $realSizeH);
これは次のようになります:

私たちは今あなたの仕事をするための完全な機能クラスを持っています。
class imageGrid
{
private $realWidth;
private $realHeight;
private $gridWidth;
private $gridHeight;
private $image;
public function __construct($realWidth, $realHeight, $gridWidth, $gridHeight)
{
$this->realWidth = $realWidth;
$this->realHeight = $realHeight;
$this->gridWidth = $gridWidth;
$this->gridHeight = $gridHeight;
// create destination image
$this->image = imagecreatetruecolor($realWidth, $realHeight);
$black = imagecolorallocate($this->image, 0, 0, 0);
imagecolortransparent($this->image, $black);
}
public function __destruct()
{
imagedestroy($this->image);
}
public function display()
{
header("Content-type: image/png");
imagepng($this->image);
}
public function putImage($img, $sizeW, $sizeH, $posX, $posY)
{
// Cell width
$cellWidth = $this->realWidth / $this->gridWidth;
$cellHeight = $this->realHeight / $this->gridHeight;
// Conversion of our virtual sizes/positions to real ones
$realSizeW = ceil($cellWidth * $sizeW);
$realSizeH = ceil($cellHeight * $sizeH);
$realPosX = ($cellWidth * $posX);
$realPosY = ($cellHeight * $posY);
$img = $this->resizePreservingAspectRatio($img, $realSizeW, $realSizeH);
// Copying the image
imagecopyresampled($this->image, $img, $realPosX, $realPosY, 0, 0, $realSizeW, $realSizeH, imagesx($img), imagesy($img));
}
public function resizePreservingAspectRatio($img, $targetWidth, $targetHeight)
{
$srcWidth = imagesx($img);
$srcHeight = imagesy($img);
$srcRatio = $srcWidth / $srcHeight;
$targetRatio = $targetWidth / $targetHeight;
if (($srcWidth <= $targetWidth) && ($srcHeight <= $targetHeight))
{
$imgTargetWidth = $srcWidth;
$imgTargetHeight = $srcHeight;
}
else if ($targetRatio > $srcRatio)
{
$imgTargetWidth = (int) ($targetHeight * $srcRatio);
$imgTargetHeight = $targetHeight;
}
else
{
$imgTargetWidth = $targetWidth;
$imgTargetHeight = (int) ($targetWidth / $srcRatio);
}
$targetImg = imagecreatetruecolor($targetWidth, $targetHeight);
imagecopyresampled(
$targetImg,
$img,
($targetWidth - $imgTargetWidth) / 2, // centered
($targetHeight - $imgTargetHeight) / 2, // centered
0,
0,
$imgTargetWidth,
$imgTargetHeight,
$srcWidth,
$srcHeight
);
return $targetImg;
}
}
これで、それが機能するかどうかを確認するために遊ぶことができます:
$imageGrid = new imageGrid(800, 400, 12, 2);
$blue = imagecreatefrompng("cheers_blue.png");
$imageGrid->putImage($blue, 6, 2, 0, 0);
imagedestroy($blue);
$green = imagecreatefrompng("cheers_green.png");
$imageGrid->putImage($green, 2, 1, 6, 0);
imagedestroy($green);
$red = imagecreatefrompng("cheers_red.png");
$imageGrid->putImage($red, 2, 1, 8, 0);
imagedestroy($red);
$yellow = imagecreatefrompng("cheers_yellow.png");
$imageGrid->putImage($yellow, 2, 1, 10, 0);
imagedestroy($yellow);
$purple = imagecreatefrompng("cheers_purple.png");
$imageGrid->putImage($purple, 3, 1, 6, 1);
imagedestroy($purple);
$cyan = imagecreatefrompng("cheers_cyan.png");
$imageGrid->putImage($cyan, 3, 1, 9, 1);
imagedestroy($cyan);
$imageGrid->display();

個人的には、アスペクト比を維持しないものが好きです:-)

乾杯!(ええ、私が言うことを楽しんでください!)