HTML kanvas globalCompositeOperation Property
Contoh
Gambar persegi panjang menggunakan dua nilai globalCompositeOperation yang berbeda. Persegi panjang merah adalah gambar tujuan . Persegi panjang biru adalah gambar sumber :
sumber-over
tujuan-over
JavaScript:
var c = document.getElementById("myCanvas");
var ctx = c.getContext("2d");
ctx.fillStyle = "red";
ctx.fillRect(20, 20, 75, 50);
ctx.globalCompositeOperation = "source-over";
ctx.fillStyle = "blue";
ctx.fillRect(50, 50, 75, 50);
ctx.fillStyle = "red";
ctx.fillRect(150, 20, 75, 50);
ctx.globalCompositeOperation = "destination-over";
ctx.fillStyle = "blue";
ctx.fillRect(180, 50, 75, 50);
Dukungan Peramban
Angka-angka dalam tabel menentukan versi browser pertama yang sepenuhnya mendukung properti.
Property | |||||
---|---|---|---|---|---|
globalCompositeOperation | 4.0 | 9.0 | 3.6 | 4.0 | 10.1 |
Definisi dan Penggunaan
Properti globalCompositeOperation menyetel atau mengembalikan cara gambar sumber (baru) digambar ke gambar tujuan (yang sudah ada).
source image = gambar yang akan Anda tempatkan ke kanvas.
gambar tujuan = gambar yang sudah ditempatkan di kanvas.
Nilai bawaan: | sumber-over |
---|---|
Sintaks JavaScript: | konteks .globalCompositeOperation = "sumber-dalam"; |
Nilai properti
Value | Description | Play it |
---|---|---|
source-over | Default. Displays the source image over the destination image | |
source-atop | Displays the source image on top of the destination image. The part of the source image that is outside the destination image is not shown | |
source-in | Displays the source image in to the destination image. Only the part of the source image that is INSIDE the destination image is shown, and the destination image is transparent | |
source-out | Displays the source image out of the destination image. Only the part of the source image that is OUTSIDE the destination image is shown, and the destination image is transparent | |
destination-over | Displays the destination image over the source image | |
destination-atop | Displays the destination image on top of the source image. The part of the destination image that is outside the source image is not shown | |
destination-in | Displays the destination image in to the source image. Only the part of the destination image that is INSIDE the source image is shown, and the source image is transparent | |
destination-out | Displays the destination image out of the source image. Only the part of the destination image that is OUTSIDE the source image is shown, and the source image is transparent | |
lighter | Displays the source image + the destination image | |
copy | Displays the source image. The destination image is ignored | |
xor | The source image is combined by using an exclusive OR with the destination image |
Contoh
Semua nilai properti globalCompositeOperation: