com php-src: Fix #43475: Styled thick horizontal lines are scrambled: ext/gd/libgd/gd.c ext/gd/tests/bug43475.phpt ext/gd/tests/bug43475.png

Commit: 8aa511f1fc8123bba6107fa856b0b6bf298de87c Author: Christoph M. Becker <cmb@php.net> Wed, 15 Jun 2016 20:58:06 +0200 Parents: 8267a5fba75baf938306d1169807be57d646c6df Branches: PHP-5.6 PHP-7.0 master Link: http://git.php.net/?p=php-src.git;a=commitdiff;h=8aa511f1fc8123bba6107fa856b0b6bf298de87c Log: Fix #43475: Styled thick horizontal lines are scrambled Thick lines are drawn by gdImageFilledRectangle(), which iterates over the x ordinate first (Z order) to apply the style pattern. While this works fine for vertical and diagonal lines, it obviously fails for horizontal lines, which have to be iterated over in N order. To fix this bug, we introduce the helpers gdImageFilled(H|V)Rectangle(), which may be reused for other purposes as well. This is basically the same fix as libgd/libgd/c2b91dbc. Bugs: https://bugs.php.net/43475 Changed paths: M ext/gd/libgd/gd.c A ext/gd/tests/bug43475.phpt A ext/gd/tests/bug43475.png Diff: diff --git a/ext/gd/libgd/gd.c b/ext/gd/libgd/gd.c index 5170f4f..89c7dbd 100644 --- a/ext/gd/libgd/gd.c +++ b/ext/gd/libgd/gd.c @@ -1051,11 +1051,13 @@ void gdImageAABlend (gdImagePtr im) } } +static void _gdImageFilledHRectangle (gdImagePtr im, int x1, int y1, int x2, int y2, int color); + static void gdImageHLine(gdImagePtr im, int y, int x1, int x2, int col) { if (im->thick > 1) { int thickhalf = im->thick >> 1; - gdImageFilledRectangle(im, x1, y - thickhalf, x2, y + im->thick - thickhalf - 1, col); + _gdImageFilledHRectangle(im, x1, y - thickhalf, x2, y + im->thick - thickhalf - 1, col); } else { if (x2 < x1) { int t = x2; @@ -2120,10 +2122,53 @@ void gdImageRectangle (gdImagePtr im, int x1, int y1, int x2, int y2, int color) } } -void gdImageFilledRectangle (gdImagePtr im, int x1, int y1, int x2, int y2, int color) +static void _gdImageFilledHRectangle (gdImagePtr im, int x1, int y1, int x2, int y2, int color) { int x, y; + if (x1 == x2 && y1 == y2) { + gdImageSetPixel(im, x1, y1, color); + return; + } + + if (x1 > x2) { + x = x1; + x1 = x2; + x2 = x; + } + + if (y1 > y2) { + y = y1; + y1 = y2; + y2 = y; + } + + if (x1 < 0) { + x1 = 0; + } + + if (x2 >= gdImageSX(im)) { + x2 = gdImageSX(im) - 1; + } + + if (y1 < 0) { + y1 = 0; + } + + if (y2 >= gdImageSY(im)) { + y2 = gdImageSY(im) - 1; + } + + for (x = x1; (x <= x2); x++) { + for (y = y1; (y <= y2); y++) { + gdImageSetPixel (im, x, y, color); + } + } +} + +static void _gdImageFilledVRectangle (gdImagePtr im, int x1, int y1, int x2, int y2, int color) +{ + int x, y; if (x1 == x2 && y1 == y2) { gdImageSetPixel(im, x1, y1, color); @@ -2165,6 +2210,11 @@ void gdImageFilledRectangle (gdImagePtr im, int x1, int y1, int x2, int y2, int } } +void gdImageFilledRectangle (gdImagePtr im, int x1, int y1, int x2, int y2, int color) +{ + _gdImageFilledVRectangle(im, x1, y1, x2, y2, color); +} + void gdImageCopy (gdImagePtr dst, gdImagePtr src, int dstX, int dstY, int srcX, int srcY, int w, int h) { int c; diff --git a/ext/gd/tests/bug43475.phpt b/ext/gd/tests/bug43475.phpt new file mode 100644 index 0000000..b29b980 --- /dev/null +++ b/ext/gd/tests/bug43475.phpt @@ -0,0 +1,59 @@ +--TEST-- +Bug #43475 (Thick styled lines have scrambled patterns) +--SKIPIF-- +<?php + if (!extension_loaded('gd')) die("skip gd extension not available\n"); +?> +--FILE-- +<?php +require_once __DIR__ . '/similarity.inc'; + +function setStyleAndThickness($im, $color, $thickness) +{ + $style = array(); + $i = 0; + while ($i < 16 * $thickness) { + $style[$i++] = $color; + } + while ($i < 20 * $thickness) { + $style[$i++] = IMG_COLOR_TRANSPARENT; + } + while ($i < 28 * $thickness) { + $style[$i++] = $color; + } + while ($i < 32 * $thickness) { + $style[$i++] = IMG_COLOR_TRANSPARENT; + } + imagesetstyle($im, $style); + imagesetthickness($im, $thickness); +} + +$im = imagecreate(800, 800); +imagecolorallocate($im, 255, 255, 255); +$black = imagecolorallocate($im, 0, 0, 0); + +setStyleAndThickness($im, $black, 1); +imageline($im, 50, 250, 550, 250, IMG_COLOR_STYLED); +imageline($im, 550, 250, 550, 750, IMG_COLOR_STYLED); +imageline($im, 550, 750, 50, 250, IMG_COLOR_STYLED); + +setStyleAndThickness($im, $black, 2); +imageline($im, 100, 200, 600, 200, IMG_COLOR_STYLED); +imageline($im, 600, 200, 600, 700, IMG_COLOR_STYLED); +imageline($im, 600, 700, 100, 200, IMG_COLOR_STYLED); + +setStyleAndThickness($im, $black, 4); +imageline($im, 150, 150, 650, 150, IMG_COLOR_STYLED); +imageline($im, 650, 150, 650, 650, IMG_COLOR_STYLED); +imageline($im, 650, 650, 150, 150, IMG_COLOR_STYLED); + +setStyleAndThickness($im, $black, 6); +imageline($im, 200, 100, 700, 100, IMG_COLOR_STYLED); +imageline($im, 700, 100, 700, 600, IMG_COLOR_STYLED); +imageline($im, 700, 600, 200, 100, IMG_COLOR_STYLED); + +$ex = imagecreatefrompng(__DIR__ . '/bug43475.png'); +var_dump(calc_image_dissimilarity($ex, $im) < 1e-5); +?> +--EXPECT-- +bool(true) diff --git a/ext/gd/tests/bug43475.png b/ext/gd/tests/bug43475.png new file mode 100644 index 0000000..774270f Binary files /dev/null and b/ext/gd/tests/bug43475.png differ