VectorDrawable 渲染问题

VectorDrawable rendering issue

我在使用支持库引入的 VectorDrawables 时遇到问题。

环顾四周,我在 Android Studio 中了解到有关缩放比例不佳或预览不正确的类似问题。好吧,不幸的是我的问题不同。

问题:

事实上,我的 VectorDrawable 在 Android Studio 预览中呈现完美,但在设备运行时出现混乱(Android v. 5.1.1 和 6.0)。

正在导出:

从一个 SVG 文件(只有一个复合路径)开始,我使用 Android Studio 工具导入它(但我也尝试了许多其他工具来转换它)。 该文件的制作方式与其他一些文件相同,但只有一些渲染效果不佳。

我已经尝试过的:

我试图用 app:srcCompat 在图像视图中设置它(即使使用 src:)。 我试图在菜单中使用它(直接设置图标,或使用 选择器)。

SVG 代码:

<svg id="Layer_1" data-name="Layer 1" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 626.96 610.53"><title>PATHOLOGIES</title><path d="M5766.55,588.54a54.73,54.73,0,0,0-4.23-3.81,248.33,248.33,0,0,0,31.34-121.54c-0.23-138.68-114.72-251.15-253.38-249-134.71,2.07-243.52,110.91-245.54,245.64a249.48,249.48,0,0,0,390.59,209.52l0.21,0.22,155.12,155.12,81-81Zm-222.36,64.92c-104.85,0-189.85-85-189.85-189.85s85-189.85,189.85-189.85S5734,358.76,5734,463.61,5649,653.46,5544.19,653.46ZM5452,347.1l7.72-22.08a161.29,161.29,0,0,1,52.5-20.55l-19.84,56.75A19.25,19.25,0,0,1,5467.83,373l-4-1.41A19.25,19.25,0,0,1,5452,347.1Zm20.13,82.62L5430,502.57a19.25,19.25,0,0,1-26.29,7l-3.71-2.14a19.25,19.25,0,0,1-7-26.29L5435,408.33a19.25,19.25,0,0,1,26.29-7l3.71,2.14A19.25,19.25,0,0,1,5472.1,429.72Zm-82.73-14.9A161.59,161.59,0,0,1,5408.85,374l9.06,9.06a19.25,19.25,0,0,1,0,27.22l-3,3A19.24,19.24,0,0,1,5389.37,414.82Zm151.76-54A19.25,19.25,0,0,1,5552,335.85l55.51-21.72a162.36,162.36,0,0,1,43.87,27.64A19.17,19.17,0,0,1,5646,345l-78.34,30.65a19.25,19.25,0,0,1-24.94-10.91Zm-13.43,29.12,66.74,51.21a19.25,19.25,0,0,1,3.55,27l-2.61,3.4a19.25,19.25,0,0,1-27,3.55l-66.74-51.21a19.25,19.25,0,0,1-3.55-27l2.61-3.4A19.25,19.25,0,0,1,5527.69,389.91Zm83.57,191.47-2.82,3.23a19.25,19.25,0,0,1-27.15,1.86l-63.41-55.28A19.25,19.25,0,0,1,5516,504l2.82-3.23a19.25,19.25,0,0,1,27.16-1.86l63.41,55.28A19.25,19.25,0,0,1,5611.26,581.38Zm60.09-191.15,4,1.59a19.25,19.25,0,0,1,10.71,25l-31.28,78.09a19.25,19.25,0,0,1-25,10.71l-4-1.59A19.25,19.25,0,0,1,5615,479l31.28-78.09A19.25,19.25,0,0,1,5671.34,390.24ZM5504.73,604.39a19.19,19.19,0,0,1-4.85,15.4,161.36,161.36,0,0,1-38.43-16.53l-9.92-76.83a19.25,19.25,0,0,1,16.62-21.55l4.25-.55A19.25,19.25,0,0,1,5494,521ZM5686.4,538L5685,544.4a163.11,163.11,0,0,1-56.5,57.93l16.12-73.51a19.25,19.25,0,0,1,22.92-14.68l4.19,0.92A19.25,19.25,0,0,1,5686.4,538Z" transform="translate(-5294.72 -214.14)"/></svg>

矢量绘图代码:

<vector android:height="24dp" android:viewportHeight="610.53"
android:viewportWidth="626.96" android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
<path android:fillColor="#FF000000" android:pathData="M471.8,374.4a54.7,54.7 0,0 0,-4.2 -3.8,248.3 248.3,0 0,0 31.3,
-121.5c-0.2,-138.7 -114.7,-251.1 -253.4,-249 -134.7,2.1 -243.5,110.9 -245.5,245.6a249.5,249.5 0,0 0,390.6 209.5l0.2,
0.2 155.1,155.1 81,-81ZM249.5,439.3c-104.8,0 -189.9,-85 -189.9,-189.9s85,-189.9 189.9,-189.9S439.3,144.6 439.3,
249.5 354.3,439.3 249.5,439.3ZM157.3,133l7.7,-22.1a161.3,161.3 0,0 1,52.5 -20.5l-19.8,56.8A19.3,19.3 0,0 1,
173.1 158.9l-4,-1.4A19.3,19.3 0,0 1,157.3 133ZM177.4,215.6L135.3,288.4a19.3,19.3 0,0 1,-26.3 7l-3.7,-2.1a19.3,
19.3 0,0 1,-7 -26.3L140.3,194.2a19.3,19.3 0,0 1,26.3 -7l3.7,2.1A19.3,19.3 0,0 1,177.4 215.6ZM94.7,200.7A161.6,
161.6 0,0 1,114.1 159.9l9.1,9.1a19.3,19.3 0,0 1,0 27.2l-3,3A19.2,19.2 0,0 1,94.6 200.7ZM246.4,146.7A19.3,19.3 0,
0 1,257.3 121.7l55.5,-21.7a162.4,162.4 0,0 1,43.9 27.6A19.2,19.2 0,0 1,351.3 130.9l-78.3,30.6a19.3,19.3 0,0 1,
-24.9 -10.9ZM233,175.8 L299.7,227a19.3,19.3 0,0 1,3.5 27l-2.6,3.4a19.3,19.3 0,0 1,-27 3.5l-66.7,-51.2a19.3,19.3 0,
0 1,-3.5 -27l2.6,-3.4A19.3,19.3 0,0 1,233 175.8ZM316.6,367.3 L313.8,370.5a19.3,19.3 0,0 1,-27.1 1.9l-63.4,-55.3A19.3,
19.3 0,0 1,221.3 289.9l2.8,-3.2a19.3,19.3 0,0 1,27.2 -1.9l63.4,55.3A19.3,19.3 0,0 1,316.5 367.2ZM376.7,176.1 L380.7,
177.7a19.3,19.3 0,0 1,10.7 25l-31.3,78.1a19.3,19.3 0,0 1,-25 10.7l-4,-1.6A19.3,19.3 0,0 1,320.3 264.9l31.3,-78.1A19.3,
19.3 0,0 1,376.6 176.1ZM210,390.3a19.2,19.2 0,0 1,-4.8 15.4,161.4 161.4,0 0,1 -38.4,-16.5l-9.9,-76.8a19.3,19.3 0,0 1,
16.6 -21.5l4.3,-0.6A19.3,19.3 0,0 1,199.3 306.9ZM391.7,323.9L390.3,330.3a163.1,163.1 0,0 1,-56.5 57.9l16.1,-73.5a19.3,
19.3 0,0 1,22.9 -14.7l4.2,0.9A19.3,19.3 0,0 1,391.7 323.9Z"/>

在 Android Studio 上渲染:

在设备上呈现(AndroidStudio 导入后):

我真的无法弄清楚是什么导致了糟糕的渲染。我很确定这不是 svg 问题(如果我错了,请纠正我),因为其他可绘制对象正在正确渲染。我什至不会要求库错误,因为我恰好是唯一遇到问题的人。我做错了什么?

感谢您的帮助

我怀疑是路径命令解析的问题。如果我们查看您路径的第一个子路径(未正确绘制的子路径),它看起来如下所示:

M 471.8, 374.4
a 54.7, 54.7 0, 0 0, -4.2 -3.8,
  248.3 248.3, 0 0, 0 31.3,-121.5
c -0.2, -138.7 -114.7, -251.1 -253.4, -249
  -134.7, 2.1 -243.5, 110.9 -245.5, 245.6
a 249.5, 249.5 0, 0 0, 390.6 209.5
l 0.2, 0.2
  155.1, 155.1
  81, -81Z

为了便于阅读,我将其分解。

你可以看到它使用了 SVG 路径命令字符串的功能之一,如果路径命令重复,你可以跳过它,只提供坐标。它在这里为 a(圆弧)、c(曲线)和 l(线)命令执行此操作。

虽然线段(形成手柄)看起来渲染正常,但我怀疑 VectorDrawable 渲染器没有正确解析弧 and/or 曲线段。但是我还没有查看 Android 代码库来确认错误。

我建议您尝试将跳过的路径命令字符放回路径中,看看效果是否更好。例如:

M 471.8, 374.4
a 54.7, 54.7 0, 0 0, -4.2 -3.8
a 248.3 248.3, 0 0, 0 31.3,-121.5
c -0.2, -138.7 -114.7, -251.1 -253.4, -249
c -134.7, 2.1 -243.5, 110.9 -245.5, 245.6
a 249.5, 249.5 0, 0 0, 390.6 209.5
l 0.2, 0.2
  155.1, 155.1
  81, -81Z

字符串后面还有另一个子路径(对应于 "pills" 之一),它也使用重复坐标快捷方式。如果我们也修改它,生成的 VectorDrawable 看起来像:

<vector android:height="24dp" android:viewportHeight="610.53"
android:viewportWidth="626.96" android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
<path android:fillColor="#FF000000" android:pathData="M471.8,374.4a54.7,54.7 0,0 0,-4.2 -3.8a248.3 248.3,0 0,0 31.3,
-121.5c-0.2,-138.7 -114.7,-251.1 -253.4,-249c-134.7,2.1 -243.5,110.9 -245.5,245.6a249.5,249.5 0,0 0,390.6 209.5l0.2,
0.2 155.1,155.1 81,-81ZM249.5,439.3c-104.8,0 -189.9,-85 -189.9,-189.9s85,-189.9 189.9,-189.9S439.3,144.6 439.3,
249.5 354.3,439.3 249.5,439.3ZM157.3,133l7.7,-22.1a161.3,161.3 0,0 1,52.5 -20.5l-19.8,56.8A19.3,19.3 0,0 1,
173.1 158.9l-4,-1.4A19.3,19.3 0,0 1,157.3 133ZM177.4,215.6L135.3,288.4a19.3,19.3 0,0 1,-26.3 7l-3.7,-2.1a19.3,
19.3 0,0 1,-7 -26.3L140.3,194.2a19.3,19.3 0,0 1,26.3 -7l3.7,2.1A19.3,19.3 0,0 1,177.4 215.6ZM94.7,200.7A161.6,
161.6 0,0 1,114.1 159.9l9.1,9.1a19.3,19.3 0,0 1,0 27.2l-3,3A19.2,19.2 0,0 1,94.6 200.7ZM246.4,146.7A19.3,19.3 0,
0 1,257.3 121.7l55.5,-21.7a162.4,162.4 0,0 1,43.9 27.6A19.2,19.2 0,0 1,351.3 130.9l-78.3,30.6a19.3,19.3 0,0 1,
-24.9 -10.9ZM233,175.8 L299.7,227a19.3,19.3 0,0 1,3.5 27l-2.6,3.4a19.3,19.3 0,0 1,-27 3.5l-66.7,-51.2a19.3,19.3 0,
0 1,-3.5 -27l2.6,-3.4A19.3,19.3 0,0 1,233 175.8ZM316.6,367.3 L313.8,370.5a19.3,19.3 0,0 1,-27.1 1.9l-63.4,-55.3A19.3,
19.3 0,0 1,221.3 289.9l2.8,-3.2a19.3,19.3 0,0 1,27.2 -1.9l63.4,55.3A19.3,19.3 0,0 1,316.5 367.2ZM376.7,176.1 L380.7,
177.7a19.3,19.3 0,0 1,10.7 25l-31.3,78.1a19.3,19.3 0,0 1,-25 10.7l-4,-1.6A19.3,19.3 0,0 1,320.3 264.9l31.3,-78.1A19.3,
19.3 0,0 1,376.6 176.1ZM210,390.3a19.2,19.2 0,0 1,-4.8 15.4a161.4 161.4,0 0,1 -38.4,-16.5l-9.9,-76.8a19.3,19.3 0,0 1,
16.6 -21.5l4.3,-0.6A19.3,19.3 0,0 1,199.3 306.9ZM391.7,323.9L390.3,330.3a163.1,163.1 0,0 1,-56.5 57.9l16.1,-73.5a19.3,
19.3 0,0 1,22.9 -14.7l4.2,0.9A19.3,19.3 0,0 1,391.7 323.9Z"/>

尝试一下,看看效果是否更好。

解决方案

经过更多尝试(以及人们的帮助),我发现了问题所在。 问题出在填充规则上,就像其他人已经经历过的那样,但方式恰恰相反!

事实上,据我所知,VectorDrawable 使用非零填充规则,并且使用 evenodd 规则导出的 SVG 存在渲染问题。这就是为什么我一直使用非零规则。事实证明,使用 android:fillType="evenOdd" 可以解决我的问题。

我不知道为什么,在这一点上我不敢问。

在我的例子中,在我用三次贝塞尔曲线命令 (C) 替换所有椭圆弧命令 (A) 之前,没有任何帮助。任何圆弧都可以用一条或多条贝塞尔曲线表示。整个椭圆可以用4条贝塞尔曲线代替。

一旦您开始在 SVG 中编辑路径,Inkscape 往往会将圆弧转换为贝塞尔曲线,因此您可以使用 Inkscape 进行转换。看起来 Android 矢量渲染器在处理 A/a 命令时有严重的问题,不管它们是相对的还是绝对。因此,只需尝试转换 A/a => C/c.

请注意,仅更改命令字母是不够的,您需要适当设置控制点。

Native 不能显示圆弧,但是appCompat 可以。所以改为:

<ImageView
    android:src="@drawable/mydrawable"
/>

使用

app:srcCompat="@drawable/mydrawable"

就这么简单o_O。

(appxmlns:app="http://schemas.android.com/apk/res-auto")