Unity組件：Twirl image effect 旋轉(zhuǎn)扭曲圖像效果特效

The Twirl image effect distorts the rendered image within a circular region. The pixels at the centre of the circle are rotated by a specified angle; the rotation for other pixels in the circle decreases with distance from the centre, diminishing to zero at the circle's edge.

旋轉(zhuǎn)扭曲圖像特效是指在一個(gè)圓形區(qū)域內(nèi)扭曲所渲染的圖像。在圓形區(qū)域中心的像素被旋轉(zhuǎn)一定的角度，而其他像素的旋轉(zhuǎn)程度隨著距中心距離的增大而減小，在圓形區(qū)域邊界減小到0。

Twirl is similar to another image effect called Vortex, although vortex distorts the image around a central circle rather than a single point.

旋轉(zhuǎn)扭曲圖像特效跟另一種叫做漩渦的圖像特效相似，只不過漩渦圖像特效是將圖像繞著一個(gè)中心圓旋轉(zhuǎn)，而非繞著單一的一個(gè)點(diǎn)。

As with the other image effects, this effect is only available in Unity Pro and you must have the Pro Standard Assets installed before it becomes available.

和其他圖像特效一樣，該特效只能在Unity Pro上進(jìn)行使用，并且在使用之前必須安裝Pro Standard Assets。

Twirl image effect applied to the scene

• Radius 半徑
  The radius of the ellipse where image distortion occurs, given in normalized screen coordinates (ie, a radius of 0.5 is half the size of the screen).
  在給定的歸一化屏幕坐標(biāo)中，圖像扭曲出現(xiàn)的位置上的橢圓半徑（ie，半徑為 0.5 是屏幕大小的一半）
• Angle 角度
  The angle of rotation at the centre point.
  中心點(diǎn)的旋轉(zhuǎn)角度
• Center 中心
  The point at the centre of the circle where distortion occurs.
  扭曲處的圓形區(qū)域中心點(diǎn)

Hardware support 硬件支持

This effect requires a graphics card with pixel shaders (2.0) or OpenGL ES 2.0. PC: NVIDIA cards since 2003 (GeForce FX), AMD cards since 2004 (Radeon 9500), Intel cards since 2005 (GMA 900); Mobile: OpenGL ES 2.0; Consoles: Xbox 360, PS3.

這個(gè)特效需要顯卡擁有像素著色器（2.0）或者OpenGL ES 2.0。臺(tái)式機(jī)：2003年以后的NVIDIA顯卡（GeForce FX），2004年以后的AMD顯卡（Radeon 9500），2005年以后的Intel卡（GMA 900）；移動(dòng)設(shè)備：OpenGL ES 2.0；控制臺(tái)： Xbox 360、 PS3。

All image effects automatically disable themselves when they can not run on end-users graphics card.

所有圖像特效如果無法在用戶顯卡上運(yùn)行時(shí)將會(huì)自動(dòng)被關(guān)閉。