Archive for April, 2010

A PixelBender Rounded Rect Generator for After Effects

April 15, 2010 at 2:43 pm · Filed under After Effects, PixelBender

Why Rounded Rects? Because Steve Jobs says they are everywhere. And because a cursory search didn’t find anything for Pixel Bender. Use this plugin to generate a solid color rounded rect or sample footage to easily add rounded corners to your footage.

Tip of the Hat to David Van Brink for his Pixel Bender efforts and especially for making me think of the generative possibilities of Pixel Bender in addition to image processing. And to Greg Best whose Core Image Kernel is the basis for this.

<languageVersion : 1.0;>
 
kernel RoundedRect
<
    namespace : "";
    vendor : "Creative Workflow Hacks: Dale Bradshaw, http://creative-workflow-hacks.com";
    version : 1;
    description : "Generates a Rounded Rect given an Upper Left coordinate, a Bottom Right coordinate, a Corner radius, and a Color or Sampled Footage";
    displayname: "Rounded Rect";
>
{
    input image4 image;
    output pixel4 result;
 
    parameter float4 color
  <defaultValue: float4(1,1,1,1);
   aeDisplayName: "Rect Color";
   aeUIControl: "aeColor";>;
 
   parameter bool transfer<defaultValue: false;aeUIControl: "aeCheckbox";aeDisplayName: "Sample Footage";>;
   parameter float radius<defaultValue:25.0;minValue:0.0;maxValue:100.0;>;
   parameter float2 upperLeft<aePointRelativeDefaultValue: float2(0.01, 0.01);aeDisplayName: "Upper Left";aeUIControl: "aePoint";>;
   parameter float2 bottomRight<aePointRelativeDefaultValue: float2(.98,.98);aeDisplayName: "Bottom Right";aeUIControl: "aePoint";>;
 
   void
    evaluatePixel()
    {
 
        float2 p = outCoord();
        float dist = 0.0;
 
        dist += (p.x < upperLeft.x + radius) ? pow((upperLeft.x + radius) - p.x, 2.0) : 0.0;
        dist += (p.y < upperLeft.y + radius) ? pow((upperLeft.y + radius) - p.y, 2.0) : 0.0;
        dist += (p.x > bottomRight.x -radius)   ? pow((bottomRight.x -radius) - p.x, 2.0)   : 0.0;
        dist += (p.y > bottomRight.y - radius)  ? pow((bottomRight.y -radius) - p.y, 2.0)   : 0.0;
 
        dist = sqrt(dist);
        dist = clamp(radius - dist, 0.0, 1.0);
 
        if(transfer)
        result = sampleNearest(image,p) * dist;
        else
        result = color * dist;
 
    }
}

Download db_roundedRect.pbk Pixel Bender kernel

This Kernel is set up as After Effects plugin, but it should be relatively easy to setup for Flash. I’ll update it when I get a chance to check it out.

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