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@NedMakesGames
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// MIT License
// Copyright (c) 2020 NedMakesGames
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files(the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and / or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions :
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
#ifndef SOBELOUTLINES_INCLUDED
#define SOBELOUTLINES_INCLUDED
// The sobel effect runs by sampling the texture around a point to see
// if there are any large changes. Each sample is multiplied by a convolution
// matrix weight for the x and y components seperately. Each value is then
// added together, and the final sobel value is the length of the resulting float2.
// Higher values mean the algorithm detected more of an edge
// These are points to sample relative to the starting point
static float2 sobelSamplePoints[9] = {
float2(-1, 1), float2(0, 1), float2(1, 1),
float2(-1, 0), float2(0, 0), float2(1, 0),
float2(-1, -1), float2(0, -1), float2(1, -1),
};
// Weights for the x component
static float sobelXMatrix[9] = {
1, 0, -1,
2, 0, -2,
1, 0, -1
};
// Weights for the y component
static float sobelYMatrix[9] = {
1, 2, 1,
0, 0, 0,
-1, -2, -1
};
// This function runs the sobel algorithm over the depth texture
void DepthSobel_float(float2 UV, float Thickness, out float Out) {
float2 sobel = 0;
// We can unroll this loop to make it more efficient
// The compiler is also smart enough to remove the i=4 iteration, which is always zero
[unroll] for (int i = 0; i < 9; i++) {
float depth = SHADERGRAPH_SAMPLE_SCENE_DEPTH(UV + sobelSamplePoints[i] * Thickness);
sobel += depth * float2(sobelXMatrix[i], sobelYMatrix[i]);
}
// Get the final sobel value
Out = length(sobel);
}
// This function runs the sobel algorithm over the opaque texture
void ColorSobel_float(float2 UV, float Thickness, out float Out) {
// We have to run the sobel algorithm over the RGB channels separately
float2 sobelR = 0;
float2 sobelG = 0;
float2 sobelB = 0;
// We can unroll this loop to make it more efficient
// The compiler is also smart enough to remove the i=4 iteration, which is always zero
[unroll] for (int i = 0; i < 9; i++) {
// Sample the scene color texture
float3 rgb = SHADERGRAPH_SAMPLE_SCENE_COLOR(UV + sobelSamplePoints[i] * Thickness);
// Create the kernel for this iteration
float2 kernel = float2(sobelXMatrix[i], sobelYMatrix[i]);
// Accumulate samples for each color
sobelR += rgb.r * kernel;
sobelG += rgb.g * kernel;
sobelB += rgb.b * kernel;
}
// Get the final sobel value
// Combine the RGB values by taking the one with the largest sobel value
Out = max(length(sobelR), max(length(sobelG), length(sobelB)));
// This is an alternate way to combine the three sobel values by taking the average
// See which one you like better
//Out = (length(sobelR) + length(sobelG) + length(sobelB)) / 3.0;
}
#endif
@Asues
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Asues commented Jan 23, 2021

I belive that u have made a littel mistake,the last component of line 35 should be float2(1,0) not float2(1,1) 😄
Thanks for the YouTube Video

@NedMakesGames
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Oh thanks! I'll fix that

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