Kawase blur proof-of-concept

buffer_N.cpp

void mainImage( out vec4 fragColor, in vec2 fragCoord )
{
    // 0.5 - 1.5 - 2.5 - 3.5
    KawaseSample(fragColor, fragCoord, 0.5);
}

common.cpp

                            // Header: Enable access to inputs from Common tab
                            // See https://www.shadertoy.com/view/ttf3R4
                                #if __LINE__<17          // Must be on line 3!
                                #define _ST_TAB_COMMON
                                #endif
                                #if __LINE__<25
                                #define _ST_TAB_SOUND
                                uniform vec3 iResolution; // Sound tab
                                uniform float iTime;  // never defines these
                                #endif
                                #ifdef _ST_TAB_COMMON
                                #undef _ST_TAB_SOUND
                                uniform float iTimeDelta;
                                uniform int iFrame;
                                uniform float iChannelTime[4];
                                uniform vec3 iChannelResolution[4];
                                uniform vec4 iMouse;
                                // iDate and iSampleRate: Alread have them.
                                uniform sampler2D iChannel0;
                                uniform sampler2D iChannel1; // Change type to
                                uniform sampler2D iChannel2; // samplerCube
                                uniform sampler2D iChannel3; // if Cube input
                                #endif
                            // End header

void KawaseSample( out vec4 fragColor, in vec2 fragCoord, in float Shift)
{
    vec2 uv = fragCoord/iResolution.xy;
    vec2 Resolution = iChannelResolution[0].xy;
    
    vec3 BlurColor = texture(iChannel0, uv + vec2(Shift, Shift) / Resolution).rgb;
    BlurColor += texture(iChannel0, uv + vec2(Shift, -Shift) / Resolution).rgb;
    BlurColor += texture(iChannel0, uv + vec2(-Shift, Shift) / Resolution).rgb;
    BlurColor += texture(iChannel0, uv + vec2(-Shift, -Shift) / Resolution).rgb;
    BlurColor /= 4.0;
    
    fragColor = vec4(BlurColor, 1.0);
}

image.cpp

const float CircleSize = 0.75;
const float SmoothPadding = 0.33;

void mainImage( out vec4 fragColor, in vec2 fragCoord )
{
    vec2 uv = fragCoord/iResolution.xy;

    // Clear color
    vec3 ClearColor = texture(iChannel1, uv).rgb;
    
    // Kawase bluer
    vec4 BlurColor = vec4(0);
    KawaseSample(BlurColor, fragCoord, 4.5);
    
    // Calculate clear vision circle
    float AspectRatio = iResolution.x / iResolution.y;
    vec2 VisionCenter = iMouse.xy/iResolution.xy;

    vec2 v = uv - VisionCenter;
    v.x = v.x * AspectRatio;

    float CirleRadius = CircleSize / 2.0;
    float SmoothRadius = CirleRadius * SmoothPadding;
    float CircleMask = smoothstep(CirleRadius, CirleRadius - SmoothRadius, length(v));
    BlurColor.rgb = mix(BlurColor.rgb, ClearColor.rgb, CircleMask);
    
    fragColor = vec4(BlurColor);
}

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