60 lines
No EOL
2.1 KiB
HLSL
60 lines
No EOL
2.1 KiB
HLSL
#include "../space/rotate.hlsl"
|
|
#include "../space/braketing.hlsl"
|
|
|
|
#include "../sampler.hlsl"
|
|
|
|
/*
|
|
contributors: Huw Bowles
|
|
description: |
|
|
'Bracketing' technique maps a texture to a plane using any arbitrary 2D vector field to give orientatio. From https://www.shadertoy.com/view/NddcDr
|
|
use: sampleBracketing(<SAMPLER_TYPE> texture, <float2> st, <float2> direction [, <float> scale] )
|
|
options:
|
|
- BRACKETING_ANGLE_DELTA:
|
|
- SAMPLER_FNC(TEX, UV): optional depending the target version of GLSL (texture2D(...) or texture(...))
|
|
- SAMPLEBRACKETING_TYPE:
|
|
- SAMPLEBRACKETING_SAMPLER_FNC(UV):
|
|
- SAMPLEBRACKETING_REPLACE_DIVERGENCE:
|
|
license: MIT license (MIT) Copyright Huw Bowles May 2022
|
|
*/
|
|
|
|
#ifndef SAMPLEBRACKETING_TYPE
|
|
#define SAMPLEBRACKETING_TYPE float4
|
|
#endif
|
|
|
|
#ifndef SAMPLEBRACKETING_SAMPLER_FNC
|
|
#define SAMPLEBRACKETING_SAMPLER_FNC(UV) SAMPLER_FNC(tex, UV)
|
|
#endif
|
|
|
|
#ifndef FNC_SAMPLEBRACKETING
|
|
#define FNC_SAMPLEBRACKETING
|
|
|
|
SAMPLEBRACKETING_TYPE sampleBracketing(SAMPLER_TYPE tex, float2 st, float2 dir, float scale) {
|
|
float2 vAxis0 = float2(0.0, 0.0);
|
|
float2 vAxis1 = float2(0.0, 0.0);
|
|
float blendAlpha = 0.0;
|
|
|
|
bracketing(dir, vAxis0, vAxis1, blendAlpha);
|
|
|
|
// Compute the function for the two canonical directions
|
|
float2 uv0 = scale * rotate(st, vAxis0);
|
|
float2 uv1 = scale * rotate(st, vAxis1);
|
|
|
|
// Now sample function/texture
|
|
SAMPLEBRACKETING_TYPE sample0 = SAMPLEBRACKETING_SAMPLER_FNC(uv0);
|
|
SAMPLEBRACKETING_TYPE sample1 = SAMPLEBRACKETING_SAMPLER_FNC(uv1);
|
|
|
|
// Blend to get final result, based on how close the vector was to the first snapped angle
|
|
SAMPLEBRACKETING_TYPE result = lerp( sample0, sample1, blendAlpha);
|
|
|
|
#ifdef SAMPLEBRACKETING_REPLACE_DIVERGENCE
|
|
float strength = smoothstep(0.0, 0.2, dot(dir, dir)*6.0);
|
|
result = lerp( SAMPLEBRACKETING_SAMPLER_FNC(scale * rotate(st, -float2(cos(0.5),sin(0.5)))),
|
|
result,
|
|
strength);
|
|
#endif
|
|
|
|
return result;
|
|
}
|
|
|
|
SAMPLEBRACKETING_TYPE sampleBracketing(SAMPLER_TYPE tex, float2 st, float2 dir) { return sampleBracketing(tex, st, dir, 1.0); }
|
|
#endif |