slang-shaders/blurs/vertex-shader-blur-resize-horizontal.h

65 lines
2.8 KiB
C

#ifndef VERTEX_SHADER_BLUR_RESIZE_HORIZONTAL_H
#define VERTEX_SHADER_BLUR_RESIZE_HORIZONTAL_H
///////////////////////////////// MIT LICENSE ////////////////////////////////
// Copyright (C) 2014 TroggleMonkey
//
// 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.
///////////////////////////// SETTINGS MANAGEMENT ////////////////////////////
// PASS SETTINGS:
// Pass settings should be set by the shader file that #includes this one.
////////////////////////////////// INCLUDES //////////////////////////////////
//#include "../include/gamma-management.h"
//#include "../include/blur-functions.h"
#pragma stage vertex
layout(location = 0) in vec4 Position;
layout(location = 1) in vec2 TexCoord;
layout(location = 0) out vec2 tex_uv;
layout(location = 1) out vec2 blur_dxdy;
void main()
{
gl_Position = global.MVP * Position;
tex_uv = TexCoord;
// Get the uv sample distance between output pixels. Blurs are not generic
// Gaussian resizers, and correct blurs require:
// 1.) OutputSize.xy == SourceSize.xy * 2^m, where m is an integer <= 0.
// 2.) mipmap_inputN = "true" for this pass in .cgp preset if m != 0
// 3.) filter_linearN = "true" except for 1x scale nearest neighbor blurs
// Arbitrary upsizing will be acceptable if filter_linearN = "true", and
// arbitrary downsizing will be acceptable if mipmap_inputN = "true" too.
// Only the "resize" blurs can manage this though, and they still aren't
// proper Gaussian resizers (because they sample between texels and always
// blur after resizing, not during).
const vec2 dxdy_scale = params.SourceSize.xy * params.OutputSize.zw;
const vec2 dxdy = dxdy_scale * params.SourceSize.zw;
// This blur is horizontal-only, so zero out the vertical offset:
blur_dxdy = vec2(dxdy.x, 0.0);
}
#endif // VERTEX_SHADER_BLUR_RESIZE_HORIZONTAL_H