From b63a90439982772a263e9da7d52fd824937bb811 Mon Sep 17 00:00:00 2001
From: hunterk <hunter_kaller@yahoo.com>
Date: Mon, 23 Jan 2017 16:34:10 -0600
Subject: [PATCH] add bevel shader

---
 retro/bevel.slangp        |  4 ++
 retro/shaders/bevel.slang | 86 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 90 insertions(+)
 create mode 100644 retro/bevel.slangp
 create mode 100644 retro/shaders/bevel.slang

diff --git a/retro/bevel.slangp b/retro/bevel.slangp
new file mode 100644
index 0000000..92f462c
--- /dev/null
+++ b/retro/bevel.slangp
@@ -0,0 +1,4 @@
+shaders = 1
+
+shader0 = shaders/bevel.slang
+filter_linear0 = false
\ No newline at end of file
diff --git a/retro/shaders/bevel.slang b/retro/shaders/bevel.slang
new file mode 100644
index 0000000..cb7a786
--- /dev/null
+++ b/retro/shaders/bevel.slang
@@ -0,0 +1,86 @@
+#version 450
+
+/*
+   Hyllian's Bevel Shader
+  
+   Copyright (C) 2011-2014 Hyllian/Jararaca - sergiogdb@gmail.com
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; either version 2
+   of the License, or (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+
+*/
+
+layout(push_constant) uniform Push
+{
+	vec4 SourceSize;
+	vec4 OriginalSize;
+	vec4 OutputSize;
+	uint FrameCount;
+	float BEVEL_LEVEL;
+} params;
+
+#pragma parameter BEVEL_LEVEL "Bevel Level" 0.2 0.0 0.5 0.01
+#define BEVEL_LEVEL params.BEVEL_LEVEL
+
+layout(std140, set = 0, binding = 0) uniform UBO
+{
+	mat4 MVP;
+} global;
+
+// Constants used with gamma correction.
+#define InputGamma             2.4
+#define OutputGamma            2.2
+
+#define GAMMA_IN(color)     pow(color, vec3(InputGamma, InputGamma, InputGamma))
+#define GAMMA_OUT(color)    pow(color, vec3(1.0 / OutputGamma, 1.0 / OutputGamma, 1.0 / OutputGamma))
+
+vec3 bevel(vec2 pos, vec3 color)
+{
+    vec3 weight;
+
+    float r = sqrt(dot(pos, vec2(1.0)));
+
+    vec3 delta = mix(vec3(BEVEL_LEVEL), vec3(1.0-BEVEL_LEVEL), color);
+
+    weight = delta*(1-r);
+
+    return color+weight;
+}
+
+#pragma stage vertex
+layout(location = 0) in vec4 Position;
+layout(location = 1) in vec2 TexCoord;
+layout(location = 0) out vec2 vTexCoord;
+
+void main()
+{
+   gl_Position = global.MVP * Position;
+   vTexCoord = TexCoord;
+}
+
+#pragma stage fragment
+layout(location = 0) in vec2 vTexCoord;
+layout(location = 0) out vec4 FragColor;
+layout(set = 0, binding = 2) uniform sampler2D Source;
+
+void main()
+{
+    vec2 position = fract(vTexCoord*params.SourceSize.xy);
+
+    vec3 color = GAMMA_IN(texture(Source, vTexCoord).rgb);
+
+    color = clamp(bevel(position, color), 0.0, 1.0);
+
+   FragColor = vec4(GAMMA_OUT(color), 1.0);
+}
\ No newline at end of file