LCD grid shader

src/platform/core/CMakeLists.txt

@@ -78,6 +78,7 @@ set(HEADERS
   src/device/shader/color_agb.glsl.hpp
   src/device/shader/common.glsl.hpp
   src/device/shader/lcd_ghosting.glsl.hpp
+  src/device/shader/lcd1x.glsl.hpp
   src/device/shader/output.glsl.hpp
   src/device/shader/sharp_bilinear.glsl.hpp
   src/device/shader/xbrz.glsl.hpp

src/platform/core/include/platform/config.hpp

@@ -29,7 +29,8 @@ struct PlatformConfig : Config {
       Nearest,
       Linear,
       Sharp,
-      xBRZ
+      xBRZ,
+      Lcd1x
     } filter = Filter::Linear;
 
     enum class Color {

src/platform/core/src/config.cpp

@@ -81,7 +81,8 @@ void PlatformConfig::Load(std::string const& path) {
         { "nearest", Video::Filter::Nearest },
         { "linear",  Video::Filter::Linear  },
         { "sharp",   Video::Filter::Sharp   },
-        { "xbrz",    Video::Filter::xBRZ    }
+        { "xbrz",    Video::Filter::xBRZ    },
+        { "lcd1x",   Video::Filter::Lcd1x   }
       };
 
       const std::map<std::string, Video::Color> color_corrections{
@@ -181,7 +182,8 @@ void PlatformConfig::Save(std::string const& path) {
     case Video::Filter::Nearest: filter = "nearest"; break;
     case Video::Filter::Linear:  filter = "linear"; break;
     case Video::Filter::Sharp:   filter = "sharp"; break;
-    case Video::Filter::xBRZ:    filter = "xbrz"; break; 
+    case Video::Filter::xBRZ:    filter = "xbrz"; break;
+    case Video::Filter::Lcd1x:   filter = "lcd1x"; break;
   }
 
   switch(this->video.color) {

src/platform/core/src/device/ogl_video_device.cpp

@@ -16,6 +16,7 @@
 #include "device/shader/color_higan.glsl.hpp"
 #include "device/shader/color_agb.glsl.hpp"
 #include "device/shader/lcd_ghosting.glsl.hpp"
+#include "device/shader/lcd1x.glsl.hpp"
 #include "device/shader/output.glsl.hpp"
 #include "device/shader/sharp_bilinear.glsl.hpp"
 #include "device/shader/xbrz.glsl.hpp"
@@ -186,7 +187,15 @@ void OGLVideoDevice::CreateShaderPrograms() {
     // Sharp bilinear.
     case Video::Filter::Sharp: {
       auto [success, program] = CompileProgram(sharp_bilinear_vert, sharp_bilinear_frag);
-      if (success) {
+      if(success) {
+        shader_passes.push_back({program});
+      }
+      break;
+    }
+    // Lcd1x filter
+    case Video::Filter::Lcd1x: {
+      auto [success, program] = CompileProgram(lcd1x_vert, lcd1x_frag);
+      if(success) {
         shader_passes.push_back({program});
       }
       break;

src/platform/core/src/device/shader/lcd1x.glsl.hpp

@@ -0,0 +1,60 @@
+/*
+ * lcd1x - Simple LCD 'scanline' shader, based on lcd3x
+ *
+ * Original code by Gigaherz, released into the public domain
+ *
+ * Ported to NanoBoyAdvance by Destiny
+ *
+ * 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.
+ *
+ * lcd1x differs from lcd3x in the following manner:
+ *
+ * > Omits LCD-style colour separation
+ *
+ * > Has 'correctly' aligned scanlines
+ */
+
+#pragma once
+
+constexpr auto lcd1x_vert = R"(
+  #version 330 core
+
+  layout(location = 0) in vec2 position;
+  layout(location = 1) in vec2 uv;
+
+  out vec2 v_uv;
+
+  void main() {
+    v_uv = vec2(uv.x, 1.0 - uv.y) * 1.0001;
+    gl_Position = vec4(position, 0.0, 1.0);
+  }
+)";
+
+constexpr auto lcd1x_frag = R"(
+  #version 330 core
+
+  #define BRIGHTEN_SCANLINES 16.0
+  #define BRIGHTEN_LCD 24.0
+  #define PI 3.141592653589793
+  #define INPUT_SIZE vec2(240,160)
+
+
+  layout(location = 0) out vec4 frag_color;
+
+  in vec2 v_uv;
+
+  uniform sampler2D u_input_map;
+
+  void main() {
+    vec2 angle = 2.0 * PI * ((v_uv.xy * INPUT_SIZE.xy) - 0.25);
+    float yfactor = (BRIGHTEN_SCANLINES + sin(angle.y)) / (BRIGHTEN_SCANLINES + 1.0);
+    float xfactor = (BRIGHTEN_LCD + sin(angle.x)) / (BRIGHTEN_LCD + 1.0);
+    vec3 colour = texture(u_input_map, v_uv).rgb;
+    colour.rgb = yfactor * xfactor * colour.rgb;
+
+    frag_color = vec4(colour.rgb, 1.0);
+  }
+)";

src/platform/qt/src/widget/main_window.cpp

@@ -177,7 +177,8 @@ void MainWindow::CreateVideoMenu(QMenu* parent) {
     { "Nearest", nba::PlatformConfig::Video::Filter::Nearest },
     { "Linear",  nba::PlatformConfig::Video::Filter::Linear  },
     { "Sharp",   nba::PlatformConfig::Video::Filter::Sharp   },
-    { "xBRZ",    nba::PlatformConfig::Video::Filter::xBRZ    }
+    { "xBRZ",    nba::PlatformConfig::Video::Filter::xBRZ    },
+    { "Lcd1x",   nba::PlatformConfig::Video::Filter::Lcd1x   }
   }, &config->video.filter, false, reload_config);
 
   CreateSelectionOption(menu->addMenu(tr("Color correction")), {