From c9ed9108798207d01123d28fb2f027e4066f930a Mon Sep 17 00:00:00 2001
From: Brandon Wright <bearoso@gmail.com>
Date: Sat, 12 May 2018 17:36:45 -0500
Subject: [PATCH] Last pass filter.

---
 gtk/src/gtk_display_driver_opengl.cpp |  2 +-
 gtk/src/shaders/glsl.cpp              | 16 ++++++++++++----
 gtk/src/shaders/glsl.h                |  2 +-
 3 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/gtk/src/gtk_display_driver_opengl.cpp b/gtk/src/gtk_display_driver_opengl.cpp
index 6b8c78d0..30b8aea0 100644
--- a/gtk/src/gtk_display_driver_opengl.cpp
+++ b/gtk/src/gtk_display_driver_opengl.cpp
@@ -226,7 +226,7 @@ S9xOpenGLDisplayDriver::update (int width, int height, int yoffset)
 
     if (using_shaders && using_glsl_shaders)
     {
-        glsl_shader->render (texmap, width, height, w, h);
+        glsl_shader->render (texmap, width, height, w, h, x, allocation.height - y - h);
         glViewport (x, allocation.height - y - h, w, h);
     }
     else if (using_shaders && using_cg_shaders)
diff --git a/gtk/src/shaders/glsl.cpp b/gtk/src/shaders/glsl.cpp
index b824710b..95d2785a 100644
--- a/gtk/src/shaders/glsl.cpp
+++ b/gtk/src/shaders/glsl.cpp
@@ -152,7 +152,7 @@ bool GLSLShader::load_shader_file (char *filename)
         GLSLPass pass;
 
         snprintf(key, 256, "::filter_linear%u", i);
-        pass.filter = conf.Exists(key) ? conf.GetBool(key) ? GL_LINEAR : GL_NEAREST : GLSL_UNDEFINED;
+        pass.filter = conf.Exists(key) ? (conf.GetBool(key) ? GL_LINEAR : GL_NEAREST) : GLSL_UNDEFINED;
 
         sprintf(key, "::scale_type%u", i);
         const char* scaleType = conf.GetString(key, "");
@@ -543,7 +543,7 @@ bool GLSLShader::load_shader (char *filename)
     return true;
 }
 
-void GLSLShader::render(GLuint &orig, int width, int height, int viewport_width, int viewport_height)
+void GLSLShader::render(GLuint &orig, int width, int height, int viewport_width, int viewport_height, int viewport_x, int viewport_y)
 {
     frame_count++;
 
@@ -557,6 +557,8 @@ void GLSLShader::render(GLuint &orig, int width, int height, int viewport_width,
    */
     for (unsigned int i = 1; i < pass.size(); i++)
     {
+        bool lastpass = (i == pass.size() - 1);
+
         switch (pass[i].scale_type_x)
         {
         case GLSL_ABSOLUTE:
@@ -631,14 +633,20 @@ void GLSLShader::render(GLuint &orig, int width, int height, int viewport_width,
                                0);
 
         // set up input texture (output of previous pass) and apply filter settings
+
+        GLuint filter = (pass[i].filter == GLSL_UNDEFINED) ?
+                         (lastpass ?
+                          (gui_config->bilinear_filter ? GL_LINEAR : GL_NEAREST) : GL_NEAREST
+                              ) : pass[i].filter;
+
         glBindTexture(GL_TEXTURE_2D, pass[i - 1].texture);
         glPixelStorei(GL_UNPACK_ROW_LENGTH, (GLint) pass[i - 1].width);
         glTexParameteri(GL_TEXTURE_2D,
                         GL_TEXTURE_MAG_FILTER,
-                        pass[i].filter == GLSL_UNDEFINED ? GL_NEAREST : pass[i].filter);
+                        filter);
         glTexParameteri(GL_TEXTURE_2D,
                         GL_TEXTURE_MIN_FILTER,
-                        pass[i].filter == GLSL_UNDEFINED ? GL_NEAREST : pass[i].filter);
+                        filter);
 
         glTexCoordPointer(2, GL_FLOAT, 0, tex_coords);
 
diff --git a/gtk/src/shaders/glsl.h b/gtk/src/shaders/glsl.h
index a5927f65..1c04f780 100644
--- a/gtk/src/shaders/glsl.h
+++ b/gtk/src/shaders/glsl.h
@@ -106,7 +106,7 @@ typedef struct
 {
     bool load_shader (char *filename);
     bool load_shader_file (char *filename);
-    void render (GLuint &orig, int width, int height, int viewport_width, int viewport_height);
+    void render (GLuint &orig, int width, int height, int viewport_width, int viewport_height, int viewport_x, int viewport_y);
     void set_shader_vars (int pass);
     void clear_shader_vars (void);
     void strip_parameter_pragmas(char *buffer);