[client] egl: added new super+N binding to increase image gain

This feture is to allow the use of the key combination <super>+N to
increase the brightness of the screen when using monitors with poor
backlighting. Can help in some games.

N = Night vision

VERSION

@@ -1 +1 @@
-a12-124-g5aef2422e0+1
+a12-124-gfd4cfc2ff3+1

client/renderers/EGL/desktop.c

@@ -28,6 +28,8 @@ Place, Suite 330, Boston, MA 02111-1307 USA
 #include <stdlib.h>
 #include <string.h>
 
+#include "interface/app.h"
+
 // these headers are auto generated by cmake
 #include "desktop.vert.h"
 #include "desktop_rgb.frag.h"
@@ -45,6 +47,7 @@ struct EGL_Desktop
 
   // uniforms
   GLint uDesktopPos;
+  GLint uNV, uNVGain;
 
   // internals
   enum EGL_PixelFormat pixFmt;
@@ -52,8 +55,16 @@ struct EGL_Desktop
   unsigned int         pitch;
   const uint8_t      * data;
   bool                 update;
+
+  // night vision
+  KeybindHandle kbNV;
+  bool  nv;
+  int   nvGain;
 };
 
+// forwards
+void egl_desktop_toggle_nv(SDL_Scancode key, void * opaque);
+
 bool egl_desktop_init(EGL_Desktop ** desktop)
 {
   *desktop = (EGL_Desktop *)malloc(sizeof(EGL_Desktop));
@@ -108,9 +119,19 @@ bool egl_desktop_init(EGL_Desktop ** desktop)
   egl_model_set_default((*desktop)->model);
   egl_model_set_texture((*desktop)->model, (*desktop)->texture);
 
+  (*desktop)->kbNV = app_register_keybind(SDL_SCANCODE_N, egl_desktop_toggle_nv, *desktop);
+
   return true;
 }
 
+
+void egl_desktop_toggle_nv(SDL_Scancode key, void * opaque)
+{
+  EGL_Desktop * desktop = (EGL_Desktop *)opaque;
+  if (++desktop->nvGain == 4)
+    desktop->nvGain = 0;
+}
+
 void egl_desktop_free(EGL_Desktop ** desktop)
 {
   if (!*desktop)
@@ -121,6 +142,8 @@ void egl_desktop_free(EGL_Desktop ** desktop)
   egl_shader_free (&(*desktop)->shader_yuv    );
   egl_model_free  (&(*desktop)->model         );
 
+  app_release_keybind(&(*desktop)->kbNV);
+
   free(*desktop);
   *desktop = NULL;
 }
@@ -172,7 +195,11 @@ bool egl_desktop_perform_update(EGL_Desktop * desktop, const bool sourceChanged)
   if (sourceChanged)
   {
     if (desktop->shader)
+    {
       desktop->uDesktopPos = egl_shader_get_uniform_location(desktop->shader, "position");
+      desktop->uNV         = egl_shader_get_uniform_location(desktop->shader, "nv"      );
+      desktop->uNVGain     = egl_shader_get_uniform_location(desktop->shader, "nvGain"  );
+    }
 
     if (!egl_texture_setup(
       desktop->texture,
@@ -208,5 +235,13 @@ void egl_desktop_render(EGL_Desktop * desktop, const float x, const float y, con
 
   egl_shader_use(desktop->shader);
   glUniform4f(desktop->uDesktopPos, x, y, scaleX, scaleY);
+  if (desktop->nvGain)
+  {
+    glUniform1i(desktop->uNV, 1);
+    glUniform1f(desktop->uNVGain, (float)(desktop->nvGain+1));
+  }
+  else
+    glUniform1i(desktop->uNV, 0);
+
   egl_model_render(desktop->model);
 }

client/renderers/EGL/shader/desktop_rgb.frag

@@ -4,8 +4,12 @@ in  highp vec2 uv;
 out highp vec4 color;
 
 uniform sampler2D sampler1;
+uniform int nv;
+uniform highp float nvGain;
 
 void main()
 {
   color = texture(sampler1, uv);
+  if (nv == 1)
+    color *= nvGain;
 }

client/renderers/EGL/shader/desktop_yuv.frag

@@ -3,6 +3,9 @@
 in  highp vec2 uv;
 out highp vec4 color;
 
+uniform int nv;
+uniform highp float nvGain;
+
 uniform sampler2D sampler1;
 uniform sampler2D sampler2;
 uniform sampler2D sampler3;
@@ -24,4 +27,6 @@ void main()
   );
   
   color = yuv * yuv_to_rgb;
+  if (nv == 1)
+    color *= nvGain;
 }