[client] renderer: add ability to toggle the FPS display

Before, if you want to see the FPS, you need to close the client and
restart it with the -k switch to see the FPS. This is annoying.

This PR introduces a new keybind, ScrollLock+D, which, when pressed,
toggles the display of the FPS.

This is implemented for both EGL and OpenGL backends.

client/renderers/EGL/egl.c

@@ -499,6 +499,12 @@ void egl_on_help(void * opaque, const char * message)
   egl_help_set_text(this->help, message);
 }
 
+void egl_on_show_fps(void * opaque, bool showFPS)
+{
+  struct Inst * this = (struct Inst *)opaque;
+  egl_fps_set_display(this->fps, showFPS);
+}
+
 bool egl_render_startup(void * opaque)
 {
   struct Inst * this = (struct Inst *)opaque;
@@ -738,9 +744,6 @@ bool egl_render(void * opaque, LG_RendererRotate rotate)
 void egl_update_fps(void * opaque, const float avgUPS, const float avgFPS)
 {
   struct Inst * this = (struct Inst *)opaque;
-  if (!this->params.showFPS)
-    return;
-
   egl_fps_update(this->fps, avgUPS, avgFPS);
 }
 
@@ -760,6 +763,7 @@ struct LG_Renderer LGR_EGL =
   .on_frame        = egl_on_frame,
   .on_alert        = egl_on_alert,
   .on_help         = egl_on_help,
+  .on_show_fps     = egl_on_show_fps,
   .render_startup  = egl_render_startup,
   .render          = egl_render,
   .update_fps      = egl_update_fps

client/renderers/EGL/fps.c

@@ -42,6 +42,7 @@ struct EGL_FPS
   EGL_Shader  * shaderBG;
   EGL_Model   * model;
 
+  bool  display;
   bool  ready;
   int   iwidth, iheight;
   float width, height;
@@ -132,8 +133,16 @@ void egl_fps_free(EGL_FPS ** fps)
   *fps = NULL;
 }
 
+void egl_fps_set_display(EGL_FPS * fps, bool display)
+{
+  fps->display = display;
+}
+
 void egl_fps_update(EGL_FPS * fps, const float avgFPS, const float renderFPS)
 {
+  if (!fps->display)
+    return;
+
   char str[128];
   snprintf(str, sizeof(str), "UPS: %8.4f, FPS: %8.4f", avgFPS, renderFPS);
 
@@ -174,7 +183,7 @@ void egl_fps_update(EGL_FPS * fps, const float avgFPS, const float renderFPS)
 
 void egl_fps_render(EGL_FPS * fps, const float scaleX, const float scaleY)
 {
-  if (!fps->ready)
+  if (!fps->display || !fps->ready)
     return;
 
   glEnable(GL_BLEND);

client/renderers/EGL/fps.h

@@ -28,5 +28,6 @@ typedef struct EGL_FPS EGL_FPS;
 bool egl_fps_init(EGL_FPS ** fps, const LG_Font * font, LG_FontObj fontObj);
 void egl_fps_free(EGL_FPS ** fps);
 
+void egl_fps_set_display(EGL_FPS * fps, bool display);
 void egl_fps_update(EGL_FPS * fps, const float avgUPS, const float avgFPS);
 void egl_fps_render(EGL_FPS * fps, const float scaleX, const float scaleY);

client/renderers/OpenGL/opengl.c

@@ -148,6 +148,7 @@ struct Inst
   uint64_t          waitFadeTime;
   bool              waitDone;
 
+  bool              showFPS;
   bool              fpsTexture;
   SDL_Rect          fpsRect;
 
@@ -466,6 +467,12 @@ void opengl_on_help(void * opaque, const char * message)
   // TODO: Implement this.
 }
 
+void opengl_on_show_fps(void * opaque, bool showFPS)
+{
+  struct Inst * this = (struct Inst *)opaque;
+  this->showFPS = showFPS;
+}
+
 void bitmap_to_texture(LG_FontBitmap * bitmap, GLuint texture)
 {
   glBindTexture(GL_TEXTURE_2D       , texture      );
@@ -583,7 +590,7 @@ bool opengl_render(void * opaque, LG_RendererRotate rotate)
       render_wait(this);
   }
 
-  if (this->fpsTexture)
+  if (this->showFPS && this->fpsTexture)
     glCallList(this->fpsList);
 
   struct Alert * alert;
@@ -668,7 +675,7 @@ bool opengl_render(void * opaque, LG_RendererRotate rotate)
 void opengl_update_fps(void * opaque, const float avgUPS, const float avgFPS)
 {
   struct Inst * this = (struct Inst *)opaque;
-  if (!this->params.showFPS)
+  if (!this->showFPS)
     return;
 
   char str[128];
@@ -829,6 +836,7 @@ const LG_Renderer LGR_OpenGL =
   .on_frame        = opengl_on_frame,
   .on_alert        = opengl_on_alert,
   .on_help         = opengl_on_help,
+  .on_show_fps     = opengl_on_show_fps,
   .render_startup  = opengl_render_startup,
   .render          = opengl_render,
   .update_fps      = opengl_update_fps