presets param: inherit

This option is only for presets. It inherits the default preset.
This allows you to modify an existing preset without having to rewrite it

src/overlay_params.cpp

@@ -967,6 +967,7 @@ bool parse_preset_config(int preset, struct overlay_params *params){
    char preset_string[20];
    snprintf(preset_string, sizeof(preset_string), "[preset %d]\n", preset);
    bool found_preset = false;
+
    if (preset_file == NULL)
       return false;
 
@@ -980,6 +981,14 @@ bool parse_preset_config(int preset, struct overlay_params *params){
          if(strcmp(line, "preset") == 0 || line[0] == '\n' || line[0] == '\0')
             break;
 
+         printf("line: %s\n", line);
+         std::string s;
+         s = line;
+         trim(s);
+
+         if (strcmp(s.c_str(), "inherit") == 0)
+            presets(preset, params, true);
+
          parseConfigLine(line, params->options);
       }
    }
@@ -993,9 +1002,10 @@ void add_to_options(struct overlay_params *params, std::string option, std::stri
    params->options[option] = value;
 }
 
-void presets(int preset, struct overlay_params *params) {
-   if (parse_preset_config(preset, params))
-      return;
+int i = 0;
+void presets(int preset, struct overlay_params *params, bool inherit) {
+   if (!inherit && parse_preset_config(preset, params))
+         return;
 
    switch(preset) {
       case 0:

src/overlay_params.h

@@ -104,6 +104,7 @@ typedef unsigned long KeySym;
    OVERLAY_PARAM_BOOL(temp_fahrenheit)               \
    OVERLAY_PARAM_BOOL(dynamic_frame_timing)          \
    OVERLAY_PARAM_BOOL(duration)                      \
+   OVERLAY_PARAM_BOOL(inherit)                       \
    OVERLAY_PARAM_CUSTOM(fps_sampling_period)         \
    OVERLAY_PARAM_CUSTOM(output_folder)               \
    OVERLAY_PARAM_CUSTOM(output_file)                 \
@@ -310,7 +311,7 @@ const extern char *overlay_param_names[];
 
 void parse_overlay_config(struct overlay_params *params,
                        const char *env, bool ignore_preset);
-void presets(int preset, struct overlay_params *params);
+void presets(int preset, struct overlay_params *params, bool inherit=false);
 bool parse_preset_config(int preset, struct overlay_params *params);
 void add_to_options(struct overlay_params *params, std::string option, std::string value);