vulkan/overlay: make overlay size configurable

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>

src/vulkan/overlay-layer/overlay.cpp

@@ -484,10 +484,11 @@ static void destroy_command_buffer_data(struct command_buffer_data *data)
 static struct swapchain_data *new_swapchain_data(VkSwapchainKHR swapchain,
                                                  struct device_data *device_data)
 {
+   struct instance_data *instance_data = device_data->instance;
    struct swapchain_data *data = rzalloc(NULL, struct swapchain_data);
    data->device = device_data;
    data->swapchain = swapchain;
-   data->window_size = ImVec2(300, 300);
+   data->window_size = ImVec2(instance_data->params.width, instance_data->params.height);
    map_object((void *) data->swapchain, data);
    return data;
 }

src/vulkan/overlay-layer/overlay_params.c

@@ -59,6 +59,15 @@ parse_no_display(const char *str)
    return strtol(str, NULL, 0) != 0;
 }
 
+static unsigned
+parse_unsigned(const char *str)
+{
+   return strtol(str, NULL, 0);
+}
+
+#define parse_width(s) parse_unsigned(s)
+#define parse_height(s) parse_unsigned(s)
+
 static bool
 parse_help(const char *str)
 {
@@ -73,6 +82,8 @@ parse_help(const char *str)
    fprintf(stderr, "\tfps_sampling_period=number-of-milliseconds\n");
    fprintf(stderr, "\tno_display=0|1\n");
    fprintf(stderr, "\toutput_file=/path/to/output.txt\n");
+   fprintf(stderr, "\twidth=width-in-pixels\n");
+   fprintf(stderr, "\theight=height-in-pixels\n");
 
    return true;
 }
@@ -136,6 +147,7 @@ parse_overlay_env(struct overlay_params *params,
    params->enabled[OVERLAY_PARAM_ENABLED_fps] = true;
    params->enabled[OVERLAY_PARAM_ENABLED_frame_timing] = true;
    params->fps_sampling_period = 500000; /* 500ms */
+   params->width = params->height = 300;
 
    if (!env)
       return;

src/vulkan/overlay-layer/overlay_params.h

@@ -65,6 +65,8 @@ extern "C" {
    OVERLAY_PARAM_CUSTOM(fps_sampling_period)         \
    OVERLAY_PARAM_CUSTOM(output_file)                 \
    OVERLAY_PARAM_CUSTOM(position)                    \
+   OVERLAY_PARAM_CUSTOM(width)                       \
+   OVERLAY_PARAM_CUSTOM(height)                      \
    OVERLAY_PARAM_CUSTOM(no_display)                  \
    OVERLAY_PARAM_CUSTOM(help)
 
@@ -91,6 +93,8 @@ struct overlay_params {
    uint32_t fps_sampling_period; /* us */
    bool help;
    bool no_display;
+   unsigned width;
+   unsigned height;
 };
 
 const extern char *overlay_param_names[];