layers: Update docs for default dbg msg callbacks

Change-Id: Ic1f192ea7c95762d7e53f091cc9f0ea55be96c04

1 files changed, 8 insertions, 6 deletions

diff --git a/layers/README.md b/layers/README.md
index e2cea90d..d3eecbf1 100644
--- a/layers/README.md
+++ b/layers/README.md
@@ -20,12 +20,14 @@ VkDevice, VkCommandBuffer, and VkQueue.
 vkXXXXGetProcAddr is used internally by the Layers and Loader to initialize dispatch tables.
 Layers can also be activated via the VK_INSTANCE_LAYERS environment variable.
 
-All validation layers work with the DEBUG_REPORT extension to provide the application or user with
-validation feedback. When a validation layer is enabled, it will look at the vk_layer_settings.txt
-file to determine its behavior. Such as outputing to a file, stdout or debug output (Windows). An
-application can also register callback functions via the DEBUG_REPORT extension to receive callbacks
-when the requested validation events happen. Application callbacks happen regardless of the
-settings in the vk_layer_settings.txt file.
+All validation layers work with the DEBUG_REPORT extension to provide validation feedback.
+When a validation layer is enabled, it will look for a vk_layer_settings.txt file to define
+its loggin behavior, which can include sending output to a file, stdout, or debug output (Windows).
+Applications can also register debug callback functions via the DEBUG_REPORT extension to receive
+callbacks when validation events occur. Application callbacks are independent of settings in a
+vk_layer_settings.txt file which will be carried out separately. If no vk_layer_settings.txt
+file is present and no application callbacks are registered, error messages will be output
+through default logging callbacks.
 
 ### Layer library example code