Clarification

1 files changed, 9 insertions, 3 deletions

diff --git a/main.c b/main.c
index 4a32cd0..4572828 100755
--- a/main.c
+++ b/main.c
@@ -1315,6 +1315,11 @@ int rvkConfigureSurface(struct RenderVulkan *vk)
 
 static int rvkCreateRawSwapchain(struct RenderVulkan *vk, uint32_t width, uint32_t height)
 {
+	/* We must retrieve the surface capabilities every time we make a new
+	 * swapchain because it can change every frame. For example, the
+	 * minimum and maximum extents can change per-frame as the user drag-
+	 * resizes the window.
+	 */
 	VkSurfaceCapabilitiesKHR surfaceCapabilities;
 	VkResult result;
 	if ((result = vk->api->vkGetPhysicalDeviceSurfaceCapabilitiesKHR(
@@ -1337,9 +1342,10 @@ static int rvkCreateRawSwapchain(struct RenderVulkan *vk, uint32_t width, uint32
 	 * Nonetheless, clamping the returned window size to the minimum and
 	 * maximum surface capabilities seems to fix the problem completely.
 	 *
-	 * Furthermore, it may be possible that we don't even need to query the
-	 * window system for its size at all, and could possibly simply use the
-	 * `currentExtent` of the `VkSurfaceCapabilitiesKHR`.
+	 * The `currentExtent` may hold a special value `UINT32_MAX` to mean
+	 * that the extent will be chosen by the swapchain, instead of the
+	 * usual other way around. This is why we pass our own width and height
+	 * instead of just querying the `currentExtent`.
 	 */
 	width = CLAMP(width, surfaceCapabilities.minImageExtent.width, surfaceCapabilities.maxImageExtent.width);
 	height = CLAMP(height, surfaceCapabilities.minImageExtent.height, surfaceCapabilities.maxImageExtent.height);