From 96886e21d57f26260cb54fccdcea4dcbb5c9c1f2 Mon Sep 17 00:00:00 2001
From: Andri Yngvason <andri@yngvason.is>
Date: Sun, 5 Sep 2021 00:20:05 +0000
Subject: [PATCH] Add a API function to get the pixel size of nvnc_fb

---
 include/neatvnc.h |  1 +
 include/pixels.h  |  2 ++
 src/fb.c          |  7 +++++++
 src/pixels.c      | 30 ++++++++++++++++++++++++++++--
 4 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/include/neatvnc.h b/include/neatvnc.h
index 6b3f9f7..d10e5c9 100644
--- a/include/neatvnc.h
+++ b/include/neatvnc.h
@@ -97,6 +97,7 @@ uint16_t nvnc_fb_get_width(const struct nvnc_fb* fb);
 uint16_t nvnc_fb_get_height(const struct nvnc_fb* fb);
 uint32_t nvnc_fb_get_fourcc_format(const struct nvnc_fb* fb);
 int32_t nvnc_fb_get_stride(const struct nvnc_fb* fb);
+int nvnc_fb_get_pixel_size(const struct nvnc_fb* fb);
 
 struct nvnc_fb_pool* nvnc_fb_pool_new(uint16_t width, uint16_t height,
 				      uint32_t fourcc_format, uint16_t stride);
diff --git a/include/pixels.h b/include/pixels.h
index 5b50989..3ebd1d9 100644
--- a/include/pixels.h
+++ b/include/pixels.h
@@ -29,3 +29,5 @@ void pixel32_to_cpixel(uint8_t* restrict dst,
 
 int rfb_pixfmt_from_fourcc(struct rfb_pixel_format *dst, uint32_t src);
 uint32_t rfb_pixfmt_to_fourcc(const struct rfb_pixel_format* fmt);
+
+int pixel_size_from_fourcc(uint32_t fourcc);
diff --git a/src/fb.c b/src/fb.c
index 32ba580..789d6b9 100644
--- a/src/fb.c
+++ b/src/fb.c
@@ -15,6 +15,7 @@
  */
 
 #include "fb.h"
+#include "pixels.h"
 #include "neatvnc.h"
 
 #include <stdlib.h>
@@ -99,6 +100,12 @@ int32_t nvnc_fb_get_stride(const struct nvnc_fb* fb)
 	return fb->stride;
 }
 
+EXPORT
+int nvnc_fb_get_pixel_size(const struct nvnc_fb* fb)
+{
+	return pixel_size_from_fourcc(fb->fourcc_format);
+}
+
 static void nvnc__fb_free(struct nvnc_fb* fb)
 {
 	nvnc_cleanup_fn cleanup = fb->common.cleanup_fn;
diff --git a/src/pixels.c b/src/pixels.c
index 5f00bd1..9b25909 100644
--- a/src/pixels.c
+++ b/src/pixels.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019 - 2020 Andri Yngvason
+ * Copyright (c) 2019 - 2021 Andri Yngvason
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -220,4 +220,30 @@ bpp_16:
 	dst->true_colour_flag = 1;
 
 	return 0;
-};
+}
+
+int pixel_size_from_fourcc(uint32_t fourcc)
+{
+	switch (fourcc & ~DRM_FORMAT_BIG_ENDIAN) {
+	case DRM_FORMAT_RGBA8888:
+	case DRM_FORMAT_RGBX8888:
+	case DRM_FORMAT_BGRA8888:
+	case DRM_FORMAT_BGRX8888:
+	case DRM_FORMAT_ARGB8888:
+	case DRM_FORMAT_XRGB8888:
+	case DRM_FORMAT_ABGR8888:
+	case DRM_FORMAT_XBGR8888:
+		return 4;
+	case DRM_FORMAT_RGBA4444:
+	case DRM_FORMAT_RGBX4444:
+	case DRM_FORMAT_BGRA4444:
+	case DRM_FORMAT_BGRX4444:
+	case DRM_FORMAT_ARGB4444:
+	case DRM_FORMAT_XRGB4444:
+	case DRM_FORMAT_ABGR4444:
+	case DRM_FORMAT_XBGR4444:
+		return 2;
+	}
+
+	return 0;
+}