- rgtc1_block_internal(dst, stride, block, 0, 1);
+ rgtc1_block_internal(dst, stride, block, 0, 1, 3, 4);
+
+ return 8;
+}
+
+/**
+ * Decompress one block of a RGTC1 texture with unsigned components
+ * to Gray 8.
+ *
+ * @param dst output buffer.
+ * @param stride scanline in bytes.
+ * @param block block to decompress.
+ * @return how much texture data has been consumed.
+ */
+static int rgtc1u_gray_block(uint8_t *dst, ptrdiff_t stride, const uint8_t *block)
+{
+ rgtc1_block_internal(dst, stride, block, 0, 1, 0, 1);