Merge pull request #65717 from Ithamar/feat-tga-16bits

Add 16-bits TGA support

modules/tga/image_loader_tga.cpp

@@ -100,7 +100,7 @@ Error ImageLoaderTGA::convert_to_image(Ref<Image> p_image, const uint8_t *p_buff
 	uint32_t width = p_header.image_width;
 	uint32_t height = p_header.image_height;
 	tga_origin_e origin = static_cast<tga_origin_e>((p_header.image_descriptor & TGA_ORIGIN_MASK) >> TGA_ORIGIN_SHIFT);
-
+	uint8_t alpha_bits = p_header.image_descriptor & TGA_IMAGE_DESCRIPTOR_ALPHA_MASK;
 	uint32_t x_start;
 	int32_t x_step;
 	uint32_t x_end;
@@ -184,6 +184,27 @@ Error ImageLoaderTGA::convert_to_image(Ref<Image> p_image, const uint8_t *p_buff
 				y += y_step;
 			}
 		}
+	} else if (p_header.pixel_depth == 16) {
+		while (y != y_end) {
+			while (x != x_end) {
+				if (i + 1 >= p_input_size) {
+					return ERR_PARSE_ERROR;
+				}
+
+				// Always stored as RGBA5551
+				uint8_t r = (p_buffer[i + 1] & 0x7c) << 1;
+				uint8_t g = ((p_buffer[i + 1] & 0x03) << 6) | ((p_buffer[i + 0] & 0xe0) >> 2);
+				uint8_t b = (p_buffer[i + 0] & 0x1f) << 3;
+				uint8_t a = (p_buffer[i + 1] & 0x80) ? 0xff : 0;
+
+				TGA_PUT_PIXEL(r, g, b, alpha_bits ? a : 0xff);
+
+				x += x_step;
+				i += 2;
+			}
+			x = x_start;
+			y += y_step;
+		}
 	} else if (p_header.pixel_depth == 24) {
 		while (y != y_end) {
 			while (x != x_end) {
@@ -277,7 +298,7 @@ Error ImageLoaderTGA::load_image(Ref<Image> p_image, Ref<FileAccess> f, BitField
 		err = FAILED;
 	}
 
-	if (!(tga_header.pixel_depth == 8 || tga_header.pixel_depth == 24 || tga_header.pixel_depth == 32)) {
+	if (!(tga_header.pixel_depth == 8 || tga_header.pixel_depth == 16 || tga_header.pixel_depth == 24 || tga_header.pixel_depth == 32)) {
 		err = FAILED;
 	}
 

modules/tga/image_loader_tga.h

@@ -33,6 +33,8 @@
 
 #include "core/io/image_loader.h"
 
+#define TGA_IMAGE_DESCRIPTOR_ALPHA_MASK 0xf
+
 class ImageLoaderTGA : public ImageFormatLoader {
 	enum tga_type_e {
 		TGA_TYPE_NO_DATA = 0,