feat: add skin support.

Author: Trico-Everfire

include/studiomodelpp/structs/MDL.h

@@ -326,6 +326,7 @@ struct MDL {
 	//int materialOffset;
 	std::vector<Material> materials;
 
+    std::vector<std::vector<short>> skins;
 	//int materialDirCount;
 	//int materialDirOffset;
 	std::vector<std::string> materialDirectories;

src/studiomodelpp/structs/MDL.cpp

@@ -2,6 +2,7 @@
 
 #include <BufferStream.h>
 #include <sourcepp/detail/BufferUtils.h>
+#include <iostream>
 
 using namespace sourcepp;
 using namespace sourcepp::detail;
@@ -45,13 +46,13 @@ bool MDL::open(const std::byte* data, std::size_t size) {
 	int hitboxSetCount = stream.read<int>();
 	int hitboxSetOffset = stream.read<int>();
 
-	//int animDescCount = stream.read<int>();
-	//int animDescOffset = stream.read<int>();
+//	int animDescCount = stream.read<int>();
+//	int animDescOffset = stream.read<int>();
 	stream.skip<int>(2);
 
-	//int sequenceDescCount = stream.read<int>();
-	//int sequenceDescOffset = stream.read<int>();
-	stream.skip<int>(2);
+	int sequenceDescCount = stream.read<int>();
+	int sequenceDescOffset = stream.read<int>();
+//	stream.skip<int>(2);
 
 	stream.read(this->activityListVersion);
 	stream.read(this->eventsIndexed);
@@ -62,8 +63,10 @@ bool MDL::open(const std::byte* data, std::size_t size) {
 	int materialDirCount = stream.read<int>();
 	int materialDirOffset = stream.read<int>();
 
-	// todo: skins
-	stream.skip<int>(3);
+    int skinReferenceCount = stream.read<int>();
+    int skinReferenceFamilyCount = stream.read<int>();
+    int skinReferenceOffset = stream.read<int>();
+
 
 	int bodyPartCount = stream.read<int>();
 	int bodyPartOffset = stream.read<int>();
@@ -167,6 +170,28 @@ bool MDL::open(const std::byte* data, std::size_t size) {
 		readStringAtOffset(stream, materialDir, std::ios::beg, 0);
 	}
 
+    //The short is the skindex of a material in the this.materials vector.
+    //The skin family is the amount of textures per skin.
+    //As weird as the valve developer wiki makes it out.
+    //The two numbers:
+    //(skin0) -> (00 00)(material0) (02 00)(material2)
+    //(skin0) -> (01 00)(material1) (02 00)(material2)
+    //(skin0) -> (02 00)(material2) (02 00)(material2)
+    //Are two bytes grouped into a short.
+    stream.seek(skinReferenceOffset);
+    for (int i = 0; i < skinReferenceFamilyCount; i++)
+    {
+        std::vector<short> skinFamily;
+        for(int j = 0; j < skinReferenceCount; j++)
+        {
+            short skin;
+            stream.read<short>(skin);
+            skinFamily.push_back(skin);
+            std::cout << "material index " << j << " (material: " << materials[skin].name << ")" << " of skin" << i << std::endl;
+        }
+        this->skins.push_back(skinFamily);
+    }
+
 	for (int i = 0; i < bodyPartCount; i++) {
 		auto bodyPartPos = bodyPartOffset + i * (sizeof(int) * 4);
 		stream.seek(bodyPartPos);