diff --git a/.gitignore b/.gitignore
index 4b16b4b..96ea458 100644
--- a/.gitignore
+++ b/.gitignore
@@ -48,6 +48,7 @@ prodg*
 
 ## Linux
 *.swp
+*.d
 
 ## WSL
 *:Zone.Identifier
diff --git a/configure.py b/configure.py
index 46f27ef..73cff53 100644
--- a/configure.py
+++ b/configure.py
@@ -217,7 +217,7 @@ def do_clean(version: str, build_dir: Path) -> None:
 # Flags for C SDK libraries (no -lang=c++ override)
 cflags_c = [
     "-lang=c",
-    "-O3",
+    "-O3,p",
     "-i include",
     f"-DBUILD_VERSION={version_num}",
 ]
diff --git a/include/usr/local/sce/ee/gcc/ee/lib/libc/memset.h b/include/usr/local/sce/ee/gcc/ee/lib/libc/memset.h
index e69de29..4aabb7b 100644
--- a/include/usr/local/sce/ee/gcc/ee/lib/libc/memset.h
+++ b/include/usr/local/sce/ee/gcc/ee/lib/libc/memset.h
@@ -0,0 +1,6 @@
+#ifndef SCE_GCC_MEMSET_H
+#define SCE_GCC_MEMSET_H
+
+void * memset(void * ptr, int value, unsigned int num); //TODO: change "unsigned int num" to "size_t num"
+
+#endif
diff --git a/include/usr/local/sce/ee/lib/eestruct.h b/include/usr/local/sce/ee/lib/eestruct.h
new file mode 100644
index 0000000..3c27163
--- /dev/null
+++ b/include/usr/local/sce/ee/lib/eestruct.h
@@ -0,0 +1,11 @@
+#ifndef _EESTRUCT_H_
+#define _EESTRUCT_H_
+
+#define SCE_GIF_SET_TAG(nloop, eop, pre, prim, flg, nreg) \
+	((unsigned long)(nloop) | ((unsigned long)(eop)<<15) | ((unsigned long)(pre) << 46) | \
+	((unsigned long)(prim)<<47) | ((unsigned long)(flg)<<58) | ((unsigned long)(nreg)<<60))
+
+#define SCE_VIF1_SET_UNPACK(vuaddr, num, cmd, irq) ((unsigned int)(vuaddr) | ((unsigned int)(num) << 16) | ((unsigned int)(0x60 | (cmd)) << 24) | ((unsigned int)(irq) << 31))
+
+
+#endif /* _EESTRUCT_H_ */
diff --git a/include/usr/local/sega/px/src/pxtex2.h b/include/usr/local/sega/px/src/pxtex2.h
index 983536b..a5ad1bb 100644
--- a/include/usr/local/sega/px/src/pxtex2.h
+++ b/include/usr/local/sega/px/src/pxtex2.h
@@ -1,3 +1,6 @@
+#ifndef PXTEX2_H
+#define PXTEX2_H
+
 extern unsigned int pxgPath3TransAddr; // size: 0x4, address: 0x6D1F38
 extern unsigned int pxgPath3TransInvokeCount; // size: 0x4, address: 0x6D1F3C
 
@@ -13,3 +16,7 @@ enum PXE_ERR {
     PXE_ERR_NOTENOUGHBUFFER = -54,
     PXE_ERR_INCORRECTDBINDEX = -55,
 };
+
+enum PXE_ERR PXStartPath3Trans(void * tagAddr);
+
+#endif
diff --git a/include/usr/local/sega/px/src/pxvertexbuffer.h b/include/usr/local/sega/px/src/pxvertexbuffer.h
index e69de29..4767222 100644
--- a/include/usr/local/sega/px/src/pxvertexbuffer.h
+++ b/include/usr/local/sega/px/src/pxvertexbuffer.h
@@ -0,0 +1,24 @@
+#ifndef PXVERTEXBUFFER_H
+#define PXVERTEXBUFFER_H
+
+struct PXS_VERTEXBUFFER{
+    char magic[4]; // offset 0x0, size 0x4
+    unsigned int version; // offset 0x4, size 0x4
+    unsigned int size; // offset 0x8, size 0x4
+    unsigned int flag; // offset 0xC, size 0x4
+    __int128 * addr; // offset 0x10, size 0x4
+    unsigned int qwc; // offset 0x14, size 0x4
+    __int128 * bufPtr; // offset 0x18, size 0x4
+    unsigned int lockFlag; // offset 0x1C, size 0x4
+    unsigned int vuOffset; // offset 0x20, size 0x4
+    unsigned int reserved2[3]; // offset 0x24, size 0xC
+    unsigned int reserved3[4]; // offset 0x30, size 0x10
+};
+
+struct PXS_VERTEXBUFFER * PXSetupVB(void * addr, unsigned int size, unsigned int flag);
+void * PXLockVB(struct PXS_VERTEXBUFFER *vb, unsigned int flag);
+void PXUnlockVB(struct PXS_VERTEXBUFFER * vb, void * p);
+void * PXBeginPrimVB(struct PXS_VERTEXBUFFER * vb, void * addr, unsigned int vertices, unsigned int stride, unsigned int prim);
+void * PXEndPrimVB(int /* unused */, void * addr);
+
+#endif
diff --git a/src/usr/local/sega/px/src/pxvertexbuffer.c b/src/usr/local/sega/px/src/pxvertexbuffer.c
index e69de29..e0e7a11 100644
--- a/src/usr/local/sega/px/src/pxvertexbuffer.c
+++ b/src/usr/local/sega/px/src/pxvertexbuffer.c
@@ -0,0 +1,74 @@
+#include "usr/local/sega/px/src/pxvertexbuffer.h"
+#include "usr/local/sce/ee/gcc/ee/lib/libc/memset.h"
+#include "usr/local/sce/ee/lib/eestruct.h"
+
+struct PXS_VERTEXBUFFER * PXSetupVB(void *addr, unsigned int size, unsigned int flag) {
+	struct PXS_VERTEXBUFFER * vb;
+    memset(addr, 0, sizeof(struct PXS_VERTEXBUFFER));
+    vb = (struct PXS_VERTEXBUFFER *) addr;
+    vb->magic[0] = 'P';
+    vb->magic[1] = 'X';
+    vb->magic[2] = 'V';
+    vb->magic[3] = 'B';
+    vb->version = 0x10;
+    vb->addr = (__int128 *)( (char *)addr + sizeof(struct PXS_VERTEXBUFFER));
+    vb->size = size;
+    vb->flag = flag;
+    vb->qwc = 0;
+    vb->bufPtr = vb->addr;
+    vb->lockFlag = 0;
+    vb->vuOffset = 1;
+    return vb;
+}
+
+void * PXLockVB(struct PXS_VERTEXBUFFER *vb, unsigned int flag) {
+    vb->lockFlag = flag;
+    return vb->bufPtr;
+}
+
+void PXUnlockVB(struct PXS_VERTEXBUFFER *vb, void *p) {
+    if (((int) p & 0xF) != 0) {
+        if (((int) p & 0xF) != 0) {
+            do {
+                *(int*)p = 0;
+                ((int*)p)++;
+            } while ((int) p & 0xF);
+        }
+    }
+
+    vb->qwc = (((int) p - (int)vb->addr) / 16);
+    vb->bufPtr = (__int128 *) p;
+}
+
+void * PXBeginPrimVB(struct PXS_VERTEXBUFFER * vb, void * addr, unsigned int vertices, unsigned int stride, unsigned int prim) {
+    int vuaddr;  // not shown in the dwarf
+    unsigned int * p;
+
+    if (vb->vuOffset) {
+        vuaddr = 0x200;
+    } else {
+        vuaddr = 0;
+    }
+    
+    p = (unsigned int *) addr;
+    p[0] = 0x01000404;
+    p[1] = 0;
+    p[2] = 0;
+    p[3] = SCE_VIF1_SET_UNPACK(vuaddr, (vertices * stride) + 2, 12, 0);
+    *(unsigned __int128 *)&p[4] = 0;
+    p[4] = vertices;
+    p[7] = vertices * 0xD0;
+    *(unsigned long *)&p[8] = SCE_GIF_SET_TAG(vertices, 1, 1, prim, 0, 3);
+    *(unsigned long *)&p[10] = 0x412;
+    vb->vuOffset ^= 1;
+    return ((unsigned int *) p) + 12;
+}
+
+void * PXEndPrimVB(int /* unused */, void * addr) {
+	unsigned int *p = (unsigned int *) addr;
+    p[0] = 0x17000000;
+    p[1] = 0;
+    p[2] = 0;
+    p[3] = 0;
+    return &p[4];
+}