Use mumble_ol.dll to render on any 3D application.

MumGay.c

// OverwolfEmulator.cpp : définit le point d'entrée pour l'application console.
//

#include "stdafx.h"
#include <Windows.h>
#include <stdint.h>

#define OVERLAY_MAGIC_NUMBER 0x00000005

struct OverlayMsgHeader {
	unsigned int uiMagic;
	int iLength;
	unsigned int uiType;
};

#define OVERLAY_MSGTYPE_INIT 0
struct OverlayMsgInit {
	unsigned int uiWidth;
	unsigned int uiHeight;
};

#define OVERLAY_MSGTYPE_SHMEM 1
struct OverlayMsgShmem {
	char a_cName[2048];
};

#define OVERLAY_MSGTYPE_BLIT 2
struct OverlayMsgBlit {
	unsigned int x, y, w, h;
};

#define OVERLAY_MSGTYPE_ACTIVE 3
struct OverlayMsgActive {
	unsigned int x, y, w, h;
};

#define OVERLAY_MSGTYPE_PID 4
struct OverlayMsgPid {
	unsigned int pid;
};

#define OVERLAY_MSGTYPE_FPS 5
struct OverlayMsgFps {
	float fps;
};
#define OVERLAY_FPS_INTERVAL 0.25f

#define OVERLAY_MSGTYPE_INTERACTIVE 6
struct OverlayMsgInteractive {
	bool state;
};

struct OverlayMsg {
	union {
		char headerbuffer[1];
		struct OverlayMsgHeader omh;
	};
	union {
		char msgbuffer[1];
		struct OverlayMsgShmem oms;
		struct OverlayMsgInit omi;
		struct OverlayMsgBlit omb;
		struct OverlayMsgActive oma;
		struct OverlayMsgPid omp;
		struct OverlayMsgFps omf;
		struct OverlayMsgInteractive omin;
	};
};

static HANDLE hPipe;
static bool isInit = false;
static DWORD bufferSize = 0;
static HANDLE hMemory = NULL;
static uint8_t* texture = NULL;

bool sendMessage(HANDLE hSocket, const OverlayMsg &om) {
	DWORD dwBytesToWrite = sizeof(OverlayMsgHeader) + om.omh.iLength;
	DWORD dwBytesWritten = dwBytesToWrite;

	if (WriteFile(hSocket, om.headerbuffer, sizeof(OverlayMsgHeader) + om.omh.iLength, &dwBytesWritten, NULL))
		if (dwBytesToWrite == dwBytesWritten)
			return true;

	return false;
}

void RenderThread() {
	while (1) {
		if (hPipe) {
			if (isInit) {
				OverlayMsg om;
				

				sendMessage(hPipe, om);
				om.omh.uiMagic = OVERLAY_MAGIC_NUMBER;
				om.omh.uiType = OVERLAY_MSGTYPE_BLIT;
				om.omh.iLength = sizeof(OverlayMsgBlit);
				om.omb.h = 82;
				om.oma.w = 71;
				om.oma.x = 10;
				om.oma.y = 10;
				memset(texture, rand()%0xFF, bufferSize);
				sendMessage(hPipe, om);

			}
			else if (bufferSize && !texture && !hMemory) { //Initiate Shared Memory
				printf("Shared memory initialization!\n");
				OverlayMsg om;
				om.omh.uiMagic = OVERLAY_MAGIC_NUMBER;
				om.omh.uiType = OVERLAY_MSGTYPE_SHMEM;
				om.omh.iLength = sizeof(OverlayMsgShmem);

				WideCharToMultiByte(CP_UTF8, 0, L"MyFileMappingObject", om.omh.iLength, om.oms.a_cName, 2048, 0, 0);
				hMemory = CreateFileMappingW(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, bufferSize, L"MyFileMappingObject");
				texture = (uint8_t*)MapViewOfFile(hMemory, FILE_MAP_ALL_ACCESS, 0, 0, 0);
				memset(texture, 0x00, bufferSize);
				sendMessage(hPipe, om);
				om.omh.uiMagic = OVERLAY_MAGIC_NUMBER;
				om.omh.uiType = OVERLAY_MSGTYPE_ACTIVE;
				om.omh.iLength = sizeof(OverlayMsgActive);
				om.oma.h = 1080;
				om.oma.w = 1980;
				om.oma.x = 0;
				om.oma.y = 0;

				sendMessage(hPipe, om);
				

			}
		}
		Sleep(1000/240); //240fps
		
	}
}

int main(void)
{

	OverlayMsg buffer;
	DWORD dwRead;

	

	hPipe = CreateNamedPipe(TEXT("\\\\.\\pipe\\MumbleOverlayPipe"),
		PIPE_ACCESS_DUPLEX | PIPE_TYPE_BYTE | PIPE_READMODE_BYTE,   // FILE_FLAG_FIRST_PIPE_INSTANCE is not needed but forces CreateNamedPipe(..) to fail if the pipe already exists...
		PIPE_NOWAIT,
		1,
		1024 * 16,
		1024 * 16,
		NMPWAIT_USE_DEFAULT_WAIT,
		NULL);
	while (hPipe != INVALID_HANDLE_VALUE)
	{
			
			while (ReadFile(hPipe, &buffer, sizeof(buffer) - 1, &dwRead, NULL) != FALSE)
			{
				if (dwRead <= 0) {
					Sleep(4);
					memset(&buffer, 0, sizeof(buffer));
					continue;
				}
				switch (buffer.omh.uiType) {
				case OVERLAY_MSGTYPE_FPS:
					printf("FPS : %f\n", buffer.omf.fps);
					break;
				case OVERLAY_MSGTYPE_PID:
					printf("PID : %08x\n", buffer.omp.pid);
					break;
				case OVERLAY_MSGTYPE_SHMEM:
					printf("Shared Memory success!\n");
					isInit = true;
					break;
				case OVERLAY_MSGTYPE_INIT:
					printf("Init : %d x %d\n", buffer.omi.uiWidth, buffer.omi.uiHeight);
					bufferSize = buffer.omi.uiWidth*buffer.omi.uiHeight * 4;
					if (!hMemory);
						CreateThread(NULL, NULL, (LPTHREAD_START_ROUTINE)RenderThread, 0, 0, 0);
					break;
				default:
					printf("Unknown packet from client\n");
				}
					
				memset(&buffer, 0, sizeof(buffer));
				Sleep(250);
			}
	}

	return 0;
}