MSAA

喵.cpp

/*
修改自 BTE Alpha 的 Renderer

正版默认有 MSAA 并自带一个 FBO
给正版用启动参数加 -nofbo -nomsaa

（很奇怪我的正版不会默认开 MSAA
*/

// 初始化 FBO
{
	/*
	N卡可以开 CSAA 用之前检查一下 GL_NV_framebuffer_multisample_coverage 扩展
	coverageSamples 和 colorSamples 怎么填看 http://www.nvidia.com/object/coverage-sampled-aa.html
	*/
	
	qglGenFramebuffersEXT(1, &s_MSAAFBO.s_hBackBufferFBO);
	qglBindFramebufferEXT(GL_FRAMEBUFFER, s_MSAAFBO.s_hBackBufferFBO);

	qglGenRenderbuffersEXT(1, &s_MSAAFBO.s_hBackBufferCB);
	qglBindRenderbufferEXT(GL_RENDERBUFFER, s_MSAAFBO.s_hBackBufferCB);
	if (qglRenderbufferStorageMultisampleCoverageNV)
		qglRenderbufferStorageMultisampleCoverageNV(GL_RENDERBUFFER, 8, 4, GL_RGBA8_EXT, g_iVideoWidth, g_iVideoHeight);
	else
		qglRenderbufferStorageMultisampleEXT(GL_RENDERBUFFER, 4, GL_RGBA8_EXT, g_iVideoWidth, g_iVideoHeight);
	qglFramebufferRenderbufferEXT(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, s_MSAAFBO.s_hBackBufferCB);

	qglGenRenderbuffersEXT(1, &s_MSAAFBO.s_hBackBufferDB);
	qglBindRenderbufferEXT(GL_RENDERBUFFER, s_MSAAFBO.s_hBackBufferDB);
	if (qglRenderbufferStorageMultisampleCoverageNV)
		qglRenderbufferStorageMultisampleCoverageNV(GL_RENDERBUFFER, 8, 4, GL_DEPTH_COMPONENT24, g_iVideoWidth, g_iVideoHeight);
	else
		qglRenderbufferStorageMultisampleEXT(GL_RENDERBUFFER, 4, GL_DEPTH_COMPONENT24, g_iVideoWidth, g_iVideoHeight);
	qglFramebufferRenderbufferEXT(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, s_MSAAFBO.s_hBackBufferDB);
}

#define R_RENDERVIEW_SIG "\xD9\x05\x80\x75\xEC\x01\xD8\x1D\x8C\x70\xE8\x01\x83\xEC\x14\xDF"
#define R_RENDERVIEW_SIG_NEW "\x55\x8B\xEC\x83\xEC\x14\xD9\x05\x2A\x2A\x2A\x2A\xD8\x1D\x2A\x2A\x2A\x2A\xDF\xE0\xF6\xC4\x44"

// hook
{
	// g_dwEngineBuildnum >= 5971 use R_RENDERVIEW_SIG_NEW
	gRefFuncs.R_RenderView = (void(*)(void))g_pMetaHookAPI->SearchPattern((void *)g_dwEngineBase, g_dwEngineSize, R_RENDERVIEW_SIG, sizeof(R_RENDERVIEW_SIG) - 1);
	
	g_pMetaHookAPI->InlineHook(gRefFuncs.R_RenderView, R_RenderView, (void *&)gRefFuncs.R_RenderView);
}

void R_RenderView(void)
{
	// 先取一下现在的 FBO
	GLint drawFBOId = 0;
	glGetIntegerv(GL_FRAMEBUFFER_BINDING, &drawFBOId);

	// 将默认帧缓冲复制进 MSAA FBO
	qglBindFramebufferEXT(GL_READ_FRAMEBUFFER, drawFBOId);
	qglBindFramebufferEXT(GL_DRAW_FRAMEBUFFER, s_MSAAFBO.s_hBackBufferFBO);
	qglBlitFramebufferEXT(0, 0, g_iVideoWidth, g_iVideoHeight, 0, 0, g_iVideoWidth, g_iVideoHeight, GL_COLOR_BUFFER_BIT, GL_LINEAR);

	gRefFuncs.R_RenderView();
	
	// 画完之后再复制回去
	qglBindFramebufferEXT(GL_READ_FRAMEBUFFER, s_MSAAFBO.s_hBackBufferFBO);
	qglBindFramebufferEXT(GL_DRAW_FRAMEBUFFER, drawFBOId);
	qglBlitFramebufferEXT(0, 0, g_iVideoWidth, g_iVideoHeight, 0, 0, g_iVideoWidth, g_iVideoHeight, GL_COLOR_BUFFER_BIT, GL_LINEAR);
	
	// 最后还原 read FBO
	qglBindFramebufferEXT(GL_READ_FRAMEBUFFER, drawFBOId);
}