Implement OGL sampler cache. Allows binding a texture multiple times with different parameters. Also possibly gives a very small speed improvement.

1 files changed, 133 insertions, 0 deletions

diff --git a/Source/Plugins/Plugin_VideoOGL/Src/SamplerCache.cpp b/Source/Plugins/Plugin_VideoOGL/Src/SamplerCache.cpp
new file mode 100644
index 0000000000..b0e6e1f8aa
--- /dev/null
+++ b/Source/Plugins/Plugin_VideoOGL/Src/SamplerCache.cpp
@@ -0,0 +1,133 @@
+// Copyright (C) 2003 Dolphin Project.
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, version 2.0.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License 2.0 for more details.
+
+// A copy of the GPL 2.0 should have been included with the program.
+// If not, see http://www.gnu.org/licenses/
+
+// Official SVN repository and contact information can be found at
+// http://code.google.com/p/dolphin-emu/
+
+#include "SamplerCache.h"
+
+namespace OGL
+{
+
+SamplerCache::SamplerCache()
+	: m_last_max_anisotropy()
+{}
+
+SamplerCache::~SamplerCache()
+{
+	Clear();
+}
+
+void SamplerCache::SetSamplerState(int stage, const TexMode0& tm0, const TexMode1& tm1)
+{
+	// TODO: can this go somewhere else?
+	if (m_last_max_anisotropy != g_ActiveConfig.iMaxAnisotropy)
+	{
+		m_last_max_anisotropy = g_ActiveConfig.iMaxAnisotropy;
+		Clear();
+	}
+	
+	Params params(tm0, tm1);
+	
+	// take equivalent forced linear when bForceFiltering
+	if (g_ActiveConfig.bForceFiltering)
+	{
+		params.tm0.min_filter |= 0x4;
+		params.tm0.mag_filter |= 0x1;
+	}
+	
+	// TODO: Should keep a circular buffer for each stage of recently used samplers.
+	
+	auto const& active_sampler = m_active_samplers[stage];
+	if (active_sampler.first != params || !active_sampler.second.sampler_id)
+	{
+		// Active sampler does not match parameters (or is invalid), bind the proper one.
+		auto const new_sampler = GetEntry(params);
+		
+		glBindSampler(stage, new_sampler.second.sampler_id);
+		m_active_samplers[stage] = new_sampler;
+	}
+	
+	//active_it->second.last_frame_used = frameCount;
+}
+
+auto SamplerCache::GetEntry(const Params& params) -> std::pair<Params, Value>
+{
+	auto it = m_cache.find(params);
+	if (m_cache.end() == it)
+	{
+		// Sampler not found in cache, create it.
+		Value val;
+		glGenSamplers(1, &val.sampler_id);
+		SetParameters(val.sampler_id, params);
+		
+		it = m_cache.insert(std::make_pair(params, val)).first;
+		
+		// TODO: Maybe kill old samplers if the cache gets huge. It doesn't seem to get huge though.
+		//ERROR_LOG(VIDEO, "Sampler cache size is now %ld.", m_cache.size());
+	}
+	
+	return *it;
+}
+
+void SamplerCache::SetParameters(GLuint sampler_id, const Params& params)
+{
+	static const GLint min_filters[8] =
+	{
+		GL_NEAREST,
+		GL_NEAREST_MIPMAP_NEAREST,
+		GL_NEAREST_MIPMAP_LINEAR,
+		GL_NEAREST,
+		GL_LINEAR,
+		GL_LINEAR_MIPMAP_NEAREST,
+		GL_LINEAR_MIPMAP_LINEAR,
+		GL_LINEAR,
+	};
+	
+	static const GLint wrap_settings[4] =
+	{
+		GL_CLAMP_TO_EDGE,
+		GL_REPEAT,
+		GL_MIRRORED_REPEAT,
+		GL_REPEAT,
+	};
+	
+	auto& tm0 = params.tm0;
+	auto& tm1 = params.tm1;
+
+	glSamplerParameteri(sampler_id, GL_TEXTURE_MIN_FILTER, min_filters[tm0.min_filter % ARRAYSIZE(min_filters)]);
+	glSamplerParameteri(sampler_id, GL_TEXTURE_MAG_FILTER, tm0.mag_filter ? GL_LINEAR : GL_NEAREST);
+
+	glSamplerParameteri(sampler_id, GL_TEXTURE_WRAP_S, wrap_settings[tm0.wrap_s]);
+	glSamplerParameteri(sampler_id, GL_TEXTURE_WRAP_T, wrap_settings[tm0.wrap_t]);
+	
+	glSamplerParameterf(sampler_id, GL_TEXTURE_LOD_BIAS, tm0.lod_bias / 32.f);
+	
+	glSamplerParameterf(sampler_id, GL_TEXTURE_MIN_LOD, tm1.min_lod / 16.f);
+	glSamplerParameterf(sampler_id, GL_TEXTURE_MAX_LOD, tm1.max_lod / 16.f);
+
+	if (g_ActiveConfig.iMaxAnisotropy > 0)
+		glSamplerParameterf(sampler_id, GL_TEXTURE_MAX_ANISOTROPY_EXT, (float)(1 << g_ActiveConfig.iMaxAnisotropy));
+}
+
+void SamplerCache::Clear()
+{
+	for (auto it = m_cache.begin(); it != m_cache.end(); ++it)
+	{
+		glDeleteSamplers(1, &it->second.sampler_id);
+	}
+	m_cache.clear();
+}
+
+}