14 files changed, 626 insertions, 135 deletions

diff --git a/indra/llrender/CMakeLists.txt b/indra/llrender/CMakeLists.txt
index 7f881c8bb3..ccff7c7a8c 100644
--- a/indra/llrender/CMakeLists.txt
+++ b/indra/llrender/CMakeLists.txt
@@ -17,6 +17,7 @@ set(llrender_SOURCE_FILES
     llfontfreetype.cpp
     llfontfreetypesvg.cpp
     llfontgl.cpp
+    llfontvertexbuffer.cpp
     llfontregistry.cpp
     llgl.cpp
     llglslshader.cpp
@@ -43,6 +44,7 @@ set(llrender_HEADER_FILES
     llcubemap.h
     llcubemaparray.h
     llfontgl.h
+    llfontvertexbuffer.h
     llfontfreetype.h
     llfontfreetypesvg.h
     llfontbitmapcache.h
diff --git a/indra/llrender/llfontgl.cpp b/indra/llrender/llfontgl.cpp
index b6cdb81b33..9721b020c7 100644
--- a/indra/llrender/llfontgl.cpp
+++ b/indra/llrender/llfontgl.cpp
@@ -270,10 +270,10 @@ S32 LLFontGL::render(const LLWString &wstr, S32 begin_offset, F32 x, F32 y, cons
 
     const LLFontGlyphInfo* next_glyph = NULL;
 
-    const S32 GLYPH_BATCH_SIZE = 30;
-    LLVector3 vertices[GLYPH_BATCH_SIZE * 4];
-    LLVector2 uvs[GLYPH_BATCH_SIZE * 4];
-    LLColor4U colors[GLYPH_BATCH_SIZE * 4];
+    static constexpr S32 GLYPH_BATCH_SIZE = 30;
+    static thread_local LLVector3 vertices[GLYPH_BATCH_SIZE * 4];
+    static thread_local LLVector2 uvs[GLYPH_BATCH_SIZE * 4];
+    static thread_local LLColor4U colors[GLYPH_BATCH_SIZE * 4];
 
     LLColor4U text_color(color);
     // Preserve the transparency to render fading emojis in fading text (e.g.
@@ -402,7 +402,6 @@ S32 LLFontGL::render(const LLWString &wstr, S32 begin_offset, F32 x, F32 y, cons
 
     if (draw_ellipses)
     {
-
         // recursively render ellipses at end of string
         // we've already reserved enough room
         gGL.pushUIMatrix();
@@ -504,6 +503,7 @@ F32 LLFontGL::getWidthF32(const std::string& utf8text, S32 begin_offset, S32 max
 
 F32 LLFontGL::getWidthF32(const llwchar* wchars, S32 begin_offset, S32 max_chars, bool no_padding) const
 {
+    LL_PROFILE_ZONE_SCOPED_CATEGORY_UI;
     const S32 LAST_CHARACTER = LLFontFreetype::LAST_CHAR_FULL;
 
     F32 cur_x = 0;
diff --git a/indra/llrender/llfontvertexbuffer.cpp b/indra/llrender/llfontvertexbuffer.cpp
new file mode 100644
index 0000000000..96ec94fe0f
--- /dev/null
+++ b/indra/llrender/llfontvertexbuffer.cpp
@@ -0,0 +1,209 @@
+/**
+ * @file llfontvertexbuffer.cpp
+ * @brief Buffer storage for font rendering.
+ *
+ * $LicenseInfo:firstyear=2024&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2024, Linden Research, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#include "linden_common.h"
+
+#include "llfontvertexbuffer.h"
+
+#include "llvertexbuffer.h"
+
+
+LLFontVertexBuffer::LLFontVertexBuffer()
+{
+}
+
+LLFontVertexBuffer::~LLFontVertexBuffer()
+{
+    reset();
+}
+
+void LLFontVertexBuffer::reset()
+{
+    mBufferList.clear();
+}
+
+S32 LLFontVertexBuffer::render(
+    const LLFontGL* fontp,
+    const LLWString& text,
+    S32 begin_offset,
+    LLRect rect,
+    const LLColor4& color,
+    LLFontGL::HAlign halign, LLFontGL::VAlign valign,
+    U8 style,
+    LLFontGL::ShadowType shadow,
+    S32 max_chars, S32 max_pixels,
+    F32* right_x,
+    bool use_ellipses,
+    bool use_color)
+{
+    LLRectf rect_float((F32)rect.mLeft, (F32)rect.mTop, (F32)rect.mRight, (F32)rect.mBottom);
+    return render(fontp, text, begin_offset, rect_float, color, halign, valign, style, shadow, max_chars, right_x, use_ellipses, use_color);
+}
+
+S32 LLFontVertexBuffer::render(
+    const LLFontGL* fontp,
+    const LLWString& text,
+    S32 begin_offset,
+    LLRectf rect,
+    const LLColor4& color,
+    LLFontGL::HAlign halign, LLFontGL::VAlign valign,
+    U8 style,
+    LLFontGL::ShadowType shadow,
+    S32 max_chars,
+    F32* right_x,
+    bool use_ellipses,
+    bool use_color)
+{
+    F32 x = rect.mLeft;
+    F32 y = 0.f;
+
+    switch (valign)
+    {
+    case LLFontGL::TOP:
+        y = rect.mTop;
+        break;
+    case LLFontGL::VCENTER:
+        y = rect.getCenterY();
+        break;
+    case LLFontGL::BASELINE:
+    case LLFontGL::BOTTOM:
+        y = rect.mBottom;
+        break;
+    default:
+        y = rect.mBottom;
+        break;
+    }
+    return render(fontp, text, begin_offset, x, y, color, halign, valign, style, shadow, max_chars, (S32)rect.getWidth(), right_x, use_ellipses, use_color);
+}
+
+S32 LLFontVertexBuffer::render(
+    const LLFontGL* fontp,
+    const LLWString& text,
+    S32 begin_offset,
+    F32 x, F32 y,
+    const LLColor4& color,
+    LLFontGL::HAlign halign, LLFontGL::VAlign valign,
+    U8 style,
+    LLFontGL::ShadowType shadow,
+    S32 max_chars , S32 max_pixels,
+    F32* right_x,
+    bool use_ellipses,
+    bool use_color )
+{
+    if (!LLFontGL::sDisplayFont) //do not display texts
+    {
+        return static_cast<S32>(text.length());
+    }
+    if (mBufferList.empty())
+    {
+        genBuffers(fontp, text, begin_offset, x, y, color, halign, valign,
+            style, shadow, max_chars, max_pixels, right_x, use_ellipses, use_color);
+    }
+    else if (mLastX != x
+             || mLastY != y
+             || mLastFont != fontp
+             || mLastColor != color // alphas change often
+             || mLastHalign != halign
+             || mLastValign != valign
+             || mLastOffset != begin_offset
+             || mLastMaxChars != max_chars
+             || mLastMaxPixels != max_pixels
+             || mLastStyle != style
+             || mLastShadow != shadow // ex: buttons change shadow state
+             || mLastScaleX != LLFontGL::sScaleX
+             || mLastScaleY != LLFontGL::sScaleY
+             || mLastOrigin != LLFontGL::sCurOrigin)
+    {
+        genBuffers(fontp, text, begin_offset, x, y, color, halign, valign,
+            style, shadow, max_chars, max_pixels, right_x, use_ellipses, use_color);
+    }
+    else
+    {
+        renderBuffers();
+
+        if (right_x)
+        {
+            *right_x = mLastRightX;
+        }
+    }
+    return mChars;
+}
+
+void LLFontVertexBuffer::genBuffers(
+    const LLFontGL* fontp,
+    const LLWString& text,
+    S32 begin_offset,
+    F32 x, F32 y,
+    const LLColor4& color,
+    LLFontGL::HAlign halign, LLFontGL::VAlign valign,
+    U8 style, LLFontGL::ShadowType shadow,
+    S32 max_chars, S32 max_pixels,
+    F32* right_x,
+    bool use_ellipses,
+    bool use_color)
+{
+    // todo: add a debug build assert if this triggers too often for to long?
+    mBufferList.clear();
+
+    gGL.beginList(&mBufferList);
+    mChars = fontp->render(text, begin_offset, x, y, color, halign, valign,
+        style, shadow, max_chars, max_pixels, right_x, use_ellipses, use_color);
+    gGL.endList();
+
+    mLastFont = fontp;
+    mLastOffset = begin_offset;
+    mLastMaxChars = max_chars;
+    mLastMaxPixels = max_pixels;
+    mLastX = x;
+    mLastY = y;
+    mLastColor = color;
+    mLastHalign = halign;
+    mLastValign = valign;
+    mLastStyle = style;
+    mLastShadow = shadow;
+
+    mLastScaleX = LLFontGL::sScaleX;
+    mLastScaleY = LLFontGL::sScaleY;
+    mLastOrigin = LLFontGL::sCurOrigin;
+
+    if (right_x)
+    {
+        mLastRightX = *right_x;
+    }
+}
+
+void LLFontVertexBuffer::renderBuffers()
+{
+    gGL.flush(); // deliberately empty pending verts
+    gGL.getTexUnit(0)->enable(LLTexUnit::TT_TEXTURE);
+    gGL.pushUIMatrix();
+    for (LLVertexBufferData& buffer : mBufferList)
+    {
+        buffer.draw();
+    }
+    gGL.popUIMatrix();
+}
+
diff --git a/indra/llrender/llfontvertexbuffer.h b/indra/llrender/llfontvertexbuffer.h
new file mode 100644
index 0000000000..67cf2ca13c
--- /dev/null
+++ b/indra/llrender/llfontvertexbuffer.h
@@ -0,0 +1,119 @@
+/**
+ * @file llfontgl.h
+ * @author Andrii Kleshchev
+ * @brief Buffer storage for font rendering.
+ *
+ * $LicenseInfo:firstyear=2001&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2010, Linden Research, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#ifndef LL_LLFONTVERTEXBUFFER_H
+#define LL_LLFONTVERTEXBUFFER_H
+
+#include "llfontgl.h"
+
+class LLVertexBufferData;
+
+class LLFontVertexBuffer
+{
+public:
+    LLFontVertexBuffer();
+    ~LLFontVertexBuffer();
+
+    void reset();
+
+    S32 render(const LLFontGL* fontp,
+        const LLWString& text,
+        S32 begin_offset,
+        LLRect rect,
+        const LLColor4& color,
+        LLFontGL::HAlign halign = LLFontGL::LEFT, LLFontGL::VAlign valign = LLFontGL::BASELINE,
+        U8 style = LLFontGL::NORMAL,
+        LLFontGL::ShadowType shadow = LLFontGL::NO_SHADOW,
+        S32 max_chars = S32_MAX, S32 max_pixels = S32_MAX,
+        F32* right_x = NULL,
+        bool use_ellipses = false,
+        bool use_color = true);
+
+    S32 render(const LLFontGL* fontp,
+        const LLWString& text,
+        S32 begin_offset,
+        LLRectf rect,
+        const LLColor4& color,
+        LLFontGL::HAlign halign = LLFontGL::LEFT, LLFontGL::VAlign valign = LLFontGL::BASELINE,
+        U8 style = LLFontGL::NORMAL,
+        LLFontGL::ShadowType shadow = LLFontGL::NO_SHADOW,
+        S32 max_chars = S32_MAX,
+        F32* right_x = NULL,
+        bool use_ellipses = false,
+        bool use_color = true);
+
+    S32 render(const LLFontGL* fontp,
+        const LLWString& text,
+        S32 begin_offset,
+        F32 x, F32 y,
+        const LLColor4& color,
+        LLFontGL::HAlign halign = LLFontGL::LEFT, LLFontGL::VAlign valign = LLFontGL::BASELINE,
+        U8 style = LLFontGL::NORMAL,
+        LLFontGL::ShadowType shadow = LLFontGL::NO_SHADOW,
+        S32 max_chars = S32_MAX, S32 max_pixels = S32_MAX,
+        F32* right_x = NULL,
+        bool use_ellipses = false,
+        bool use_color = true);
+private:
+
+    void genBuffers(const LLFontGL* fontp,
+         const LLWString& text,
+         S32 begin_offset,
+         F32 x, F32 y,
+         const LLColor4& color,
+         LLFontGL::HAlign halign, LLFontGL::VAlign valign,
+         U8 style,
+        LLFontGL::ShadowType shadow,
+         S32 max_chars, S32 max_pixels,
+         F32* right_x,
+         bool use_ellipses,
+         bool use_color);
+
+    void renderBuffers();
+
+    std::list<LLVertexBufferData> mBufferList;
+    S32 mChars = 0;
+    const LLFontGL *mLastFont = nullptr;
+    S32 mLastOffset = 0;
+    S32 mLastMaxChars = 0;
+    S32 mLastMaxPixels = 0;
+    F32 mLastX = 0.f;
+    F32 mLastY = 0.f;
+    LLColor4 mLastColor;
+    LLFontGL::HAlign mLastHalign = LLFontGL::LEFT;
+    LLFontGL::VAlign mLastValign = LLFontGL::BASELINE;
+    U8 mLastStyle = LLFontGL::NORMAL;
+    LLFontGL::ShadowType mLastShadow = LLFontGL::NO_SHADOW;
+    F32 mLastRightX = 0.f;
+
+    // LLFontGL's statics
+    F32 mLastScaleX = 1.f;
+    F32 mLastScaleY = 1.f;
+    LLCoordGL mLastOrigin;
+};
+
+#endif
diff --git a/indra/llrender/llglslshader.cpp b/indra/llrender/llglslshader.cpp
index daa768e8ab..a157bfee21 100644
--- a/indra/llrender/llglslshader.cpp
+++ b/indra/llrender/llglslshader.cpp
@@ -1087,17 +1087,17 @@ void LLGLSLShader::unbind(void)
     sCurBoundShaderPtr = NULL;
 }
 
-S32 LLGLSLShader::bindTexture(const std::string& uniform, LLTexture* texture, LLTexUnit::eTextureType mode, LLTexUnit::eTextureColorSpace colorspace)
+S32 LLGLSLShader::bindTexture(const std::string& uniform, LLTexture* texture, LLTexUnit::eTextureType mode)
 {
     LL_PROFILE_ZONE_SCOPED_CATEGORY_SHADER;
 
     S32 channel = 0;
     channel = getUniformLocation(uniform);
 
-    return bindTexture(channel, texture, mode, colorspace);
+    return bindTexture(channel, texture, mode);
 }
 
-S32 LLGLSLShader::bindTexture(S32 uniform, LLTexture* texture, LLTexUnit::eTextureType mode, LLTexUnit::eTextureColorSpace colorspace)
+S32 LLGLSLShader::bindTexture(S32 uniform, LLTexture* texture, LLTexUnit::eTextureType mode)
 {
     LL_PROFILE_ZONE_SCOPED_CATEGORY_SHADER;
 
@@ -1113,7 +1113,6 @@ S32 LLGLSLShader::bindTexture(S32 uniform, LLTexture* texture, LLTexUnit::eTextu
     if (uniform > -1)
     {
         gGL.getTexUnit(uniform)->bindFast(texture);
-        gGL.getTexUnit(uniform)->setTextureColorSpace(colorspace);
     }
 
     return uniform;
@@ -1194,7 +1193,7 @@ S32 LLGLSLShader::getTextureChannel(S32 uniform) const
     return mTexture[uniform];
 }
 
-S32 LLGLSLShader::enableTexture(S32 uniform, LLTexUnit::eTextureType mode, LLTexUnit::eTextureColorSpace space)
+S32 LLGLSLShader::enableTexture(S32 uniform, LLTexUnit::eTextureType mode)
 {
     LL_PROFILE_ZONE_SCOPED_CATEGORY_SHADER;
 
@@ -1211,12 +1210,11 @@ S32 LLGLSLShader::enableTexture(S32 uniform, LLTexUnit::eTextureType mode, LLTex
     {
         gGL.getTexUnit(index)->activate();
         gGL.getTexUnit(index)->enable(mode);
-        gGL.getTexUnit(index)->setTextureColorSpace(space);
     }
     return index;
 }
 
-S32 LLGLSLShader::disableTexture(S32 uniform, LLTexUnit::eTextureType mode, LLTexUnit::eTextureColorSpace space)
+S32 LLGLSLShader::disableTexture(S32 uniform, LLTexUnit::eTextureType mode)
 {
     LL_PROFILE_ZONE_SCOPED_CATEGORY_SHADER;
 
@@ -1229,7 +1227,7 @@ S32 LLGLSLShader::disableTexture(S32 uniform, LLTexUnit::eTextureType mode, LLTe
     S32 index = mTexture[uniform];
     if (index != -1 && gGL.getTexUnit(index)->getCurrType() != LLTexUnit::TT_NONE)
     {
-        if (gDebugGL && gGL.getTexUnit(index)->getCurrType() != mode && gGL.getTexUnit(index)->getCurrColorSpace() != space)
+        if (gDebugGL && gGL.getTexUnit(index)->getCurrType() != mode)
         {
             if (gDebugSession)
             {
diff --git a/indra/llrender/llglslshader.h b/indra/llrender/llglslshader.h
index f3c41cd819..27c8f0b7d0 100644
--- a/indra/llrender/llglslshader.h
+++ b/indra/llrender/llglslshader.h
@@ -241,6 +241,10 @@ public:
 
     void clearPermutations();
     void addPermutation(std::string name, std::string value);
+    void addPermutations(const std::map<std::string, std::string>& defines)
+    {
+        mDefines.insert(defines.begin(), defines.end());
+    }
     void removePermutation(std::string name);
 
     void addConstant(const LLGLSLShader::eShaderConsts shader_const);
@@ -249,16 +253,16 @@ public:
     //if given texture uniform is active in the shader,
     //the corresponding channel will be active upon return
     //returns channel texture is enabled in from [0-MAX)
-    S32 enableTexture(S32 uniform, LLTexUnit::eTextureType mode = LLTexUnit::TT_TEXTURE, LLTexUnit::eTextureColorSpace space = LLTexUnit::TCS_LINEAR);
-    S32 disableTexture(S32 uniform, LLTexUnit::eTextureType mode = LLTexUnit::TT_TEXTURE, LLTexUnit::eTextureColorSpace space = LLTexUnit::TCS_LINEAR);
+    S32 enableTexture(S32 uniform, LLTexUnit::eTextureType mode = LLTexUnit::TT_TEXTURE);
+    S32 disableTexture(S32 uniform, LLTexUnit::eTextureType mode = LLTexUnit::TT_TEXTURE);
 
     // get the texture channel of the given uniform, or -1 if uniform is not used as a texture
     S32 getTextureChannel(S32 uniform) const;
 
     // bindTexture returns the texture unit we've bound the texture to.
     // You can reuse the return value to unbind a texture when required.
-    S32 bindTexture(const std::string& uniform, LLTexture* texture, LLTexUnit::eTextureType mode = LLTexUnit::TT_TEXTURE, LLTexUnit::eTextureColorSpace space = LLTexUnit::TCS_LINEAR);
-    S32 bindTexture(S32 uniform, LLTexture* texture, LLTexUnit::eTextureType mode = LLTexUnit::TT_TEXTURE, LLTexUnit::eTextureColorSpace space = LLTexUnit::TCS_LINEAR);
+    S32 bindTexture(const std::string& uniform, LLTexture* texture, LLTexUnit::eTextureType mode = LLTexUnit::TT_TEXTURE);
+    S32 bindTexture(S32 uniform, LLTexture* texture, LLTexUnit::eTextureType mode = LLTexUnit::TT_TEXTURE);
     S32 bindTexture(const std::string& uniform, LLRenderTarget* texture, bool depth = false, LLTexUnit::eTextureFilterOptions mode = LLTexUnit::TFO_BILINEAR);
     S32 bindTexture(S32 uniform, LLRenderTarget* texture, bool depth = false, LLTexUnit::eTextureFilterOptions mode = LLTexUnit::TFO_BILINEAR, U32 index = 0);
     S32 unbindTexture(const std::string& uniform, LLTexUnit::eTextureType mode = LLTexUnit::TT_TEXTURE);
diff --git a/indra/llrender/llimagegl.cpp b/indra/llrender/llimagegl.cpp
index 03ac10c00a..68c20048ec 100644
--- a/indra/llrender/llimagegl.cpp
+++ b/indra/llrender/llimagegl.cpp
@@ -70,6 +70,7 @@ static U64 sTextureBytes = 0;
 void LLImageGLMemory::alloc_tex_image(U32 width, U32 height, U32 intformat, U32 count)
 {
     U32 texUnit = gGL.getCurrentTexUnitIndex();
+    llassert(texUnit == 0); // allocations should always be done on tex unit 0
     U32 texName = gGL.getTexUnit(texUnit)->getCurrTexture();
     U64 size = LLImageGL::dataFormatBytes(intformat, width, height);
     size *= count;
@@ -77,6 +78,8 @@ void LLImageGLMemory::alloc_tex_image(U32 width, U32 height, U32 intformat, U32
     llassert(size >= 0);
 
     sTexMemMutex.lock();
+
+    // it is a precondition that no existing allocation exists for this texture
     llassert(sTextureAllocs.find(texName) == sTextureAllocs.end());
 
     sTextureAllocs[texName] = size;
@@ -90,7 +93,7 @@ void LLImageGLMemory::free_tex_image(U32 texName)
 {
     sTexMemMutex.lock();
     auto iter = sTextureAllocs.find(texName);
-    if (iter != sTextureAllocs.end())
+    if (iter != sTextureAllocs.end()) // sometimes a texName will be "freed" before allocated (e.g. first call to setManualImage for a given texName)
     {
         llassert(iter->second <= sTextureBytes); // sTextureBytes MUST NOT go below zero
 
@@ -115,6 +118,7 @@ void LLImageGLMemory::free_tex_images(U32 count, const U32* texNames)
 void LLImageGLMemory::free_cur_tex_image()
 {
     U32 texUnit = gGL.getCurrentTexUnitIndex();
+    llassert(texUnit == 0); // frees should always be done on tex unit 0
     U32 texName = gGL.getTexUnit(texUnit)->getCurrTexture();
     free_tex_image(texName);
 }
@@ -1240,8 +1244,8 @@ void LLImageGL::deleteTextures(S32 numTextures, const U32 *textures)
 
         if (!sFreeList[idx].empty())
         {
-            glDeleteTextures((GLsizei) sFreeList[idx].size(), sFreeList[idx].data());
             free_tex_images((GLsizei) sFreeList[idx].size(), sFreeList[idx].data());
+            glDeleteTextures((GLsizei)sFreeList[idx].size(), sFreeList[idx].data());
             sFreeList[idx].resize(0);
         }
     }
@@ -2461,7 +2465,7 @@ bool LLImageGL::scaleDown(S32 desired_discard)
     { // use a PBO to downscale the texture
         U64 size = getBytes(desired_discard);
         llassert(size <= 2048 * 2048 * 4); // we shouldn't be using this method to downscale huge textures, but it'll work
-        gGL.getTexUnit(0)->bind(this);
+        gGL.getTexUnit(0)->bind(this, false, true);
 
         if (sScratchPBO == 0)
         {
diff --git a/indra/llrender/llrender.cpp b/indra/llrender/llrender.cpp
index 1301d325a0..828a509971 100644
--- a/indra/llrender/llrender.cpp
+++ b/indra/llrender/llrender.cpp
@@ -77,6 +77,7 @@ struct LLVBCache
 };
 
 static std::unordered_map<U64, LLVBCache> sVBCache;
+static thread_local std::list<LLVertexBufferData> *sBufferDataList = nullptr;
 
 static const GLenum sGLTextureType[] =
 {
@@ -115,7 +116,7 @@ static const GLenum sGLBlendFactor[] =
 
 LLTexUnit::LLTexUnit(S32 index)
     : mCurrTexType(TT_NONE),
-    mCurrColorScale(1), mCurrAlphaScale(1), mCurrTexture(0), mTexColorSpace(TCS_LINEAR),
+    mCurrColorScale(1), mCurrAlphaScale(1), mCurrTexture(0),
     mHasMipMaps(false),
     mIndex(index)
 {
@@ -145,8 +146,6 @@ void LLTexUnit::refreshState(void)
     {
         glBindTexture(GL_TEXTURE_2D, 0);
     }
-
-    setTextureColorSpace(mTexColorSpace);
 }
 
 void LLTexUnit::activate(void)
@@ -241,7 +240,6 @@ bool LLTexUnit::bind(LLTexture* texture, bool for_rendering, bool forceBind)
                         setTextureAddressMode(gl_tex->mAddressMode);
                         setTextureFilteringOption(gl_tex->mFilterOption);
                     }
-                    setTextureColorSpace(mTexColorSpace);
                 }
             }
             else
@@ -318,7 +316,6 @@ bool LLTexUnit::bind(LLImageGL* texture, bool for_rendering, bool forceBind, S32
             setTextureFilteringOption(texture->mFilterOption);
             stop_glerror();
         }
-        setTextureColorSpace(mTexColorSpace);
     }
 
     stop_glerror();
@@ -354,7 +351,6 @@ bool LLTexUnit::bind(LLCubeMap* cubeMap)
                 setTextureAddressMode(cubeMap->mImages[0]->mAddressMode);
                 setTextureFilteringOption(cubeMap->mImages[0]->mFilterOption);
             }
-            setTextureColorSpace(mTexColorSpace);
             return true;
         }
         else
@@ -403,7 +399,6 @@ bool LLTexUnit::bindManual(eTextureType type, U32 texture, bool hasMips)
         mCurrTexture = texture;
         glBindTexture(sGLTextureType[type], texture);
         mHasMipMaps = hasMips;
-        setTextureColorSpace(mTexColorSpace);
     }
     return true;
 }
@@ -424,8 +419,6 @@ void LLTexUnit::unbind(eTextureType type)
     {
         mCurrTexture = 0;
 
-        // Always make sure our texture color space is reset to linear.  SRGB sampling should be opt-in in the vast majority of cases.  Also prevents color space "popping".
-        mTexColorSpace = TCS_LINEAR;
         if (type == LLTexUnit::TT_TEXTURE)
         {
             glBindTexture(sGLTextureType[type], sWhiteTexture);
@@ -447,8 +440,6 @@ void LLTexUnit::unbindFast(eTextureType type)
     {
         mCurrTexture = 0;
 
-        // Always make sure our texture color space is reset to linear.  SRGB sampling should be opt-in in the vast majority of cases.  Also prevents color space "popping".
-        mTexColorSpace = TCS_LINEAR;
         if (type == LLTexUnit::TT_TEXTURE)
         {
             glBindTexture(sGLTextureType[type], sWhiteTexture);
@@ -642,11 +633,6 @@ void LLTexUnit::debugTextureUnit(void)
     }
 }
 
-void LLTexUnit::setTextureColorSpace(eTextureColorSpace space)
-{
-    mTexColorSpace = space;
-}
-
 LLLightState::LLLightState(S32 index)
 : mIndex(index),
   mEnabled(false),
@@ -1543,6 +1529,30 @@ void LLRender::clearErrors()
     }
 }
 
+void LLRender::beginList(std::list<LLVertexBufferData> *list)
+{
+    if (sBufferDataList)
+    {
+        LL_ERRS() << "beginList called while another list is open." << LL_ENDL;
+    }
+    llassert(LLGLSLShader::sCurBoundShaderPtr == &gUIProgram);
+    flush();
+    sBufferDataList = list;
+}
+
+void LLRender::endList()
+{
+    if (sBufferDataList)
+    {
+        flush();
+        sBufferDataList = nullptr;
+    }
+    else
+    {
+        llassert(false); // endList called without an open list
+    }
+}
+
 void LLRender::begin(const GLuint& mode)
 {
     if (mode != mMode)
@@ -1585,6 +1595,7 @@ void LLRender::end()
         flush();
     }
 }
+
 void LLRender::flush()
 {
     STOP_GLERROR;
@@ -1633,127 +1644,166 @@ void LLRender::flush()
         if (mBuffer)
         {
 
-            HBXXH64 hash;
+            LLVertexBuffer *vb;
+
             U32 attribute_mask = LLGLSLShader::sCurBoundShaderPtr->mAttributeMask;
 
+            if (sBufferDataList)
+            {
+                vb = genBuffer(attribute_mask, count);
+                sBufferDataList->emplace_back(
+                    vb,
+                    mMode,
+                    count,
+                    gGL.getTexUnit(0)->mCurrTexture,
+                    mMatrix[MM_MODELVIEW][mMatIdx[MM_MODELVIEW]],
+                    mMatrix[MM_PROJECTION][mMatIdx[MM_PROJECTION]],
+                    mMatrix[MM_TEXTURE0][mMatIdx[MM_TEXTURE0]]
+                    );
+            }
+            else
             {
-                LL_PROFILE_ZONE_NAMED_CATEGORY_VERTEX("vb cache hash");
+                vb = bufferfromCache(attribute_mask, count);
+            }
 
-                hash.update((U8*)mVerticesp.get(), count * sizeof(LLVector4a));
-                if (attribute_mask & LLVertexBuffer::MAP_TEXCOORD0)
-                {
-                    hash.update((U8*)mTexcoordsp.get(), count * sizeof(LLVector2));
-                }
+            drawBuffer(vb, mMode, count);
+        }
+        else
+        {
+            // mBuffer is present in main thread and not present in an image thread
+            LL_ERRS() << "A flush call from outside main rendering thread" << LL_ENDL;
+        }
 
-                if (attribute_mask & LLVertexBuffer::MAP_COLOR)
-                {
-                    hash.update((U8*)mColorsp.get(), count * sizeof(LLColor4U));
-                }
+        resetStriders(count);
+    }
+}
 
-                hash.finalize();
-            }
+LLVertexBuffer* LLRender::bufferfromCache(U32 attribute_mask, U32 count)
+{
+    LLVertexBuffer *vb = nullptr;
+    HBXXH64 hash;
 
+    {
+        LL_PROFILE_ZONE_NAMED_CATEGORY_VERTEX("vb cache hash");
 
-            U64 vhash = hash.digest();
+        hash.update((U8*)mVerticesp.get(), count * sizeof(LLVector4a));
+        if (attribute_mask & LLVertexBuffer::MAP_TEXCOORD0)
+        {
+            hash.update((U8*)mTexcoordsp.get(), count * sizeof(LLVector2));
+        }
 
-            // check the VB cache before making a new vertex buffer
-            // This is a giant hack to deal with (mostly) our terrible UI rendering code
-            // that was built on top of OpenGL immediate mode.  Huge performance wins
-            // can be had by not uploading geometry to VRAM unless absolutely necessary.
-            // Most of our usage of the "immediate mode" style draw calls is actually
-            // sending the same geometry over and over again.
-            // To leverage this, we maintain a running hash of the vertex stream being
-            // built up before a flush, and then check that hash against a VB
-            // cache just before creating a vertex buffer in VRAM
-            std::unordered_map<U64, LLVBCache>::iterator cache = sVBCache.find(vhash);
+        if (attribute_mask & LLVertexBuffer::MAP_COLOR)
+        {
+            hash.update((U8*)mColorsp.get(), count * sizeof(LLColor4U));
+        }
 
-            LLPointer<LLVertexBuffer> vb;
+        hash.finalize();
+    }
 
-            if (cache != sVBCache.end())
-            {
-                LL_PROFILE_ZONE_NAMED_CATEGORY_VERTEX("vb cache hit");
-                // cache hit, just use the cached buffer
-                vb = cache->second.vb;
-                cache->second.touched = std::chrono::steady_clock::now();
-            }
-            else
-            {
-                LL_PROFILE_ZONE_NAMED_CATEGORY_VERTEX("vb cache miss");
-                vb = new LLVertexBuffer(attribute_mask);
-                vb->allocateBuffer(count, 0);
+    U64 vhash = hash.digest();
 
-                vb->setBuffer();
+    // check the VB cache before making a new vertex buffer
+    // This is a giant hack to deal with (mostly) our terrible UI rendering code
+    // that was built on top of OpenGL immediate mode.  Huge performance wins
+    // can be had by not uploading geometry to VRAM unless absolutely necessary.
+    // Most of our usage of the "immediate mode" style draw calls is actually
+    // sending the same geometry over and over again.
+    // To leverage this, we maintain a running hash of the vertex stream being
+    // built up before a flush, and then check that hash against a VB
+    // cache just before creating a vertex buffer in VRAM
+    std::unordered_map<U64, LLVBCache>::iterator cache = sVBCache.find(vhash);
 
-                vb->setPositionData((LLVector4a*) mVerticesp.get());
+    if (cache != sVBCache.end())
+    {
+        LL_PROFILE_ZONE_NAMED_CATEGORY_VERTEX("vb cache hit");
+        // cache hit, just use the cached buffer
+        vb = cache->second.vb;
+        cache->second.touched = std::chrono::steady_clock::now();
+    }
+    else
+    {
+        LL_PROFILE_ZONE_NAMED_CATEGORY_VERTEX("vb cache miss");
+        vb = genBuffer(attribute_mask, count);
+
+        sVBCache[vhash] = { vb , std::chrono::steady_clock::now() };
+
+        static U32 miss_count = 0;
+        miss_count++;
+        if (miss_count > 1024)
+        {
+            LL_PROFILE_ZONE_NAMED_CATEGORY_VERTEX("vb cache clean");
+            miss_count = 0;
+            auto now = std::chrono::steady_clock::now();
 
-                if (attribute_mask & LLVertexBuffer::MAP_TEXCOORD0)
+            using namespace std::chrono_literals;
+            // every 1024 misses, clean the cache of any VBs that haven't been touched in the last second
+            for (std::unordered_map<U64, LLVBCache>::iterator iter = sVBCache.begin(); iter != sVBCache.end(); )
+            {
+                if (now - iter->second.touched > 1s)
                 {
-                    vb->setTexCoord0Data(mTexcoordsp.get());
+                    iter = sVBCache.erase(iter);
                 }
-
-                if (attribute_mask & LLVertexBuffer::MAP_COLOR)
+                else
                 {
-                    vb->setColorData(mColorsp.get());
+                    ++iter;
                 }
+            }
+        }
+    }
+    return vb;
+}
 
-#if LL_DARWIN
-                vb->unmapBuffer();
-#endif
-                vb->unbind();
+LLVertexBuffer* LLRender::genBuffer(U32 attribute_mask, S32 count)
+{
+    LLVertexBuffer * vb = new LLVertexBuffer(attribute_mask);
+    vb->allocateBuffer(count, 0);
 
-                sVBCache[vhash] = { vb , std::chrono::steady_clock::now() };
+    vb->setBuffer();
 
-                static U32 miss_count = 0;
-                miss_count++;
-                if (miss_count > 1024)
-                {
-                    LL_PROFILE_ZONE_NAMED_CATEGORY_VERTEX("vb cache clean");
-                    miss_count = 0;
-                    auto now = std::chrono::steady_clock::now();
+    vb->setPositionData((LLVector4a*)mVerticesp.get());
 
-                    using namespace std::chrono_literals;
-                    // every 1024 misses, clean the cache of any VBs that haven't been touched in the last second
-                    for (std::unordered_map<U64, LLVBCache>::iterator iter = sVBCache.begin(); iter != sVBCache.end(); )
-                    {
-                        if (now - iter->second.touched > 1s)
-                        {
-                            iter = sVBCache.erase(iter);
-                        }
-                        else
-                        {
-                            ++iter;
-                        }
-                    }
-                }
-            }
+    if (attribute_mask & LLVertexBuffer::MAP_TEXCOORD0)
+    {
+        vb->setTexCoord0Data(mTexcoordsp.get());
+    }
 
-            vb->setBuffer();
+    if (attribute_mask & LLVertexBuffer::MAP_COLOR)
+    {
+        vb->setColorData(mColorsp.get());
+    }
 
-            if (mMode == LLRender::QUADS && sGLCoreProfile)
-            {
-                vb->drawArrays(LLRender::TRIANGLES, 0, count);
-                mQuadCycle = 1;
-            }
-            else
-            {
-                vb->drawArrays(mMode, 0, count);
-            }
-        }
-        else
-        {
-            // mBuffer is present in main thread and not present in an image thread
-            LL_ERRS() << "A flush call from outside main rendering thread" << LL_ENDL;
-        }
+#if LL_DARWIN
+    vb->unmapBuffer();
+#endif
+    vb->unbind();
 
+    return vb;
+}
 
-        mVerticesp[0] = mVerticesp[count];
-        mTexcoordsp[0] = mTexcoordsp[count];
-        mColorsp[0] = mColorsp[count];
+void LLRender::drawBuffer(LLVertexBuffer* vb, U32 mode, S32 count)
+{
+    vb->setBuffer();
 
-        mCount = 0;
+    if (mode == LLRender::QUADS && sGLCoreProfile)
+    {
+        vb->drawArrays(LLRender::TRIANGLES, 0, count);
+        mQuadCycle = 1;
+    }
+    else
+    {
+        vb->drawArrays(mode, 0, count);
     }
 }
 
+void LLRender::resetStriders(S32 count)
+{
+    mVerticesp[0] = mVerticesp[count];
+    mTexcoordsp[0] = mTexcoordsp[count];
+    mColorsp[0] = mColorsp[count];
+
+    mCount = 0;
+}
+
 void LLRender::vertex3f(const GLfloat& x, const GLfloat& y, const GLfloat& z)
 {
     //the range of mVerticesp, mColorsp and mTexcoordsp is [0, 4095]
diff --git a/indra/llrender/llrender.h b/indra/llrender/llrender.h
index 010ab122b6..39c13e328a 100644
--- a/indra/llrender/llrender.h
+++ b/indra/llrender/llrender.h
@@ -45,12 +45,14 @@
 #include "glh/glh_linear.h"
 
 #include <array>
+#include <list>
 
 class LLVertexBuffer;
 class LLCubeMap;
 class LLImageGL;
 class LLRenderTarget;
-class LLTexture ;
+class LLTexture;
+class LLVertexBufferData;
 
 #define LL_MATRIX_STACK_DEPTH 32
 
@@ -219,17 +221,12 @@ public:
 
     void setHasMipMaps(bool hasMips) { mHasMipMaps = hasMips; }
 
-    void setTextureColorSpace(eTextureColorSpace space);
-
-    eTextureColorSpace getCurrColorSpace() { return mTexColorSpace; }
-
 protected:
     friend class LLRender;
 
     S32                 mIndex;
     U32                 mCurrTexture;
     eTextureType        mCurrTexType;
-    eTextureColorSpace  mTexColorSpace;
     S32                 mCurrColorScale;
     S32                 mCurrAlphaScale;
     bool                mHasMipMaps;
@@ -420,8 +417,15 @@ public:
 
     void flush();
 
+    // if list is set, will store buffers in list for later use, if list isn't set, will use cache
+    void beginList(std::list<LLVertexBufferData> *list);
+    void endList();
+
     void begin(const GLuint& mode);
     void end();
+
+    U8 getMode() const { return mMode; }
+
     void vertex2i(const GLint& x, const GLint& y);
     void vertex2f(const GLfloat& x, const GLfloat& y);
     void vertex3f(const GLfloat& x, const GLfloat& y, const GLfloat& z);
@@ -490,6 +494,11 @@ public:
 private:
     friend class LLLightState;
 
+    LLVertexBuffer* bufferfromCache(U32 attribute_mask, U32 count);
+    LLVertexBuffer* genBuffer(U32 attribute_mask, S32 count);
+    void drawBuffer(LLVertexBuffer* vb, U32 mode, S32 count);
+    void resetStriders(S32 count);
+
     eMatrixMode mMatrixMode;
     U32 mMatIdx[NUM_MATRIX_MODES];
     U32 mMatHash[NUM_MATRIX_MODES];
@@ -520,7 +529,6 @@ private:
 
     std::vector<LLVector3> mUIOffset;
     std::vector<LLVector3> mUIScale;
-
 };
 
 extern F32 gGLModelView[16];
diff --git a/indra/llrender/llrendertarget.cpp b/indra/llrender/llrendertarget.cpp
index 21a0820d32..38bc5ff331 100644
--- a/indra/llrender/llrendertarget.cpp
+++ b/indra/llrender/llrendertarget.cpp
@@ -509,7 +509,6 @@ void LLRenderTarget::bindTexture(U32 index, S32 channel, LLTexUnit::eTextureFilt
     }
 
     gGL.getTexUnit(channel)->setTextureFilteringOption(filter_options);
-    gGL.getTexUnit(channel)->setTextureColorSpace(isSRGB ? LLTexUnit::TCS_SRGB : LLTexUnit::TCS_LINEAR);
 }
 
 void LLRenderTarget::flush()
diff --git a/indra/llrender/llshadermgr.cpp b/indra/llrender/llshadermgr.cpp
index e9608491a4..150277c8df 100644
--- a/indra/llrender/llshadermgr.cpp
+++ b/indra/llrender/llshadermgr.cpp
@@ -597,6 +597,15 @@ GLuint LLShaderMgr::loadShaderFile(const std::string& filename, S32 & shader_lev
         }
     }
 
+    if (type == GL_FRAGMENT_SHADER)
+    {
+        extra_code_text[extra_code_count++] = strdup("#define FRAGMENT_SHADER 1\n");
+    }
+    else
+    {
+        extra_code_text[extra_code_count++] = strdup("#define VERTEX_SHADER 1\n");
+    }
+
     // Use alpha float to store bit flags
     // See: C++: addDeferredAttachment(), shader: frag_data[2]
     extra_code_text[extra_code_count++] = strdup("#define GBUFFER_FLAG_SKIP_ATMOS   0.0 \n"); // atmo kill
@@ -1468,6 +1477,11 @@ void LLShaderMgr::initAttribsAndUniforms()
 
     mReservedUniforms.push_back("debug_normal_draw_length");
 
+    mReservedUniforms.push_back("edgesTex");
+    mReservedUniforms.push_back("areaTex");
+    mReservedUniforms.push_back("searchTex");
+    mReservedUniforms.push_back("blendTex");
+
     llassert(mReservedUniforms.size() == END_RESERVED_UNIFORMS);
 
     std::set<std::string> dupe_check;
diff --git a/indra/llrender/llshadermgr.h b/indra/llrender/llshadermgr.h
index 2b76ef664b..0eb9db6715 100644
--- a/indra/llrender/llshadermgr.h
+++ b/indra/llrender/llshadermgr.h
@@ -332,6 +332,11 @@ public:
 
         DEBUG_NORMAL_DRAW_LENGTH,           //  "debug_normal_draw_length"
 
+        SMAA_EDGE_TEX,                      //  "edgesTex"
+        SMAA_AREA_TEX,                      //  "areaTex"
+        SMAA_SEARCH_TEX,                    //  "searchTex"
+        SMAA_BLEND_TEX,                     //  "blendTex"
+
         END_RESERVED_UNIFORMS
     } eGLSLReservedUniforms;
     // clang-format on
diff --git a/indra/llrender/llvertexbuffer.cpp b/indra/llrender/llvertexbuffer.cpp
index 02afcf12c6..156e300853 100644
--- a/indra/llrender/llvertexbuffer.cpp
+++ b/indra/llrender/llvertexbuffer.cpp
@@ -570,6 +570,54 @@ public:
 
 static LLVBOPool* sVBOPool = nullptr;
 
+void LLVertexBufferData::draw()
+{
+    if (!mVB)
+    {
+        llassert(false);
+        // Not supposed to happen, check buffer generation
+        return;
+    }
+
+    if (mTexName)
+    {
+        gGL.getTexUnit(0)->bindManual(LLTexUnit::TT_TEXTURE, mTexName);
+    }
+    else
+    {
+        gGL.getTexUnit(0)->unbind(LLTexUnit::TT_TEXTURE);
+    }
+
+    gGL.matrixMode(LLRender::MM_MODELVIEW);
+    gGL.pushMatrix();
+    gGL.loadMatrix(mModelView.m);
+    gGL.matrixMode(LLRender::MM_PROJECTION);
+    gGL.pushMatrix();
+    gGL.loadMatrix(mProjection.m);
+    gGL.matrixMode(LLRender::MM_TEXTURE0);
+    gGL.pushMatrix();
+    gGL.loadMatrix(mTexture0.m);
+
+    mVB->setBuffer();
+
+    if (mMode == LLRender::QUADS && LLRender::sGLCoreProfile)
+    {
+        mVB->drawArrays(LLRender::TRIANGLES, 0, mCount);
+    }
+    else
+    {
+        mVB->drawArrays(mMode, 0, mCount);
+    }
+
+    gGL.popMatrix();
+    gGL.matrixMode(LLRender::MM_PROJECTION);
+    gGL.popMatrix();
+    gGL.matrixMode(LLRender::MM_MODELVIEW);
+    gGL.popMatrix();
+}
+
+//============================================================================
+
 //static
 U64 LLVertexBuffer::getBytesAllocated()
 {
diff --git a/indra/llrender/llvertexbuffer.h b/indra/llrender/llvertexbuffer.h
index 4ada0c335b..2a4affdc60 100644
--- a/indra/llrender/llvertexbuffer.h
+++ b/indra/llrender/llvertexbuffer.h
@@ -53,6 +53,37 @@
 //============================================================================
 // base class
 class LLPrivateMemoryPool;
+class LLVertexBuffer;
+
+class LLVertexBufferData
+{
+public:
+    LLVertexBufferData()
+        : mVB(nullptr)
+        , mMode(0)
+        , mCount(0)
+        , mTexName(0)
+    {}
+    LLVertexBufferData(LLVertexBuffer* buffer, U8 mode, U32 count, U32 tex_name, glh::matrix4f model_view, glh::matrix4f projection, glh::matrix4f texture0)
+        : mVB(buffer)
+        , mMode(mode)
+        , mCount(count)
+        , mTexName(tex_name)
+        , mProjection(model_view)
+        , mModelView(projection)
+        , mTexture0(texture0)
+    {}
+    void draw();
+    LLPointer<LLVertexBuffer> mVB;
+    U8 mMode;
+    U32 mCount;
+    U32 mTexName;
+    glh::matrix4f mProjection;
+    glh::matrix4f mModelView;
+    glh::matrix4f mTexture0;
+};
+typedef std::list<LLVertexBufferData> buffer_data_list_t;
+
 class LLVertexBuffer final : public LLRefCount
 {
 public: