Replace glh_linear usage with GLM (#2554)

6 files changed, 155 insertions, 170 deletions

diff --git a/indra/llrender/llgl.cpp b/indra/llrender/llgl.cpp
index 0db1e27b01..c62cacdce6 100644
--- a/indra/llrender/llgl.cpp
+++ b/indra/llrender/llgl.cpp
@@ -50,6 +50,10 @@
 #include "llglheaders.h"
 #include "llglslshader.h"
 
+#include "glm/glm.hpp"
+#include <glm/gtc/matrix_access.hpp>
+#include "glm/gtc/type_ptr.hpp"
+
 #if LL_WINDOWS
 #include "lldxhardware.h"
 #endif
@@ -2694,7 +2698,7 @@ void parse_glsl_version(S32& major, S32& minor)
     LLStringUtil::convertToS32(minor_str, minor);
 }
 
-LLGLUserClipPlane::LLGLUserClipPlane(const LLPlane& p, const glh::matrix4f& modelview, const glh::matrix4f& projection, bool apply)
+LLGLUserClipPlane::LLGLUserClipPlane(const LLPlane& p, const glm::mat4& modelview, const glm::mat4& projection, bool apply)
 {
     mApply = apply;
 
@@ -2721,13 +2725,12 @@ void LLGLUserClipPlane::disable()
 
 void LLGLUserClipPlane::setPlane(F32 a, F32 b, F32 c, F32 d)
 {
-    glh::matrix4f& P = mProjection;
-    glh::matrix4f& M = mModelview;
+    const glm::mat4& P = mProjection;
+    const glm::mat4& M = mModelview;
 
-    glh::matrix4f invtrans_MVP = (P * M).inverse().transpose();
-    glh::vec4f oplane(a,b,c,d);
-    glh::vec4f cplane;
-    invtrans_MVP.mult_matrix_vec(oplane, cplane);
+    glm::mat4 invtrans_MVP = glm::transpose(glm::inverse(P*M));
+    glm::vec4 oplane(a,b,c,d);
+    glm::vec4 cplane = invtrans_MVP * oplane;
 
     cplane /= fabs(cplane[2]); // normalize such that depth is not scaled
     cplane[3] -= 1;
@@ -2735,13 +2738,13 @@ void LLGLUserClipPlane::setPlane(F32 a, F32 b, F32 c, F32 d)
     if(cplane[2] < 0)
         cplane *= -1;
 
-    glh::matrix4f suffix;
-    suffix.set_row(2, cplane);
-    glh::matrix4f newP = suffix * P;
+    glm::mat4 suffix;
+    suffix = glm::row(suffix, 2, cplane);
+    glm::mat4 newP = suffix * P;
     gGL.matrixMode(LLRender::MM_PROJECTION);
     gGL.pushMatrix();
-    gGL.loadMatrix(newP.m);
-    gGLObliqueProjectionInverse = LLMatrix4(newP.inverse().transpose().m);
+    gGL.loadMatrix(glm::value_ptr(newP));
+    gGLObliqueProjectionInverse = LLMatrix4(glm::value_ptr(glm::transpose(glm::inverse(newP))));
     gGL.matrixMode(LLRender::MM_MODELVIEW);
 }
 
@@ -2838,31 +2841,27 @@ void LLGLDepthTest::checkState()
 
 LLGLSquashToFarClip::LLGLSquashToFarClip()
 {
-    glh::matrix4f proj = get_current_projection();
+    glm::mat4 proj = get_current_projection();
     setProjectionMatrix(proj, 0);
 }
 
-LLGLSquashToFarClip::LLGLSquashToFarClip(glh::matrix4f& P, U32 layer)
+LLGLSquashToFarClip::LLGLSquashToFarClip(const glm::mat4& P, U32 layer)
 {
     setProjectionMatrix(P, layer);
 }
 
-
-void LLGLSquashToFarClip::setProjectionMatrix(glh::matrix4f& projection, U32 layer)
+void LLGLSquashToFarClip::setProjectionMatrix(glm::mat4 projection, U32 layer)
 {
-
     F32 depth = 0.99999f - 0.0001f * layer;
 
-    for (U32 i = 0; i < 4; i++)
-    {
-        projection.element(2, i) = projection.element(3, i) * depth;
-    }
+    glm::vec4 P_row_3 = glm::row(projection, 3) * depth;
+    projection = glm::row(projection, 2, P_row_3);
 
     LLRender::eMatrixMode last_matrix_mode = gGL.getMatrixMode();
 
     gGL.matrixMode(LLRender::MM_PROJECTION);
     gGL.pushMatrix();
-    gGL.loadMatrix(projection.m);
+    gGL.loadMatrix(glm::value_ptr(projection));
 
     gGL.matrixMode(last_matrix_mode);
 }
diff --git a/indra/llrender/llgl.h b/indra/llrender/llgl.h
index cd1ba55b16..17f825bd71 100644
--- a/indra/llrender/llgl.h
+++ b/indra/llrender/llgl.h
@@ -43,7 +43,7 @@
 #include "llinstancetracker.h"
 
 #include "llglheaders.h"
-#include "glh/glh_linear.h"
+#include "glm/mat4x4.hpp"
 
 extern bool gDebugGL;
 extern bool gDebugSession;
@@ -317,7 +317,7 @@ class LLGLUserClipPlane
 {
 public:
 
-    LLGLUserClipPlane(const LLPlane& plane, const glh::matrix4f& modelview, const glh::matrix4f& projection, bool apply = true);
+    LLGLUserClipPlane(const LLPlane& plane, const glm::mat4& modelview, const glm::mat4& projection, bool apply = true);
     ~LLGLUserClipPlane();
 
     void setPlane(F32 a, F32 b, F32 c, F32 d);
@@ -326,8 +326,8 @@ public:
 private:
     bool mApply;
 
-    glh::matrix4f mProjection;
-    glh::matrix4f mModelview;
+    glm::mat4 mProjection;
+    glm::mat4 mModelview;
 };
 
 /*
@@ -341,9 +341,9 @@ class LLGLSquashToFarClip
 {
 public:
     LLGLSquashToFarClip();
-    LLGLSquashToFarClip(glh::matrix4f& projection, U32 layer = 0);
+    LLGLSquashToFarClip(const glm::mat4& projection, U32 layer = 0);
 
-    void setProjectionMatrix(glh::matrix4f& projection, U32 layer);
+    void setProjectionMatrix(glm::mat4 projection, U32 layer);
 
     ~LLGLSquashToFarClip();
 };
diff --git a/indra/llrender/llrender.cpp b/indra/llrender/llrender.cpp
index 828a509971..16a8309a9a 100644
--- a/indra/llrender/llrender.cpp
+++ b/indra/llrender/llrender.cpp
@@ -36,6 +36,7 @@
 #include "lltexture.h"
 #include "llshadermgr.h"
 #include "hbxxh.h"
+#include "glm/gtc/type_ptr.hpp"
 
 #if LL_WINDOWS
 extern void APIENTRY gl_debug_callback(GLenum source,
@@ -57,8 +58,8 @@ F32 gGLLastProjection[16];
 F32 gGLProjection[16];
 
 // transform from last frame's camera space to this frame's camera space (and inverse)
-F32 gGLDeltaModelView[16];
-F32 gGLInverseDeltaModelView[16];
+glm::mat4 gGLDeltaModelView;
+glm::mat4 gGLInverseDeltaModelView;
 
 S32 gGLViewport[4];
 
@@ -735,10 +736,10 @@ void LLLightState::setPosition(const LLVector4& position)
     ++gGL.mLightHash;
     mPosition = position;
     //transform position by current modelview matrix
-    glh::vec4f pos(position.mV);
-    const glh::matrix4f& mat = gGL.getModelviewMatrix();
-    mat.mult_matrix_vec(pos);
-    mPosition.set(pos.v);
+    glm::vec4 pos(glm::make_vec4(position.mV));
+    const glm::mat4& mat = gGL.getModelviewMatrix();
+    pos = mat * pos;
+    mPosition.set(glm::value_ptr(pos));
 }
 
 void LLLightState::setConstantAttenuation(const F32& atten)
@@ -790,13 +791,13 @@ void LLLightState::setSpotDirection(const LLVector3& direction)
 {
     //always set direction because modelview matrix may have changed
     ++gGL.mLightHash;
-    mSpotDirection = direction;
+
     //transform direction by current modelview matrix
-    glh::vec3f dir(direction.mV);
-    const glh::matrix4f& mat = gGL.getModelviewMatrix();
-    mat.mult_matrix_dir(dir);
+    glm::vec3 dir(glm::make_vec3(direction.mV));
+    const glm::mat3 mat(gGL.getModelviewMatrix());
+    dir = mat * dir;
 
-    mSpotDirection.set(dir.v);
+    mSpotDirection.set(glm::value_ptr(dir));
 }
 
 LLRender::LLRender()
@@ -830,6 +831,10 @@ LLRender::LLRender()
 
     for (U32 i = 0; i < NUM_MATRIX_MODES; ++i)
     {
+        for (U32 j = 0; j < LL_MATRIX_STACK_DEPTH; ++j)
+        {
+            mMatrix[i][j] = glm::identity<glm::mat4>();
+        }
         mMatIdx[i] = 0;
         mMatHash[i] = 0;
         mCurMatHash[i] = 0xFFFFFFFF;
@@ -991,12 +996,12 @@ void LLRender::syncMatrices()
 
     LLGLSLShader* shader = LLGLSLShader::sCurBoundShaderPtr;
 
-    static glh::matrix4f cached_mvp;
-    static glh::matrix4f cached_inv_mdv;
+    static glm::mat4 cached_mvp;
+    static glm::mat4 cached_inv_mdv;
     static U32 cached_mvp_mdv_hash = 0xFFFFFFFF;
     static U32 cached_mvp_proj_hash = 0xFFFFFFFF;
 
-    static glh::matrix4f cached_normal;
+    static glm::mat4 cached_normal;
     static U32 cached_normal_hash = 0xFFFFFFFF;
 
     if (shader)
@@ -1006,15 +1011,15 @@ void LLRender::syncMatrices()
         U32 i = MM_MODELVIEW;
         if (mMatHash[MM_MODELVIEW] != shader->mMatHash[MM_MODELVIEW])
         { //update modelview, normal, and MVP
-            glh::matrix4f& mat = mMatrix[MM_MODELVIEW][mMatIdx[MM_MODELVIEW]];
+            const glm::mat4& mat = mMatrix[MM_MODELVIEW][mMatIdx[MM_MODELVIEW]];
 
             // if MDV has changed, update the cached inverse as well
             if (cached_mvp_mdv_hash != mMatHash[MM_MODELVIEW])
             {
-                cached_inv_mdv = mat.inverse();
+                cached_inv_mdv = glm::inverse(mat);
             }
 
-            shader->uniformMatrix4fv(name[MM_MODELVIEW], 1, GL_FALSE, mat.m);
+            shader->uniformMatrix4fv(name[MM_MODELVIEW], 1, GL_FALSE, glm::value_ptr(mat));
             shader->mMatHash[MM_MODELVIEW] = mMatHash[MM_MODELVIEW];
 
             //update normal matrix
@@ -1023,17 +1028,17 @@ void LLRender::syncMatrices()
             {
                 if (cached_normal_hash != mMatHash[i])
                 {
-                    cached_normal = cached_inv_mdv.transpose();
+                    cached_normal = glm::transpose(cached_inv_mdv);
                     cached_normal_hash = mMatHash[i];
                 }
 
-                glh::matrix4f& norm = cached_normal;
+                auto norm = glm::value_ptr(cached_normal);
 
                 F32 norm_mat[] =
                 {
-                    norm.m[0], norm.m[1], norm.m[2],
-                    norm.m[4], norm.m[5], norm.m[6],
-                    norm.m[8], norm.m[9], norm.m[10]
+                    norm[0], norm[1], norm[2],
+                    norm[4], norm[5], norm[6],
+                    norm[8], norm[9], norm[10]
                 };
 
                 shader->uniformMatrix3fv(LLShaderMgr::NORMAL_MATRIX, 1, GL_FALSE, norm_mat);
@@ -1041,7 +1046,7 @@ void LLRender::syncMatrices()
 
             if (shader->getUniformLocation(LLShaderMgr::INVERSE_MODELVIEW_MATRIX))
             {
-                shader->uniformMatrix4fv(LLShaderMgr::INVERSE_MODELVIEW_MATRIX, 1, GL_FALSE, cached_inv_mdv.m);
+                shader->uniformMatrix4fv(LLShaderMgr::INVERSE_MODELVIEW_MATRIX, 1, GL_FALSE, glm::value_ptr(cached_inv_mdv));
             }
 
             //update MVP matrix
@@ -1054,36 +1059,36 @@ void LLRender::syncMatrices()
                 if (cached_mvp_mdv_hash != mMatHash[i] || cached_mvp_proj_hash != mMatHash[MM_PROJECTION])
                 {
                     cached_mvp = mat;
-                    cached_mvp.mult_left(mMatrix[proj][mMatIdx[proj]]);
+                    cached_mvp = mMatrix[proj][mMatIdx[proj]] * cached_mvp;
                     cached_mvp_mdv_hash = mMatHash[i];
                     cached_mvp_proj_hash = mMatHash[MM_PROJECTION];
                 }
 
-                shader->uniformMatrix4fv(LLShaderMgr::MODELVIEW_PROJECTION_MATRIX, 1, GL_FALSE, cached_mvp.m);
+                shader->uniformMatrix4fv(LLShaderMgr::MODELVIEW_PROJECTION_MATRIX, 1, GL_FALSE, glm::value_ptr(cached_mvp));
             }
         }
 
         i = MM_PROJECTION;
         if (mMatHash[MM_PROJECTION] != shader->mMatHash[MM_PROJECTION])
         { //update projection matrix, normal, and MVP
-            glh::matrix4f& mat = mMatrix[MM_PROJECTION][mMatIdx[MM_PROJECTION]];
+            const glm::mat4& mat = mMatrix[MM_PROJECTION][mMatIdx[MM_PROJECTION]];
 
             // GZ: This was previously disabled seemingly due to a bug involving the deferred renderer's regular pushing and popping of mats.
             // We're reenabling this and cleaning up the code around that - that would've been the appropriate course initially.
             // Anything beyond the standard proj and inv proj mats are special cases.  Please setup special uniforms accordingly in the future.
             if (shader->getUniformLocation(LLShaderMgr::INVERSE_PROJECTION_MATRIX))
             {
-                glh::matrix4f inv_proj = mat.inverse();
-                shader->uniformMatrix4fv(LLShaderMgr::INVERSE_PROJECTION_MATRIX, 1, false, inv_proj.m);
+                glm::mat4 inv_proj = glm::inverse(mat);
+                shader->uniformMatrix4fv(LLShaderMgr::INVERSE_PROJECTION_MATRIX, 1, false, glm::value_ptr(inv_proj));
             }
 
             // Used by some full screen effects - such as full screen lights, glow, etc.
             if (shader->getUniformLocation(LLShaderMgr::IDENTITY_MATRIX))
             {
-                shader->uniformMatrix4fv(LLShaderMgr::IDENTITY_MATRIX, 1, GL_FALSE, glh::matrix4f::identity().m);
+                shader->uniformMatrix4fv(LLShaderMgr::IDENTITY_MATRIX, 1, GL_FALSE, glm::value_ptr(glm::identity<glm::mat4>()));
             }
 
-            shader->uniformMatrix4fv(name[MM_PROJECTION], 1, GL_FALSE, mat.m);
+            shader->uniformMatrix4fv(name[MM_PROJECTION], 1, GL_FALSE, glm::value_ptr(mat));
             shader->mMatHash[MM_PROJECTION] = mMatHash[MM_PROJECTION];
 
             if (!mvp_done)
@@ -1096,12 +1101,12 @@ void LLRender::syncMatrices()
                     {
                         U32 mdv = MM_MODELVIEW;
                         cached_mvp = mat;
-                        cached_mvp.mult_right(mMatrix[mdv][mMatIdx[mdv]]);
+                        cached_mvp *= mMatrix[mdv][mMatIdx[mdv]];
                         cached_mvp_mdv_hash = mMatHash[MM_MODELVIEW];
                         cached_mvp_proj_hash = mMatHash[MM_PROJECTION];
                     }
 
-                    shader->uniformMatrix4fv(LLShaderMgr::MODELVIEW_PROJECTION_MATRIX, 1, GL_FALSE, cached_mvp.m);
+                    shader->uniformMatrix4fv(LLShaderMgr::MODELVIEW_PROJECTION_MATRIX, 1, GL_FALSE, glm::value_ptr(cached_mvp));
                 }
             }
         }
@@ -1110,7 +1115,7 @@ void LLRender::syncMatrices()
         {
             if (mMatHash[i] != shader->mMatHash[i])
             {
-                shader->uniformMatrix4fv(name[i], 1, GL_FALSE, mMatrix[i][mMatIdx[i]].m);
+                shader->uniformMatrix4fv(name[i], 1, GL_FALSE, glm::value_ptr(mMatrix[i][mMatIdx[i]]));
                 shader->mMatHash[i] = mMatHash[i];
             }
         }
@@ -1129,12 +1134,7 @@ void LLRender::translatef(const GLfloat& x, const GLfloat& y, const GLfloat& z)
     flush();
 
     {
-        glh::matrix4f trans_mat(1,0,0,x,
-                                0,1,0,y,
-                                0,0,1,z,
-                                0,0,0,1);
-
-        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]].mult_right(trans_mat);
+        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]] = glm::translate(mMatrix[mMatrixMode][mMatIdx[mMatrixMode]], glm::vec3(x, y, z));
         mMatHash[mMatrixMode]++;
     }
 }
@@ -1144,12 +1144,7 @@ void LLRender::scalef(const GLfloat& x, const GLfloat& y, const GLfloat& z)
     flush();
 
     {
-        glh::matrix4f scale_mat(x,0,0,0,
-                                0,y,0,0,
-                                0,0,z,0,
-                                0,0,0,1);
-
-        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]].mult_right(scale_mat);
+        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]] = glm::scale(mMatrix[mMatrixMode][mMatIdx[mMatrixMode]], glm::vec3(x, y, z));
         mMatHash[mMatrixMode]++;
     }
 }
@@ -1159,13 +1154,7 @@ void LLRender::ortho(F32 left, F32 right, F32 bottom, F32 top, F32 zNear, F32 zF
     flush();
 
     {
-
-        glh::matrix4f ortho_mat(2.f/(right-left),0,0,   -(right+left)/(right-left),
-                                0,2.f/(top-bottom),0,   -(top+bottom)/(top-bottom),
-                                0,0,-2.f/(zFar-zNear),  -(zFar+zNear)/(zFar-zNear),
-                                0,0,0,1);
-
-        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]].mult_right(ortho_mat);
+        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]] *= glm::ortho(left, right, bottom, top, zNear, zFar);
         mMatHash[mMatrixMode]++;
     }
 }
@@ -1175,19 +1164,7 @@ void LLRender::rotatef(const GLfloat& a, const GLfloat& x, const GLfloat& y, con
     flush();
 
     {
-        F32 r = a * DEG_TO_RAD;
-
-        F32 c = cosf(r);
-        F32 s = sinf(r);
-
-        F32 ic = 1.f-c;
-
-        glh::matrix4f rot_mat(x*x*ic+c,     x*y*ic-z*s,     x*z*ic+y*s,     0,
-                              x*y*ic+z*s,   y*y*ic+c,       y*z*ic-x*s,     0,
-                              x*z*ic-y*s,   y*z*ic+x*s,     z*z*ic+c,       0,
-                              0,0,0,1);
-
-        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]].mult_right(rot_mat);
+        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]] = glm::rotate(mMatrix[mMatrixMode][mMatIdx[mMatrixMode]], glm::radians(a), glm::vec3(x,y,z));
         mMatHash[mMatrixMode]++;
     }
 }
@@ -1229,7 +1206,7 @@ void LLRender::loadMatrix(const GLfloat* m)
 {
     flush();
     {
-        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]].set_value((GLfloat*) m);
+        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]] = glm::make_mat4((GLfloat*) m);
         mMatHash[mMatrixMode]++;
     }
 }
@@ -1238,9 +1215,7 @@ void LLRender::multMatrix(const GLfloat* m)
 {
     flush();
     {
-        glh::matrix4f mat((GLfloat*) m);
-
-        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]].mult_right(mat);
+        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]] *= glm::make_mat4(m);
         mMatHash[mMatrixMode]++;
     }
 }
@@ -1283,17 +1258,17 @@ void LLRender::loadIdentity()
     {
         llassert_always(mMatrixMode < NUM_MATRIX_MODES) ;
 
-        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]].make_identity();
+        mMatrix[mMatrixMode][mMatIdx[mMatrixMode]] = glm::identity<glm::mat4>();
         mMatHash[mMatrixMode]++;
     }
 }
 
-const glh::matrix4f& LLRender::getModelviewMatrix()
+const glm::mat4& LLRender::getModelviewMatrix()
 {
     return mMatrix[MM_MODELVIEW][mMatIdx[MM_MODELVIEW]];
 }
 
-const glh::matrix4f& LLRender::getProjectionMatrix()
+const glm::mat4& LLRender::getProjectionMatrix()
 {
     return mMatrix[MM_PROJECTION][mMatIdx[MM_PROJECTION]];
 }
@@ -2214,85 +2189,90 @@ void LLRender::debugTexUnits(void)
     LL_INFOS("TextureUnit") << "Active TexUnit Enabled : " << active_enabled << LL_ENDL;
 }
 
-
-
-glh::matrix4f copy_matrix(F32* src)
-{
-    glh::matrix4f ret;
-    ret.set_value(src);
-    return ret;
-}
-
-glh::matrix4f get_current_modelview()
+glm::mat4 get_current_modelview()
 {
-    return copy_matrix(gGLModelView);
+    return glm::make_mat4(gGLModelView);
 }
 
-glh::matrix4f get_current_projection()
+glm::mat4 get_current_projection()
 {
-    return copy_matrix(gGLProjection);
+    return glm::make_mat4(gGLProjection);
 }
 
-glh::matrix4f get_last_modelview()
+glm::mat4 get_last_modelview()
 {
-    return copy_matrix(gGLLastModelView);
+    return glm::make_mat4(gGLLastModelView);
 }
 
-glh::matrix4f get_last_projection()
+glm::mat4 get_last_projection()
 {
-    return copy_matrix(gGLLastProjection);
+    return glm::make_mat4(gGLLastProjection);
 }
 
-void copy_matrix(const glh::matrix4f& src, F32* dst)
+void copy_matrix(const glm::mat4& src, F32* dst)
 {
+    auto matp = glm::value_ptr(src);
     for (U32 i = 0; i < 16; i++)
     {
-        dst[i] = src.m[i];
+        dst[i] = matp[i];
     }
 }
 
-void set_current_modelview(const glh::matrix4f& mat)
+void set_current_modelview(const glm::mat4& mat)
 {
     copy_matrix(mat, gGLModelView);
 }
 
-void set_current_projection(glh::matrix4f& mat)
+void set_current_projection(const glm::mat4& mat)
 {
     copy_matrix(mat, gGLProjection);
 }
 
-glh::matrix4f gl_ortho(GLfloat left, GLfloat right, GLfloat bottom, GLfloat top, GLfloat znear, GLfloat zfar)
+void set_last_modelview(const glm::mat4& mat)
 {
-    glh::matrix4f ret(
-        2.f/(right-left), 0.f, 0.f, -(right+left)/(right-left),
-        0.f, 2.f/(top-bottom), 0.f, -(top+bottom)/(top-bottom),
-        0.f, 0.f, -2.f/(zfar-znear),  -(zfar+znear)/(zfar-znear),
-        0.f, 0.f, 0.f, 1.f);
-
-    return ret;
+    copy_matrix(mat, gGLLastModelView);
 }
 
-glh::matrix4f gl_perspective(GLfloat fovy, GLfloat aspect, GLfloat zNear, GLfloat zFar)
+void set_last_projection(const glm::mat4& mat)
 {
-    GLfloat f = 1.f/tanf(DEG_TO_RAD*fovy/2.f);
-
-    return glh::matrix4f(f/aspect, 0, 0, 0,
-                         0, f, 0, 0,
-                         0, 0, (zFar+zNear)/(zNear-zFar), (2.f*zFar*zNear)/(zNear-zFar),
-                         0, 0, -1.f, 0);
+    copy_matrix(mat, gGLLastProjection);
 }
 
-glh::matrix4f gl_lookat(LLVector3 eye, LLVector3 center, LLVector3 up)
+glm::vec3 mul_mat4_vec3(const glm::mat4& mat, const glm::vec3& vec)
 {
-    LLVector3 f = center-eye;
-    f.normVec();
-    up.normVec();
-    LLVector3 s = f % up;
-    LLVector3 u = s % f;
+    //const float w = vec[0] * mat[0][3] + vec[1] * mat[1][3] + vec[2] * mat[2][3] + mat[3][3];
+    //return glm::vec3(
+    //    (vec[0] * mat[0][0] + vec[1] * mat[1][0] + vec[2] * mat[2][0] + mat[3][0]) / w,
+    //    (vec[0] * mat[0][1] + vec[1] * mat[1][1] + vec[2] * mat[2][1] + mat[3][1]) / w,
+    //    (vec[0] * mat[0][2] + vec[1] * mat[1][2] + vec[2] * mat[2][2] + mat[3][2]) / w
+    //);
+    LLVector4a x, y, z, s, t, p, q;
+
+    x.splat(vec.x);
+    y.splat(vec.y);
+    z.splat(vec.z);
+
+    s.splat<3>(mat[0].data);
+    t.splat<3>(mat[1].data);
+    p.splat<3>(mat[2].data);
+    q.splat<3>(mat[3].data);
+
+    s.mul(x);
+    t.mul(y);
+    p.mul(z);
+    q.add(s);
+    t.add(p);
+    q.add(t);
 
-    return glh::matrix4f(s[0], s[1], s[2], 0,
-                      u[0], u[1], u[2], 0,
-                      -f[0], -f[1], -f[2], 0,
-                      0, 0, 0, 1);
+    x.mul(mat[0].data);
+    y.mul(mat[1].data);
+    z.mul(mat[2].data);
 
+    x.add(y);
+    z.add(mat[3].data);
+    LLVector4a res;
+    res.load3(glm::value_ptr(vec));
+    res.setAdd(x, z);
+    res.div(q);
+    return glm::make_vec3(res.getF32ptr());
 }
diff --git a/indra/llrender/llrender.h b/indra/llrender/llrender.h
index 39c13e328a..2645597b1a 100644
--- a/indra/llrender/llrender.h
+++ b/indra/llrender/llrender.h
@@ -42,7 +42,7 @@
 #include "llpointer.h"
 #include "llglheaders.h"
 #include "llmatrix4a.h"
-#include "glh/glh_linear.h"
+#include "glm/mat4x4.hpp"
 
 #include <array>
 #include <list>
@@ -401,8 +401,8 @@ public:
     void matrixMode(eMatrixMode mode);
     eMatrixMode getMatrixMode();
 
-    const glh::matrix4f& getModelviewMatrix();
-    const glh::matrix4f& getProjectionMatrix();
+    const glm::mat4& getModelviewMatrix();
+    const glm::mat4& getProjectionMatrix();
 
     void syncMatrices();
     void syncLightState();
@@ -502,7 +502,7 @@ private:
     eMatrixMode mMatrixMode;
     U32 mMatIdx[NUM_MATRIX_MODES];
     U32 mMatHash[NUM_MATRIX_MODES];
-    glh::matrix4f mMatrix[NUM_MATRIX_MODES][LL_MATRIX_STACK_DEPTH];
+    glm::mat4 mMatrix[NUM_MATRIX_MODES][LL_MATRIX_STACK_DEPTH];
     U32 mCurMatHash[NUM_MATRIX_MODES];
     U32 mLightHash;
     LLColor4 mAmbientLightColor;
@@ -536,8 +536,8 @@ extern F32 gGLLastModelView[16];
 extern F32 gGLLastProjection[16];
 extern F32 gGLProjection[16];
 extern S32 gGLViewport[4];
-extern F32 gGLDeltaModelView[16];
-extern F32 gGLInverseDeltaModelView[16];
+extern glm::mat4 gGLDeltaModelView;
+extern glm::mat4 gGLInverseDeltaModelView;
 
 extern thread_local LLRender gGL;
 
@@ -548,19 +548,20 @@ const F32 OGL_TO_CFR_ROTATION[16] = {  0.f,  0.f, -1.f,  0.f,   // -Z becomes X
                                        0.f,  1.f,  0.f,  0.f,   //  Y becomes Z
                                        0.f,  0.f,  0.f,  1.f };
 
-glh::matrix4f copy_matrix(F32* src);
-glh::matrix4f get_current_modelview();
-glh::matrix4f get_current_projection();
-glh::matrix4f get_last_modelview();
-glh::matrix4f get_last_projection();
+glm::mat4 copy_matrix(F32* src);
+glm::mat4 get_current_modelview();
+glm::mat4 get_current_projection();
+glm::mat4 get_last_modelview();
+glm::mat4 get_last_projection();
 
-void copy_matrix(const glh::matrix4f& src, F32* dst);
-void set_current_modelview(const glh::matrix4f& mat);
-void set_current_projection(glh::matrix4f& mat);
+void copy_matrix(const glm::mat4& src, F32* dst);
+void set_current_modelview(const glm::mat4& mat);
+void set_current_projection(const glm::mat4& mat);
+void set_last_modelview(const glm::mat4& mat);
+void set_last_projection(const glm::mat4& mat);
 
-glh::matrix4f gl_ortho(GLfloat left, GLfloat right, GLfloat bottom, GLfloat top, GLfloat znear, GLfloat zfar);
-glh::matrix4f gl_perspective(GLfloat fovy, GLfloat aspect, GLfloat zNear, GLfloat zFar);
-glh::matrix4f gl_lookat(LLVector3 eye, LLVector3 center, LLVector3 up);
+// glh compat
+glm::vec3 mul_mat4_vec3(const glm::mat4& mat, const glm::vec3& vec);
 
 #define LL_SHADER_LOADING_WARNS(...) LL_WARNS()
 
diff --git a/indra/llrender/llvertexbuffer.cpp b/indra/llrender/llvertexbuffer.cpp
index 666d792d1d..8524b470de 100644
--- a/indra/llrender/llvertexbuffer.cpp
+++ b/indra/llrender/llvertexbuffer.cpp
@@ -36,6 +36,7 @@
 #include "llshadermgr.h"
 #include "llglslshader.h"
 #include "llmemory.h"
+#include <glm/gtc/type_ptr.hpp>
 
 //Next Highest Power Of Two
 //helper function, returns first number > v that is a power of 2, or v if v is already a power of 2
@@ -590,13 +591,13 @@ void LLVertexBufferData::draw()
 
     gGL.matrixMode(LLRender::MM_MODELVIEW);
     gGL.pushMatrix();
-    gGL.loadMatrix(mModelView.m);
+    gGL.loadMatrix(glm::value_ptr(mModelView));
     gGL.matrixMode(LLRender::MM_PROJECTION);
     gGL.pushMatrix();
-    gGL.loadMatrix(mProjection.m);
+    gGL.loadMatrix(glm::value_ptr(mProjection));
     gGL.matrixMode(LLRender::MM_TEXTURE0);
     gGL.pushMatrix();
-    gGL.loadMatrix(mTexture0.m);
+    gGL.loadMatrix(glm::value_ptr(mTexture0));
 
     mVB->setBuffer();
 
diff --git a/indra/llrender/llvertexbuffer.h b/indra/llrender/llvertexbuffer.h
index 9fe468f89e..d4c6fbaf18 100644
--- a/indra/llrender/llvertexbuffer.h
+++ b/indra/llrender/llvertexbuffer.h
@@ -38,6 +38,7 @@
 #include <set>
 #include <vector>
 #include <list>
+#include <glm/gtc/matrix_transform.hpp>
 
 #define LL_MAX_VERTEX_ATTRIB_LOCATION 64
 
@@ -63,8 +64,11 @@ public:
         , mMode(0)
         , mCount(0)
         , mTexName(0)
+        , mProjection(glm::identity<glm::mat4>())
+        , mModelView(glm::identity<glm::mat4>())
+        , mTexture0(glm::identity<glm::mat4>())
     {}
-    LLVertexBufferData(LLVertexBuffer* buffer, U8 mode, U32 count, U32 tex_name, glh::matrix4f model_view, glh::matrix4f projection, glh::matrix4f texture0)
+    LLVertexBufferData(LLVertexBuffer* buffer, U8 mode, U32 count, U32 tex_name, const glm::mat4& model_view, const glm::mat4& projection, const glm::mat4& texture0)
         : mVB(buffer)
         , mMode(mode)
         , mCount(count)
@@ -78,9 +82,9 @@ public:
     U8 mMode;
     U32 mCount;
     U32 mTexName;
-    glh::matrix4f mProjection;
-    glh::matrix4f mModelView;
-    glh::matrix4f mTexture0;
+    glm::mat4 mProjection;
+    glm::mat4 mModelView;
+    glm::mat4 mTexture0;
 };
 typedef std::list<LLVertexBufferData> buffer_data_list_t;