diff --git a/src/gl/compatibility/gl_20.cpp b/src/gl/compatibility/gl_20.cpp
index 280affa1a..b06ce762b 100644
--- a/src/gl/compatibility/gl_20.cpp
+++ b/src/gl/compatibility/gl_20.cpp
@@ -143,12 +143,15 @@ BYTE *gl_WarpBuffer(BYTE *buffer, int Width, int Height, int warp, float Speed)
 	int xmask = xsize - 1;
 	int ymask = ysize - 1;
 	int ds_xbits;
-	int i, x;
+	int i;
 
 	if (warp == 1)
 	{
 		for (ds_xbits = -1, i = Width; i; i >>= 1, ds_xbits++);
 
+		// pending consolidation with the software renderer's code.
+
+		/*
 		for (x = xsize - 1; x >= 0; x--)
 		{
 			int yt, yf = (finesine[(timebase + (x + 17) * 128)&FINEMASK] >> 13) & ymask;
@@ -172,12 +175,14 @@ BYTE *gl_WarpBuffer(BYTE *buffer, int Width, int Height, int warp, float Speed)
 			}
 			memcpy(out + y*xsize, linebuffer, xsize * sizeof(DWORD));
 		}
+		*/
 	}
 	else
 	{
 		int ybits;
 		for (ybits = -1, i = ysize; i; i >>= 1, ybits++);
 
+		/*
 		DWORD timebase = (r_FrameTime * Speed * 40 / 28);
 		for (x = xsize - 1; x >= 0; x--)
 		{
@@ -194,6 +199,7 @@ BYTE *gl_WarpBuffer(BYTE *buffer, int Width, int Height, int warp, float Speed)
 				*dest = *source;
 			}
 		}
+		*/
 	}
 	delete[] buffer;
 	return (BYTE*)out;
diff --git a/src/gl/data/gl_data.cpp b/src/gl/data/gl_data.cpp
index ba6105d5a..2aea2b8a3 100644
--- a/src/gl/data/gl_data.cpp
+++ b/src/gl/data/gl_data.cpp
@@ -431,11 +431,11 @@ FTextureID gl_GetSpriteFrame(unsigned sprite, int frame, int rot, angle_t ang, b
 		{
 			if (sprframe->Texture[0] == sprframe->Texture[1])
 			{
-				rot = (ang + (angle_t)(ANGLE_45/2)*9) >> 28;
+				rot = (ang + (angle_t)(ANGLE_90/4)*9) >> 28;
 			}
 			else
 			{
-				rot = (ang + (angle_t)(ANGLE_45/2)*9-(angle_t)(ANGLE_180/16)) >> 28;
+				rot = (ang + (angle_t)(ANGLE_90/4)*9-(angle_t)(ANGLE_180/16)) >> 28;
 			}
 		}
 		if (mirror) *mirror = !!(sprframe->Flip&(1<<rot));
diff --git a/src/gl/models/gl_models_md2.cpp b/src/gl/models/gl_models_md2.cpp
index c40e20d90..7a27e12dc 100644
--- a/src/gl/models/gl_models_md2.cpp
+++ b/src/gl/models/gl_models_md2.cpp
@@ -64,8 +64,8 @@ static float   avertexnormals[NUMVERTEXNORMALS][3] = {
 
 static void UnpackVector(unsigned short packed, float vec[3])
 {
-	float   yaw = (packed & 511) / 512.0f * 2 * PI;
-	float   pitch = ((packed >> 9) / 127.0f - 0.5f) * PI;
+	float   yaw = (packed & 511) / 512.0f * 2 * M_PI;
+	float   pitch = ((packed >> 9) / 127.0f - 0.5f) * M_PI;
 	float   cosp = (float) cos(pitch);
 
 	vec[VX] = (float) cos(yaw) * cosp;
diff --git a/src/gl/models/gl_models_md3.cpp b/src/gl/models/gl_models_md3.cpp
index 13f02bc0a..7e8a4845e 100644
--- a/src/gl/models/gl_models_md3.cpp
+++ b/src/gl/models/gl_models_md3.cpp
@@ -60,8 +60,8 @@ static void UnpackVector(unsigned short packed, float & nx, float & ny, float &
 {
 	double lat = ( packed >> 8 ) & 0xff;
 	double lng = ( packed & 0xff );
-	lat *= PI/128;
-	lng *= PI/128;
+	lat *= M_PI/128;
+	lng *= M_PI/128;
 
 	nx = cos(lat) * sin(lng);
 	ny = sin(lat) * sin(lng);
diff --git a/src/gl/scene/gl_clipper.h b/src/gl/scene/gl_clipper.h
index 7d05cf701..977107e61 100644
--- a/src/gl/scene/gl_clipper.h
+++ b/src/gl/scene/gl_clipper.h
@@ -2,7 +2,6 @@
 #define __GL_CLIPPER
 
 #include "doomtype.h"
-#include "tables.h"
 #include "xs_Float.h"
 #include "r_utility.h"
 
diff --git a/src/gl/scene/gl_drawinfo.h b/src/gl/scene/gl_drawinfo.h
index 9745ade88..744ffeef4 100644
--- a/src/gl/scene/gl_drawinfo.h
+++ b/src/gl/scene/gl_drawinfo.h
@@ -229,7 +229,7 @@ struct FDrawInfo
 
 	FDrawInfo * next;
 	GLDrawList drawlists[GLDL_TYPES];
-	GLDrawList *dldrawlists;	// only gets allocated when needed.
+	GLDrawList *dldrawlists = NULL;	// only gets allocated when needed.
 
 	FDrawInfo();
 	~FDrawInfo();
diff --git a/src/gl/scene/gl_scene.cpp b/src/gl/scene/gl_scene.cpp
index a745f7307..f09343f44 100644
--- a/src/gl/scene/gl_scene.cpp
+++ b/src/gl/scene/gl_scene.cpp
@@ -793,7 +793,7 @@ sector_t * FGLRenderer::RenderViewpoint (AActor * camera, GL_IRECT * bounds, flo
 	SetViewArea();
 
 	// We have to scale the pitch to account for the pixel stretching, because the playsim doesn't know about this and treats it as 1:1.
-	double radPitch = clamp(ViewPitch.Normalized180().Radians(), -PI / 2, PI / 2);
+	double radPitch = ViewPitch.Normalized180().Radians();
 	double angx = cos(radPitch);
 	double angy = sin(radPitch) * glset.pixelstretch;
 	double alen = sqrt(angx*angx + angy*angy);
@@ -922,7 +922,7 @@ void FGLRenderer::RenderView (player_t* player)
 	TThinkerIterator<ADynamicLight> it(STAT_DLIGHT);
 	GLRenderer->mLightCount = ((it.Next()) != NULL);
 
-	sector_t * viewsector = RenderViewpoint(player->camera, NULL, FieldOfView * 360.0f / FINEANGLES, ratio, fovratio, true, true);
+	sector_t * viewsector = RenderViewpoint(player->camera, NULL, FieldOfView.Degrees, ratio, fovratio, true, true);
 
 	All.Unclock();
 }
@@ -952,7 +952,7 @@ void FGLRenderer::WriteSavePic (player_t *player, FILE *file, int width, int hei
 	GLRenderer->mLightCount = ((it.Next()) != NULL);
 
 	sector_t *viewsector = RenderViewpoint(players[consoleplayer].camera, &bounds, 
-								FieldOfView * 360.0f / FINEANGLES, 1.6f, 1.6f, true, false);
+								FieldOfView.Degrees, 1.6f, 1.6f, true, false);
 	glDisable(GL_STENCIL_TEST);
 	gl_RenderState.SetFixedColormap(CM_DEFAULT);
 	gl_RenderState.SetSoftLightLevel(-1);