Revert the depth_clamp extension patch.

Caused regression with the Re:Mobilize mod. See
#78.

Linux/sgml/Quakespasm.sgml

@@ -161,7 +161,6 @@ QuakeSpasm 0.94 has support for playing the 2021 re-release content: Copy the qu
 <item> Fix possible out-of-bound reads when handling progs type sizes.
 <item> Fix Dutch angle VP_PARALLEL_UPRIGHT sprites.
 <item> Fix an issue with lights blending by using 10 bit color depth for lightmaps. (For GLSL mode only.) Disable with "-nopackedpixels", if necessary.
-<item> Enable depth_clamp opengl extension if available. Fixes issues with water surface when going in and out of water in ej3_aesop. Disable with "-nodepthclamp", if necessary.
 <item> No relative motions when the window is not focused.
 <item> Status bar and intermission screen tweaks.
 <item> Properly display monster counts > 3 digits.

Quake/gl_vidsdl.c

@@ -97,7 +97,6 @@ modestate_t	modestate = MS_UNINIT;
 qboolean	scr_skipupdate;
 
 qboolean gl_mtexable = false;
-qboolean gl_nv_depth_clamp = false;
 qboolean gl_packed_pixels = false;
 qboolean gl_texture_env_combine = false; //johnfitz
 qboolean gl_texture_env_add = false; //johnfitz
@@ -1299,25 +1298,6 @@ static void GL_CheckExtensions (void)
 	}
 	#endif
 
-	// ARB_depth_clamp
-	//
-	if (COM_CheckParm("-nodepthclamp"))
-		Con_Warning ("depth_clamp disabled at command line\n");
-	else if (GL_ParseExtensionList(gl_extensions, "GL_ARB_depth_clamp"))
-	{
-		Con_Printf("FOUND: ARB_depth_clamp\n");
-		gl_nv_depth_clamp = true;
-	}
-	else if (GL_ParseExtensionList(gl_extensions, "GL_NV_depth_clamp"))
-	{
-		Con_Printf("FOUND: NV_depth_clamp\n");
-		gl_nv_depth_clamp = true;
-	}
-	else
-	{
-		Con_Warning ("depth_clamp not supported\n");
-	}
-
 	// glGenerateMipmap for warp textures
 	if (COM_CheckParm("-nowarpmipmaps"))
 		Con_Warning ("glGenerateMipmap disabled at command line\n");
@@ -1366,8 +1346,6 @@ static void GL_SetupState (void)
 	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 	glDepthRange (0, 1); //johnfitz -- moved here becuase gl_ztrick is gone.
 	glDepthFunc (GL_LEQUAL); //johnfitz -- moved here becuase gl_ztrick is gone.
-	if (gl_nv_depth_clamp)
-	    glEnable(GL_DEPTH_CLAMP_NV);
 }
 
 /*

Quake/glquake.h

@@ -259,11 +259,7 @@ void GL_PolygonOffset (int);
 #define GL_UNSIGNED_INT_10_10_10_2 0x8036
 #endif
 extern qboolean gl_packed_pixels;
-//GL_NV_depth_clamp
-#ifndef GL_DEPTH_CLAMP_NV
-#define GL_DEPTH_CLAMP_NV          0x864F
-#endif
-extern qboolean gl_nv_depth_clamp;
+
 //johnfitz -- GL_EXT_texture_env_combine
 //the values for GL_ARB_ are identical
 #define GL_COMBINE_EXT		0x8570

Quakespasm.html

@@ -235,7 +235,6 @@ <H2><A NAME="ss5.1">5.1</A> <A HREF="#toc5.1">Changes in 0.96.0</A>
 <LI> Fix possible out-of-bound reads when handling progs type sizes.</LI>
 <LI> Fix Dutch angle VP_PARALLEL_UPRIGHT sprites.</LI>
 <LI> Fix an issue with lights blending by using 10 bit color depth for lightmaps. (For GLSL mode only.) Disable with "-nopackedpixels", if necessary.</LI>
-<LI> Enable depth_clamp opengl extension if available. Fixes issues with water surface when going in and out of water in ej3_aesop. Disable with "-nodepthclamp", if necessary.</LI>
 <LI> No relative motions when the window is not focused.</LI>
 <LI> Status bar and intermission screen tweaks.</LI>
 <LI> Properly display monster counts &gt; 3 digits.</LI>

Quakespasm.txt

@@ -273,10 +273,6 @@
      lightmaps. (For GLSL mode only.) Disable with "-nopackedpixels",
      if necessary.
 
-  -  Enable depth_clamp opengl extension if available. Fixes issues
-     with water surface when going in and out of water in ej3_aesop.
-     Disable with "-nodepthclamp", if necessary.
-
   -  No relative motions when the window is not focused.
 
   -  Status bar and intermission screen tweaks.