Added some missing lines and made a few tweaks to allow Quake to run headless without crashing

engine/Quake/gl_draw.c

@@ -506,6 +506,9 @@ void Draw_Pic (int x, int y, qpic_t *pic)
 {
 	glpic_t			*gl;
 
+	if (!pic)
+		return;
+
 	if (scrap_dirty)
 		Scrap_Upload ();
 	gl = (glpic_t *)pic->data;

engine/UniQuake/stub/stub_vidgl.c

@@ -6,7 +6,7 @@ viddef_t vid;	// global video state
 modestate_t modestate = MS_UNINIT;
 
 int			gl_stencilbits = 0;
-qboolean	gl_texture_NPOT = false;
+qboolean	gl_texture_NPOT = true;	// No need to resample textures to power-of-two sizes
 qboolean	gl_glsl_gamma_able = false;
 qboolean	gl_mtexable = false;
 float		gl_max_anisotropy = 1;
@@ -22,12 +22,15 @@ void VID_Init(void)
 	Cvar_RegisterVariable(&vid_contrast);
 
 	memset(&vid, 0, sizeof(viddef_t));
-	vid.width = 1;
-	vid.height = 1;
-	vid.conwidth = 1;
-	vid.conheight = 1;
+	vid.width = 320;
+	vid.height = 200;
+	vid.conwidth = 320;
+	vid.conheight = 200;
 	vid.maxwarpwidth = 320;
 	vid.maxwarpheight = 200;
+
+	vid.colormap = host_colormap;
+	vid.fullbright = 256 - LittleLong(*((int *)vid.colormap + 2048));
 }
 
 void VID_Shutdown(void)