From 1a5c42810009e072fd06773b812535591682bc98 Mon Sep 17 00:00:00 2001
From: Eric Wasylishen <ewasylishen@gmail.com>
Date: Mon, 26 Jan 2015 20:18:39 +0000
Subject: [PATCH] VID_Restart: delete all GL textures before calling
 VID_SetMode. SDL2 reuses the gl context when changing modes, so the
 TexMgr_ReloadImages call after the mode change was leaking textures.

git-svn-id: svn://svn.code.sf.net/p/quakespasm/code/trunk/quakespasm@1156 af15c1b1-3010-417e-b628-4374ebc0bcbd
---
 Quake/gl_texmgr.c | 41 +++++++++++++++++++++++++++++++++++++++--
 Quake/gl_texmgr.h |  1 +
 Quake/gl_vidsdl.c |  7 +++++++
 3 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/Quake/gl_texmgr.c b/Quake/gl_texmgr.c
index 492c037b..f92af8cb 100644
--- a/Quake/gl_texmgr.c
+++ b/Quake/gl_texmgr.c
@@ -341,6 +341,8 @@ gltexture_t *TexMgr_NewTexture (void)
 	return glt;
 }
 
+static void GL_DeleteTexture (gltexture_t *texture);
+
 /*
 ================
 TexMgr_FreeTexture
@@ -362,7 +364,7 @@ void TexMgr_FreeTexture (gltexture_t *kill)
 		kill->next = free_gltextures;
 		free_gltextures = kill;
 
-		glDeleteTextures(1, &kill->texnum);
+		GL_DeleteTexture(kill);
 		numgltextures--;
 		return;
 	}
@@ -375,7 +377,7 @@ void TexMgr_FreeTexture (gltexture_t *kill)
 			kill->next = free_gltextures;
 			free_gltextures = kill;
 
-			glDeleteTextures(1, &kill->texnum);
+			GL_DeleteTexture(kill);
 			numgltextures--;
 			return;
 		}
@@ -420,6 +422,21 @@ void TexMgr_FreeTexturesForOwner (qmodel_t *owner)
 	}
 }
 
+/*
+================
+TexMgr_DeleteTextureObjects
+================
+*/
+void TexMgr_DeleteTextureObjects (void)
+{
+	gltexture_t *glt;
+
+	for (glt = active_gltextures; glt; glt = glt->next)
+	{
+		GL_DeleteTexture (glt);
+	}
+}
+
 /*
 ================================================================================
 
@@ -1466,3 +1483,23 @@ void GL_Bind (gltexture_t *texture)
 		texture->visframe = r_framecount;
 	}
 }
+
+/*
+================
+GL_DeleteTexture -- ericw
+
+Wrapper around glDeleteTextures that also updates our cached current texture
+binding, if necessary.
+================
+*/
+static void GL_DeleteTexture (gltexture_t *texture)
+{
+	glDeleteTextures (1, &texture->texnum);
+
+	if (texture->texnum == currenttexture[currenttarget - GL_TEXTURE0_ARB])
+	{
+		currenttexture[currenttarget - GL_TEXTURE0_ARB] = 0;
+	}
+
+	texture->texnum = 0;
+}
diff --git a/Quake/gl_texmgr.h b/Quake/gl_texmgr.h
index 472d7342..f772df30 100644
--- a/Quake/gl_texmgr.h
+++ b/Quake/gl_texmgr.h
@@ -85,6 +85,7 @@ void TexMgr_FreeTextures (unsigned int flags, unsigned int mask);
 void TexMgr_FreeTexturesForOwner (qmodel_t *owner);
 void TexMgr_NewGame (void);
 void TexMgr_Init (void);
+void TexMgr_DeleteTextureObjects (void);
 
 // IMAGE LOADING
 gltexture_t *TexMgr_LoadImage (qmodel_t *owner, const char *name, int width, int height, enum srcformat format,
diff --git a/Quake/gl_vidsdl.c b/Quake/gl_vidsdl.c
index 37627cdd..c0c7ff4e 100644
--- a/Quake/gl_vidsdl.c
+++ b/Quake/gl_vidsdl.c
@@ -676,6 +676,13 @@ static void VID_Restart (void)
 				width, height, bpp, fullscreen? "fullscreen" : "windowed");
 		return;
 	}
+	
+// ericw -- depending on platform / SDL version, after a video mode change we
+// can have a new context (all textures are already freed) or the same context
+// as before, in which case we need to delete the old textures to avoid a
+// memory leak.
+
+	TexMgr_DeleteTextureObjects ();
 
 //
 // set new mode