From e274c62cfc4739f77ad46f6ad876ed0ea0b37385 Mon Sep 17 00:00:00 2001
From: Alibek Omarov <a1ba.omarov@gmail.com>
Date: Mon, 29 Jan 2024 05:44:14 +0300
Subject: [PATCH] ref: gl: use TextureFilteringEnabled to decide whether
 texture will have nearest filtering or linear

---
 ref/gl/gl_context.c | 24 ++++--------------------
 ref/gl/gl_image.c   | 28 +++++++++++++++++++++++++---
 ref/gl/gl_local.h   |  1 +
 3 files changed, 30 insertions(+), 23 deletions(-)

diff --git a/ref/gl/gl_context.c b/ref/gl/gl_context.c
index a5d9aa08..7d0d5682 100644
--- a/ref/gl/gl_context.c
+++ b/ref/gl/gl_context.c
@@ -167,25 +167,6 @@ static qboolean Mod_ProcessRenderData( model_t *mod, qboolean create, const byte
 	return loaded;
 }
 
-static qboolean R_TextureFilteringEnabled( int arg )
-{
-	gl_texture_t *glt;
-
-	if( arg < 0 )
-		return gl_texture_nearest.value == 0.0f;
-
-	glt = R_GetTexture( arg );
-
-	if( FBitSet( glt->flags, TF_NEAREST ))
-		return false;
-
-	// lightmaps have special cvar
-	if( FBitSet( glt->flags, TF_ATLAS_PAGE ))
-		return gl_lightmap_nearest.value == 0.0f;
-
-	return gl_texture_nearest.value == 0.0f;
-}
-
 static int GL_RefGetParm( int parm, int arg )
 {
 	gl_texture_t *glt;
@@ -257,7 +238,10 @@ static int GL_RefGetParm( int parm, int arg )
 	case PARM_SKY_SPHERE:
 		return FBitSet( tr.world->flags, FWORLD_SKYSPHERE ) && !FBitSet( tr.world->flags, FWORLD_CUSTOM_SKYBOX );
 	case PARM_TEX_FILTERING:
-		return R_TextureFilteringEnabled( arg );
+		if( arg < 0 )
+			return gl_texture_nearest.value == 0.0f;
+
+		return GL_TextureFilteringEnabled( R_GetTexture( arg ));
 	default:
 		return ENGINE_GET_PARM_( parm, arg );
 	}
diff --git a/ref/gl/gl_image.c b/ref/gl/gl_image.c
index 196b7ad8..5cdae89b 100644
--- a/ref/gl/gl_image.c
+++ b/ref/gl/gl_image.c
@@ -118,6 +118,28 @@ void GL_Bind( GLint tmu, GLenum texnum )
 	glState.currentTexturesIndex[tmu] = texnum;
 }
 
+qboolean GL_TextureFilteringEnabled( const gl_texture_t *tex )
+{
+	if( FBitSet( tex->flags, TF_NEAREST ))
+		return false;
+
+	if( FBitSet( tex->flags, TF_DEPTHMAP ))
+		return true;
+
+	if( FBitSet( tex->flags, TF_NOMIPMAP ) || tex->numMips <= 1 )
+	{
+		if( FBitSet( tex->flags, TF_ATLAS_PAGE ))
+			return gl_lightmap_nearest.value == 0.0f;
+
+		if( FBitSet( tex->flags, TF_SKYSIDE ))
+			return gl_texture_nearest.value == 0.0f;
+
+		return true;
+	}
+
+	return gl_texture_nearest.value == 0.0f;
+}
+
 /*
 =================
 GL_ApplyTextureParams
@@ -149,7 +171,7 @@ void GL_ApplyTextureParams( gl_texture_t *tex )
 			pglTexParameteri( tex->target, GL_DEPTH_TEXTURE_MODE_ARB, GL_LUMINANCE );
 		else pglTexParameteri( tex->target, GL_DEPTH_TEXTURE_MODE_ARB, GL_INTENSITY );
 
-		if( FBitSet( tex->flags, TF_NEAREST ))
+		if( !GL_TextureFilteringEnabled( tex ))
 		{
 			pglTexParameteri( tex->target, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
 			pglTexParameteri( tex->target, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
@@ -166,7 +188,7 @@ void GL_ApplyTextureParams( gl_texture_t *tex )
 	}
 	else if( FBitSet( tex->flags, TF_NOMIPMAP ) || tex->numMips <= 1 )
 	{
-		if( FBitSet( tex->flags, TF_NEAREST ) || ( IsLightMap( tex ) && gl_lightmap_nearest.value ) || ( tex->flags == TF_SKYSIDE && gl_texture_nearest.value ))
+		if( !GL_TextureFilteringEnabled( tex ))
 		{
 			pglTexParameteri( tex->target, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
 			pglTexParameteri( tex->target, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
@@ -179,7 +201,7 @@ void GL_ApplyTextureParams( gl_texture_t *tex )
 	}
 	else
 	{
-		if( FBitSet( tex->flags, TF_NEAREST ) || gl_texture_nearest.value )
+		if( !GL_TextureFilteringEnabled( tex ))
 		{
 			pglTexParameteri( tex->target, GL_TEXTURE_MIN_FILTER, GL_NEAREST_MIPMAP_NEAREST );
 			pglTexParameteri( tex->target, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
diff --git a/ref/gl/gl_local.h b/ref/gl/gl_local.h
index 11cccb2b..be29b8db 100644
--- a/ref/gl/gl_local.h
+++ b/ref/gl/gl_local.h
@@ -364,6 +364,7 @@ int GL_CreateTexture( const char *name, int width, int height, const void *buffe
 int GL_CreateTextureArray( const char *name, int width, int height, int depth, const void *buffer, texFlags_t flags );
 void GL_ProcessTexture( int texnum, float gamma, int topColor, int bottomColor );
 void GL_UpdateTexSize( int texnum, int width, int height, int depth );
+qboolean GL_TextureFilteringEnabled( const gl_texture_t *tex );
 void GL_ApplyTextureParams( gl_texture_t *tex );
 int GL_FindTexture( const char *name );
 void GL_FreeTexture( GLenum texnum );