Committing patch #25676 Anisotropic filtering in viewport and BGE by me.

This patch adds anisotropic filtering of textures in the viewport and the BGE. The quality of the filtering is adjustable in the user preferences under System. For more information on anisotropic filtering:
http://en.wikipedia.org/wiki/Anisotropic_filtering

One current limitation of this setup (having the option a user preference) is it makes runtimes more troublesome. Runtimes don't have user preferences set, so for now the blender player defaults to 2x AF. Options will be added later to change this value (probably a command line option).

release/scripts/startup/bl_ui/space_userpref.py

@@ -438,6 +438,8 @@ class USERPREF_PT_system(bpy.types.Panel):
         col.label(text="OpenGL:")
         col.prop(system, "gl_clip_alpha", slider=True)
         col.prop(system, "use_mipmaps")
+        col.label(text="Anisotropic Filtering")
+        col.prop(system, "anisotropic_filter", text="")
         col.prop(system, "use_vertex_buffer_objects")
         #Anti-aliasing is disabled as it breaks broder/lasso select
         #col.prop(system, "use_antialiasing")

source/blender/editors/interface/resources.c

@@ -1580,6 +1580,8 @@ void init_userdef_do_versions(void)
 		U.dragthreshold= 5;
 	if (U.widget_unit==0)
 		U.widget_unit= (U.dpi * 20 + 36)/72;
+	if (U.anisotropic_filter <= 0)
+		U.anisotropic_filter = 1;
 
 	/* funny name, but it is GE stuff, moves userdef stuff to engine */
 // XXX	space_set_commmandline_options();

source/blender/gpu/GPU_draw.h

@@ -112,6 +112,11 @@ void GPU_set_mipmap(int mipmap);
 void GPU_set_linear_mipmap(int linear);
 void GPU_paint_set_mipmap(int mipmap);
 
+/* Anisotropic filtering settings
+ * - these will free textures on changes */
+void GPU_set_anisotropic(float value);
+float GPU_get_anisotropic(void);
+
 /* Image updates and free
  * - these deal with images bound as opengl textures */
 

source/blender/gpu/intern/gpu_draw.c

@@ -246,8 +246,9 @@ static struct GPUTextureState {
 	int domipmap, linearmipmap;
 
 	int alphamode;
+	float anisotropic;
 	MTFace *lasttface;
-} GTS = {0, 0, 0, 0, 0, 0, 0, 0, NULL, NULL, 1, 0, -1, NULL};
+} GTS = {0, 0, 0, 0, 0, 0, 0, 0, NULL, NULL, 1, 0, -1, 1.f, NULL};
 
 /* Mipmap settings */
 
@@ -292,6 +293,26 @@ static GLenum gpu_get_mipmap_filter(int mag)
 	}
 }
 
+/* Anisotropic filtering settings */
+void GPU_set_anisotropic(float value)
+{
+	if (GTS.anisotropic != value)
+	{
+		GPU_free_images();
+
+		/* Clamp value to the maximum value the graphics card supports */
+		if (value > GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT)
+			value = GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT;
+
+		GTS.anisotropic = value;
+	}
+}
+
+float GPU_get_anisotropic()
+{
+	return GTS.anisotropic;
+}
+
 /* Set OpenGL state for an MTFace */
 
 static void gpu_make_repbind(Image *ima)
@@ -559,6 +580,8 @@ int GPU_verify_image(Image *ima, ImageUser *iuser, int tftile, int compare, int
 		ima->tpageflag |= IMA_MIPMAP_COMPLETE;
 	}
 
+	if (GLEW_EXT_texture_filter_anisotropic)
+		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAX_ANISOTROPY_EXT, GPU_get_anisotropic());
 	/* set to modulate with vertex color */
 	glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
 		

source/blender/makesdna/DNA_userdef_types.h

@@ -375,7 +375,7 @@ typedef struct UserDef {
 	short scrcastwait;		/* milliseconds between screencast snapshots */
 	
 	short widget_unit;		/* defaults to 20 for 72 DPI setting */
-	short pad[3];			
+	short anisotropic_filter;
 
 	char versemaster[160];
 	char verseuser[160];
@@ -385,7 +385,6 @@ typedef struct UserDef {
 	short autokey_flag;		/* flags for autokeying */
 	
 	short text_render, pad9;		/*options for text rendering*/
-	float pad10;
 
 	struct ColorBand coba_weight;	/* from texture.h */
 

source/blender/makesrna/intern/rna_userdef.c

@@ -117,6 +117,12 @@ static void rna_userdef_mipmap_update(Main *bmain, Scene *scene, PointerRNA *ptr
 	rna_userdef_update(bmain, scene, ptr);
 }
 
+static void rna_userdef_anisotropic_update(Main *bmain, Scene *scene, PointerRNA *ptr)
+{
+	GPU_set_anisotropic(U.anisotropic_filter);
+	rna_userdef_update(bmain, scene, ptr);
+}
+
 static void rna_userdef_gl_texture_limit_update(Main *bmain, Scene *scene, PointerRNA *ptr)
 {
 	GPU_free_images();
@@ -2346,6 +2352,14 @@ static void rna_def_userdef_system(BlenderRNA *brna)
 		{128, "CLAMP_128", 0, "128", ""},
 		{0, NULL, 0, NULL, NULL}};
 
+	static EnumPropertyItem anisotropic_items[]  ={
+		{1, "FILTER_0", 0, "Off", ""},
+		{2, "FILTER_2", 0, "2x", ""},
+		{4, "FILTER_4", 0, "4x", ""},
+		{8, "FILTER_8", 0, "8x", ""},
+		{16, "FILTER_16", 0, "16x", ""},
+		{0, NULL, 0, NULL, NULL}};
+
 	static EnumPropertyItem audio_mixing_samples_items[] = {
 		{256, "SAMPLES_256", 0, "256", "Set audio mixing buffer size to 256 samples"},
 		{512, "SAMPLES_512", 0, "512", "Set audio mixing buffer size to 512 samples"},
@@ -2568,6 +2582,13 @@ static void rna_def_userdef_system(BlenderRNA *brna)
 	prop= RNA_def_property(srna, "use_antialiasing", PROP_BOOLEAN, PROP_NONE);
 	RNA_def_property_boolean_negative_sdna(prop, NULL, "gameflags", USER_DISABLE_AA);
 	RNA_def_property_ui_text(prop, "Anti-aliasing", "Use anti-aliasing for the 3D view (may impact redraw performance)");
+
+	prop= RNA_def_property(srna, "anisotropic_filter", PROP_ENUM, PROP_NONE);
+	RNA_def_property_enum_sdna(prop, NULL, "anisotropic_filter");
+	RNA_def_property_enum_items(prop, anisotropic_items);
+	RNA_def_property_enum_default(prop, 1);
+	RNA_def_property_ui_text(prop, "Anisotropic Filter", "The quality of the anisotropic filtering (values greater than 1.0 enable anisotropic filtering)");
+	RNA_def_property_update(prop, 0, "rna_userdef_anisotropic_update");
 	
 	prop= RNA_def_property(srna, "gl_texture_limit", PROP_ENUM, PROP_NONE);
 	RNA_def_property_enum_sdna(prop, NULL, "glreslimit");

source/blender/windowmanager/intern/wm_init_exit.c

@@ -169,6 +169,7 @@ void WM_init(bContext *C, int argc, const char **argv)
 	if (!G.background) {
 		GPU_extensions_init();
 		GPU_set_mipmap(!(U.gameflags & USER_DISABLE_MIPMAP));
+		GPU_set_anisotropic(U.anisotropic_filter);
 	
 		UI_init();
 	}

source/gameengine/GamePlayer/ghost/GPG_ghost.cpp

@@ -450,6 +450,9 @@ int main(int argc, char** argv)
 	U.audioformat = 0x24;
 	U.audiochannels = 2;
 
+	// XXX this one too
+	U.anisotropic_filter = 2;
+
 	sound_init_once();
 
 	/* if running blenderplayer the last argument can't be parsed since it has to be the filename. */
@@ -705,6 +708,8 @@ int main(int argc, char** argv)
 		{
 			GPU_set_mipmap(0);
 		}
+
+		GPU_set_anisotropic(U.anisotropic_filter);
 		
 		// Create the system
 		if (GHOST_ISystem::createSystem() == GHOST_kSuccess)

source/gameengine/Ketsji/BL_Texture.cpp

@@ -28,6 +28,7 @@
 #define spit(x) std::cout << x << std::endl;
 
 #include "MEM_guardedalloc.h"
+#include "GPU_draw.h"
 
 extern "C" {
 	// envmaps
@@ -175,6 +176,8 @@ void BL_Texture::InitGLTex(unsigned int *pix,int x,int y,bool mipmap)
 		glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, x, y, 0, GL_RGBA, GL_UNSIGNED_BYTE, pix );
 	}
 
+	if (GLEW_EXT_texture_filter_anisotropic)
+		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAX_ANISOTROPY_EXT, GPU_get_anisotropic());
 	glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
 }
 
@@ -199,6 +202,9 @@ void BL_Texture::InitNonPow2Tex(unsigned int *pix,int x,int y,bool mipmap)
 		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 		glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, nx, ny, 0, GL_RGBA, GL_UNSIGNED_BYTE, newPixels );
 	}
+
+	if (GLEW_EXT_texture_filter_anisotropic)
+		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAX_ANISOTROPY_EXT, GPU_get_anisotropic());
 	glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
 	free(newPixels);
 }