Expose all OpenGL filtering modes, use OpenGL names for them

Because of a review comment by numberZero.

include/SMaterialLayer.h

@@ -45,26 +45,28 @@ namespace video
 
 
 	//! Texture minification filter.
-	/** Used when scaling textures down. */
+	/** Used when scaling textures down. See the documentation on OpenGL's
+	`GL_TEXTURE_MIN_FILTER` for more information. */
 	enum E_TEXTURE_MIN_FILTER {
-		//! Nearest-neighbor interpolation.
+		//! Aka nearest-neighbor.
-		ETMINF_NEAREST = 0,
+		ETMINF_NEAREST_MIPMAP_NEAREST = 0,
-		//! Linear interpolation.
+		//! Aka bilinear.
-		ETMINF_BILINEAR,
+		ETMINF_LINEAR_MIPMAP_NEAREST,
-		//! Linear interpolation across mipmaps.
+		//! Isn't known by any other name.
-		/** Is equivalent to ETMINF_BILINEAR if mipmaps are disabled.
+		ETMINF_NEAREST_MIPMAP_LINEAR,
-		Only available as a minification filter since mipmaps are only used
+		//! Aka trilinear.
-		when scaling down. */
+		ETMINF_LINEAR_MIPMAP_LINEAR,
-		ETMINF_TRILINEAR,
 	};
 
 	//! Texture magnification filter.
-	/** Used when scaling textures up. */
+	/** Used when scaling textures up. See the documentation on OpenGL's
+	`GL_TEXTURE_MAG_FILTER` for more information.
+	Note that mipmaps are only used for minification, not for magnification. */
 	enum E_TEXTURE_MAG_FILTER {
-		//! Nearest-neighbor interpolation.
+		//! Aka nearest-neighbor.
 		ETMAGF_NEAREST = 0,
-		//! Linear interpolation.
+		//! Aka bilinear.
-		ETMAGF_BILINEAR,
+		ETMAGF_LINEAR,
 	};
 
 	//! Struct for holding material parameters which exist per texture layer
@@ -74,7 +76,7 @@ namespace video
 	public:
 		//! Default constructor
 		SMaterialLayer() : Texture(0), TextureWrapU(ETC_REPEAT), TextureWrapV(ETC_REPEAT), TextureWrapW(ETC_REPEAT),
-			MinFilter(ETMINF_BILINEAR), MagFilter(ETMAGF_BILINEAR), AnisotropicFilter(0), LODBias(0), TextureMatrix(0)
+			MinFilter(ETMINF_LINEAR_MIPMAP_NEAREST), MagFilter(ETMAGF_LINEAR), AnisotropicFilter(0), LODBias(0), TextureMatrix(0)
 		{
 		}
 
@@ -234,9 +236,9 @@ namespace video
 		//! to the three relevant boolean values found in the Minetest settings.
 		/** The value of `trilinear` takes precedence over the value of `bilinear`. */
 		void setFiltersMinetest(bool bilinear, bool trilinear, bool anisotropic) {
-			MinFilter = trilinear ? ETMINF_TRILINEAR :
+			MinFilter = trilinear ? ETMINF_LINEAR_MIPMAP_LINEAR :
-					(bilinear ? ETMINF_BILINEAR : ETMINF_NEAREST);
+					(bilinear ? ETMINF_LINEAR_MIPMAP_NEAREST : ETMINF_NEAREST_MIPMAP_NEAREST);
-			MagFilter = (trilinear || bilinear) ? ETMAGF_BILINEAR : ETMAGF_NEAREST;
+			MagFilter = (trilinear || bilinear) ? ETMAGF_LINEAR : ETMAGF_NEAREST;
 			AnisotropicFilter = anisotropic ? 0xFF : 0;
 		}
 

source/Irrlicht/CNullDriver.cpp

@@ -103,7 +103,7 @@ CNullDriver::CNullDriver(io::IFileSystem* io, const core::dimension2d<u32>& scre
 	InitMaterial2D.ZBuffer = video::ECFN_DISABLED;
 	InitMaterial2D.UseMipMaps = false;
 	InitMaterial2D.forEachTexture([] (auto &tex) {
-		tex.MinFilter = video::ETMINF_NEAREST;
+		tex.MinFilter = video::ETMINF_NEAREST_MIPMAP_NEAREST;
 		tex.MagFilter = video::ETMAGF_NEAREST;
 		tex.TextureWrapU = video::ETC_REPEAT;
 		tex.TextureWrapV = video::ETC_REPEAT;

source/Irrlicht/COGLES2Driver.cpp

@@ -4,6 +4,7 @@
 // For conditions of distribution and use, see copyright notice in Irrlicht.h
 
 #include "COGLES2Driver.h"
+#include <cassert>
 #include "CNullDriver.h"
 #include "IContextManager.h"
 
@@ -1700,7 +1701,8 @@ COGLES2Driver::~COGLES2Driver()
 			{
 				E_TEXTURE_MAG_FILTER magFilter = material.TextureLayers[i].MagFilter;
 				glTexParameteri(tmpTextureType, GL_TEXTURE_MAG_FILTER,
-					magFilter == ETMAGF_BILINEAR  ? GL_LINEAR : GL_NEAREST);
+					magFilter == ETMAGF_NEAREST ? GL_NEAREST :
+					(assert(magFilter == ETMAGF_LINEAR), GL_LINEAR));
 
 				tmpTexture->getStatesCache().MagFilter = magFilter;
 			}
@@ -1712,9 +1714,10 @@ COGLES2Driver::~COGLES2Driver()
 				{
 					E_TEXTURE_MIN_FILTER minFilter = material.TextureLayers[i].MinFilter;
 					glTexParameteri(tmpTextureType, GL_TEXTURE_MIN_FILTER,
-						minFilter == ETMINF_TRILINEAR ? GL_LINEAR_MIPMAP_LINEAR :
+						minFilter == ETMINF_NEAREST_MIPMAP_NEAREST ? GL_NEAREST_MIPMAP_NEAREST :
-						minFilter == ETMINF_BILINEAR ? GL_LINEAR_MIPMAP_NEAREST :
+						minFilter == ETMINF_LINEAR_MIPMAP_NEAREST ? GL_LINEAR_MIPMAP_NEAREST :
-						GL_NEAREST_MIPMAP_NEAREST);
+						minFilter == ETMINF_NEAREST_MIPMAP_LINEAR ? GL_NEAREST_MIPMAP_LINEAR :
+						(assert(minFilter == ETMINF_LINEAR_MIPMAP_LINEAR), GL_LINEAR_MIPMAP_LINEAR));
 
 					tmpTexture->getStatesCache().MinFilter = minFilter;
 					tmpTexture->getStatesCache().MipMapStatus = true;
@@ -1727,7 +1730,8 @@ COGLES2Driver::~COGLES2Driver()
 				{
 					E_TEXTURE_MIN_FILTER minFilter = material.TextureLayers[i].MinFilter;
 					glTexParameteri(tmpTextureType, GL_TEXTURE_MIN_FILTER,
-						(minFilter == ETMINF_TRILINEAR || minFilter == ETMINF_BILINEAR) ? GL_LINEAR : GL_NEAREST);
+						(minFilter == ETMINF_NEAREST_MIPMAP_NEAREST || minFilter == ETMINF_NEAREST_MIPMAP_LINEAR) ? GL_NEAREST :
+						(assert(minFilter == ETMINF_LINEAR_MIPMAP_NEAREST || minFilter == ETMINF_LINEAR_MIPMAP_LINEAR), GL_LINEAR));
 
 					tmpTexture->getStatesCache().MinFilter = minFilter;
 					tmpTexture->getStatesCache().MipMapStatus = false;

source/Irrlicht/COGLESDriver.cpp

@@ -3,6 +3,7 @@
 // For conditions of distribution and use, see copyright notice in irrlicht.h
 
 #include "COGLESDriver.h"
+#include <cassert>
 #include "CNullDriver.h"
 #include "IContextManager.h"
 
@@ -1918,7 +1919,8 @@ void COGLES1Driver::setTextureRenderStates(const SMaterial& material, bool reset
 		{
 			E_TEXTURE_MAG_FILTER magFilter = material.TextureLayers[i].MagFilter;
 			glTexParameteri(tmpTextureType, GL_TEXTURE_MAG_FILTER,
-				magFilter == ETMAGF_BILINEAR ? GL_LINEAR : GL_NEAREST);
+				magFilter == ETMAGF_NEAREST ? GL_NEAREST :
+				(assert(magFilter == ETMAGF_LINEAR), GL_LINEAR));
 
 			statesCache.MagFilter = magFilter;
 		}
@@ -1930,9 +1932,10 @@ void COGLES1Driver::setTextureRenderStates(const SMaterial& material, bool reset
 			{
 				E_TEXTURE_MIN_FILTER minFilter = material.TextureLayers[i].MinFilter;
 				glTexParameteri(tmpTextureType, GL_TEXTURE_MIN_FILTER,
-					minFilter == ETMINF_TRILINEAR ? GL_LINEAR_MIPMAP_LINEAR :
+					minFilter == ETMINF_NEAREST_MIPMAP_NEAREST ? GL_NEAREST_MIPMAP_NEAREST :
-					minFilter == ETMINF_BILINEAR ? GL_LINEAR_MIPMAP_NEAREST :
+					minFilter == ETMINF_LINEAR_MIPMAP_NEAREST ? GL_LINEAR_MIPMAP_NEAREST :
-					GL_NEAREST_MIPMAP_NEAREST);
+					minFilter == ETMINF_NEAREST_MIPMAP_LINEAR ? GL_NEAREST_MIPMAP_LINEAR :
+					(assert(minFilter == ETMINF_LINEAR_MIPMAP_LINEAR), GL_LINEAR_MIPMAP_LINEAR));
 
 				statesCache.MinFilter = minFilter;
 				statesCache.MipMapStatus = true;
@@ -1945,7 +1948,9 @@ void COGLES1Driver::setTextureRenderStates(const SMaterial& material, bool reset
 			{
 				E_TEXTURE_MIN_FILTER minFilter = material.TextureLayers[i].MinFilter;
 				glTexParameteri(tmpTextureType, GL_TEXTURE_MIN_FILTER,
-					(minFilter == ETMINF_TRILINEAR || minFilter == ETMINF_BILINEAR) ? GL_LINEAR : GL_NEAREST);
+					(minFilter == ETMINF_NEAREST_MIPMAP_NEAREST || minFilter == ETMINF_NEAREST_MIPMAP_LINEAR) ? GL_NEAREST :
+					(assert(minFilter == ETMINF_LINEAR_MIPMAP_NEAREST || minFilter == ETMINF_LINEAR_MIPMAP_LINEAR), GL_LINEAR));
+
 
 				statesCache.MinFilter = minFilter;
 				statesCache.MipMapStatus = false;

source/Irrlicht/COpenGLCoreTexture.h

@@ -31,7 +31,7 @@ public:
 	struct SStatesCache
 	{
 		SStatesCache() : WrapU(ETC_REPEAT), WrapV(ETC_REPEAT), WrapW(ETC_REPEAT),
-			LODBias(0), AnisotropicFilter(0), MinFilter(video::ETMINF_NEAREST),
+			LODBias(0), AnisotropicFilter(0), MinFilter(video::ETMINF_NEAREST_MIPMAP_NEAREST),
 			MagFilter(video::ETMAGF_NEAREST), MipMapStatus(false), IsCached(false)
 		{
 		}

source/Irrlicht/COpenGLDriver.cpp

@@ -3,6 +3,7 @@
 // For conditions of distribution and use, see copyright notice in irrlicht.h
 
 #include "COpenGLDriver.h"
+#include <cassert>
 #include "CNullDriver.h"
 #include "IContextManager.h"
 
@@ -2713,7 +2714,8 @@ void COpenGLDriver::setTextureRenderStates(const SMaterial& material, bool reset
 			{
 				E_TEXTURE_MAG_FILTER magFilter = material.TextureLayers[i].MagFilter;
 				glTexParameteri(tmpType, GL_TEXTURE_MAG_FILTER,
-					magFilter == ETMAGF_BILINEAR ? GL_LINEAR : GL_NEAREST);
+					magFilter == ETMAGF_NEAREST ? GL_NEAREST :
+					(assert(magFilter == ETMAGF_LINEAR), GL_LINEAR));
 
 				statesCache.MagFilter = magFilter;
 			}
@@ -2725,9 +2727,10 @@ void COpenGLDriver::setTextureRenderStates(const SMaterial& material, bool reset
 				{
 					E_TEXTURE_MIN_FILTER minFilter = material.TextureLayers[i].MinFilter;
 					glTexParameteri(tmpType, GL_TEXTURE_MIN_FILTER,
-						minFilter == ETMINF_TRILINEAR ? GL_LINEAR_MIPMAP_LINEAR :
+						minFilter == ETMINF_NEAREST_MIPMAP_NEAREST ? GL_NEAREST_MIPMAP_NEAREST :
-						minFilter == ETMINF_BILINEAR ? GL_LINEAR_MIPMAP_NEAREST :
+						minFilter == ETMINF_LINEAR_MIPMAP_NEAREST ? GL_LINEAR_MIPMAP_NEAREST :
-						GL_NEAREST_MIPMAP_NEAREST);
+						minFilter == ETMINF_NEAREST_MIPMAP_LINEAR ? GL_NEAREST_MIPMAP_LINEAR :
+						(assert(minFilter == ETMINF_LINEAR_MIPMAP_LINEAR), GL_LINEAR_MIPMAP_LINEAR));
 
 					statesCache.MinFilter = minFilter;
 					statesCache.MipMapStatus = true;
@@ -2740,7 +2743,8 @@ void COpenGLDriver::setTextureRenderStates(const SMaterial& material, bool reset
 				{
 					E_TEXTURE_MIN_FILTER minFilter = material.TextureLayers[i].MinFilter;
 					glTexParameteri(tmpType, GL_TEXTURE_MIN_FILTER,
-						(minFilter == ETMINF_TRILINEAR || minFilter == ETMINF_BILINEAR) ? GL_LINEAR : GL_NEAREST);
+						(minFilter == ETMINF_NEAREST_MIPMAP_NEAREST || minFilter == ETMINF_NEAREST_MIPMAP_LINEAR) ? GL_NEAREST :
+						(assert(minFilter == ETMINF_LINEAR_MIPMAP_NEAREST || minFilter == ETMINF_LINEAR_MIPMAP_LINEAR), GL_LINEAR));
 
 					statesCache.MinFilter = minFilter;
 					statesCache.MipMapStatus = false;

source/Irrlicht/OpenGL/Driver.cpp

@@ -1460,7 +1460,8 @@ COpenGL3DriverBase::~COpenGL3DriverBase()
 			{
 				E_TEXTURE_MAG_FILTER magFilter = material.TextureLayers[i].MagFilter;
 				glTexParameteri(tmpTextureType, GL_TEXTURE_MAG_FILTER,
-					magFilter == ETMAGF_BILINEAR  ? GL_LINEAR : GL_NEAREST);
+					magFilter == ETMAGF_NEAREST ? GL_NEAREST :
+					(assert(magFilter == ETMAGF_LINEAR), GL_LINEAR));
 
 				tmpTexture->getStatesCache().MagFilter = magFilter;
 			}
@@ -1472,9 +1473,10 @@ COpenGL3DriverBase::~COpenGL3DriverBase()
 				{
 					E_TEXTURE_MIN_FILTER minFilter = material.TextureLayers[i].MinFilter;
 					glTexParameteri(tmpTextureType, GL_TEXTURE_MIN_FILTER,
-						minFilter == ETMINF_TRILINEAR ? GL_LINEAR_MIPMAP_LINEAR :
+						minFilter == ETMINF_NEAREST_MIPMAP_NEAREST ? GL_NEAREST_MIPMAP_NEAREST :
-						minFilter == ETMINF_BILINEAR ? GL_LINEAR_MIPMAP_NEAREST :
+						minFilter == ETMINF_LINEAR_MIPMAP_NEAREST ? GL_LINEAR_MIPMAP_NEAREST :
-						GL_NEAREST_MIPMAP_NEAREST);
+						minFilter == ETMINF_NEAREST_MIPMAP_LINEAR ? GL_NEAREST_MIPMAP_LINEAR :
+						(assert(minFilter == ETMINF_LINEAR_MIPMAP_LINEAR), GL_LINEAR_MIPMAP_LINEAR));
 
 					tmpTexture->getStatesCache().MinFilter = minFilter;
 					tmpTexture->getStatesCache().MipMapStatus = true;
@@ -1487,7 +1489,8 @@ COpenGL3DriverBase::~COpenGL3DriverBase()
 				{
 					E_TEXTURE_MIN_FILTER minFilter = material.TextureLayers[i].MinFilter;
 					glTexParameteri(tmpTextureType, GL_TEXTURE_MIN_FILTER,
-						(minFilter == ETMINF_TRILINEAR || minFilter == ETMINF_BILINEAR) ? GL_LINEAR : GL_NEAREST);
+						(minFilter == ETMINF_NEAREST_MIPMAP_NEAREST || minFilter == ETMINF_NEAREST_MIPMAP_LINEAR) ? GL_NEAREST :
+						(assert(minFilter == ETMINF_LINEAR_MIPMAP_NEAREST || minFilter == ETMINF_LINEAR_MIPMAP_LINEAR), GL_LINEAR));
 
 					tmpTexture->getStatesCache().MinFilter = minFilter;
 					tmpTexture->getStatesCache().MipMapStatus = false;