From 97b1f1d97b685155e279d9d02d7c6343ef233ae8 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 18 Sep 2021 15:40:30 +0300
Subject: [PATCH] Make the sampler-related enums independent of OpenGL
 constants

---
 source/core/sampler.cpp | 36 +++++++++++++++++++++++++++++++-----
 source/core/sampler.h   | 22 ++++++++++++----------
 2 files changed, 43 insertions(+), 15 deletions(-)

diff --git a/source/core/sampler.cpp b/source/core/sampler.cpp
index c810789b..45db2980 100644
--- a/source/core/sampler.cpp
+++ b/source/core/sampler.cpp
@@ -36,17 +36,17 @@ Sampler::Sampler():
 void Sampler::update() const
 {
 	if(dirty_params&MIN_FILTER)
-		glSamplerParameteri(id, GL_TEXTURE_MIN_FILTER, min_filter);
+		glSamplerParameteri(id, GL_TEXTURE_MIN_FILTER, get_gl_filter(min_filter));
 	if(dirty_params&MAG_FILTER)
-		glSamplerParameteri(id, GL_TEXTURE_MAG_FILTER, mag_filter);
+		glSamplerParameteri(id, GL_TEXTURE_MAG_FILTER, get_gl_filter(mag_filter));
 	if(dirty_params&MAX_ANISOTROPY)
 		glSamplerParameterf(id, GL_TEXTURE_MAX_ANISOTROPY_EXT, max_anisotropy);
 	if(dirty_params&WRAP_S)
-		glSamplerParameteri(id, GL_TEXTURE_WRAP_S, wrap_s);
+		glSamplerParameteri(id, GL_TEXTURE_WRAP_S, get_gl_wrap(wrap_s));
 	if(dirty_params&WRAP_T)
-		glSamplerParameteri(id, GL_TEXTURE_WRAP_T, wrap_t);
+		glSamplerParameteri(id, GL_TEXTURE_WRAP_T, get_gl_wrap(wrap_t));
 	if(dirty_params&WRAP_R)
-		glSamplerParameteri(id, GL_TEXTURE_WRAP_R, wrap_r);
+		glSamplerParameteri(id, GL_TEXTURE_WRAP_R, get_gl_wrap(wrap_r));
 	if(dirty_params&BORDER_COLOR)
 		glSamplerParameterfv(id, GL_TEXTURE_BORDER_COLOR, &border_color.r);
 	if(dirty_params&COMPARE)
@@ -218,6 +218,32 @@ bool is_mipmapped(TextureFilter filter)
 		filter==LINEAR_MIPMAP_NEAREST || filter==LINEAR_MIPMAP_LINEAR);
 }
 
+GLenum get_gl_filter(TextureFilter filter)
+{
+	switch(filter)
+	{
+	case NEAREST: return GL_NEAREST;
+	case LINEAR: return GL_LINEAR;
+	case NEAREST_MIPMAP_NEAREST: return GL_NEAREST_MIPMAP_NEAREST;
+	case NEAREST_MIPMAP_LINEAR: return GL_NEAREST_MIPMAP_LINEAR;
+	case LINEAR_MIPMAP_NEAREST: return GL_LINEAR_MIPMAP_NEAREST;
+	case LINEAR_MIPMAP_LINEAR: return GL_LINEAR_MIPMAP_LINEAR;
+	default: throw invalid_argument("get_gl_filter");
+	}
+}
+
+GLenum get_gl_wrap(TextureWrap wrap)
+{
+	switch(wrap)
+	{
+	case REPEAT: return GL_REPEAT;
+	case CLAMP_TO_EDGE: return GL_CLAMP_TO_EDGE;
+	case CLAMP_TO_BORDER: return GL_CLAMP_TO_BORDER;
+	case MIRRORED_REPEAT: return GL_MIRRORED_REPEAT;
+	default: throw invalid_argument("get_gl_wrap");
+	}
+}
+
 void operator>>(const LexicalConverter &c, TextureFilter &tf)
 {
 	if(c.get()=="NEAREST")
diff --git a/source/core/sampler.h b/source/core/sampler.h
index 43d1e541..524a8fc5 100644
--- a/source/core/sampler.h
+++ b/source/core/sampler.h
@@ -12,38 +12,38 @@ namespace GL {
 enum TextureFilter
 {
 	/// No filtering
-	NEAREST = GL_NEAREST,
+	NEAREST,
 
 	/// Bilinear filtering
-	LINEAR = GL_LINEAR,
+	LINEAR,
 
 	/// Mipmapping without filtering
-	NEAREST_MIPMAP_NEAREST = GL_NEAREST_MIPMAP_NEAREST,
+	NEAREST_MIPMAP_NEAREST,
 
 	/// Linear filtering between two mipmap levels
-	NEAREST_MIPMAP_LINEAR = GL_NEAREST_MIPMAP_LINEAR,
+	NEAREST_MIPMAP_LINEAR,
 
 	/// Bilinear filtering on the closest mipmap level
-	LINEAR_MIPMAP_NEAREST = GL_LINEAR_MIPMAP_NEAREST,
+	LINEAR_MIPMAP_NEAREST,
 
 	/// Trilinear filtering between two mipmap levels
-	LINEAR_MIPMAP_LINEAR = GL_LINEAR_MIPMAP_LINEAR
+	LINEAR_MIPMAP_LINEAR
 };
 
 
 enum TextureWrap
 {
 	/// Tile the texture infinitely
-	REPEAT = GL_REPEAT,
+	REPEAT,
 
 	/// Extend the texels at the edge of the texture to infinity
-	CLAMP_TO_EDGE = GL_CLAMP_TO_EDGE,
+	CLAMP_TO_EDGE,
 
 	/// Sampling outside the texture will return border color
-	CLAMP_TO_BORDER = GL_CLAMP_TO_BORDER,
+	CLAMP_TO_BORDER,
 
 	/// Tile the texture, with every other repetition mirrored
-	MIRRORED_REPEAT = GL_MIRRORED_REPEAT
+	MIRRORED_REPEAT
 };
 
 
@@ -159,6 +159,8 @@ public:
 
 
 bool is_mipmapped(TextureFilter);
+GLenum get_gl_filter(TextureFilter);
+GLenum get_gl_wrap(TextureWrap);
 
 void operator>>(const LexicalConverter &, TextureFilter &);
 void operator>>(const LexicalConverter &, TextureWrap &);
-- 
2.43.0