[Bf-blender-cvs] [8fd510f] blender2.8: Gawain: new enum type for vertex attrib components

[Mike Erwin]

Commit: 8fd510f4b84a1cdcdd484948afc2087cf28cb1c5
Author: Mike Erwin
Date:   Fri Nov 11 19:39:56 2016 -0600
Branches: blender2.8
https://developer.blender.org/rB8fd510f4b84a1cdcdd484948afc2087cf28cb1c5

Gawain: new enum type for vertex attrib components

Motivations:
1) GLenum is too broad; tightly-defined enum just for this is safer.
2) enable a Vulkan future

New code should use these instead of GL_FLOAT etc. When all existing code has been updated to use new enum, we can drop compatibility with GLenum values.

Early work towards 10_10_10 format, more to come soon.

===================================================================

M	source/blender/gpu/gawain/vertex_format.c
M	source/blender/gpu/gawain/vertex_format.h

===================================================================

diff --git a/source/blender/gpu/gawain/vertex_format.c b/source/blender/gpu/gawain/vertex_format.c
index 20a4d7d..8947855 100644
--- a/source/blender/gpu/gawain/vertex_format.c
+++ b/source/blender/gpu/gawain/vertex_format.c
@@ -36,7 +36,7 @@ void VertexFormat_copy(VertexFormat* dest, const VertexFormat* src)
 	memcpy(dest, src, sizeof(VertexFormat));
 	}
 
-static unsigned comp_sz(GLenum type)
+static unsigned comp_sz(VertexCompType type)
 	{
 #if TRUST_NO_ONE
 	assert(type >= GL_BYTE && type <= GL_FLOAT);
@@ -48,11 +48,21 @@ static unsigned comp_sz(GLenum type)
 
 static unsigned attrib_sz(const Attrib *a)
 	{
+#if USE_10_10_10
+	if (a->comp_type == COMP_I10)
+		return 4; // always packed as 10_10_10_2
+#endif
+
 	return a->comp_ct * comp_sz(a->comp_type);
 	}
 
 static unsigned attrib_align(const Attrib *a)
 	{
+#if USE_10_10_10
+	if (a->comp_type == COMP_I10)
+		return 4; // always packed as 10_10_10_2
+#endif
+
 	unsigned c = comp_sz(a->comp_type);
 	if (a->comp_ct == 3 && c <= 2)
 		return 4 * c; // AMD HW can't fetch these well, so pad it out (other vendors too?)
@@ -96,7 +106,7 @@ static const char* copy_attrib_name(VertexFormat* format, const char* name)
 	return name_copy;
 	}
 
-unsigned add_attrib(VertexFormat* format, const char* name, GLenum comp_type, unsigned comp_ct, VertexFetchMode fetch_mode)
+unsigned add_attrib(VertexFormat* format, const char* name, VertexCompType comp_type, unsigned comp_ct, VertexFetchMode fetch_mode)
 	{
 #if TRUST_NO_ONE
 	assert(format->attrib_ct < MAX_VERTEX_ATTRIBS); // there's room for more
@@ -104,27 +114,19 @@ unsigned add_attrib(VertexFormat* format, const char* name, GLenum comp_type, un
 	assert(comp_ct >= 1 && comp_ct <= 4);
 	switch (comp_type)
 		{
-		case GL_FLOAT:
+		case COMP_F32:
 			// float type can only kept as float
 			assert(fetch_mode == KEEP_FLOAT);
 			break;
-	#if 0 // enable this after switching to our own enum for comp_type
+ #if USE_10_10_10
+		case COMP_I10:
+			assert(comp_ct == 3); // 10_10_10 format intended for normals (xyz) or colors (rgb)
+			assert(fetch_mode == NORMALIZE_INT_TO_FLOAT);
+			break;
+ #endif
 		default:
 			// integer types can be kept as int or converted/normalized to float
 			assert(fetch_mode != KEEP_FLOAT);
-	#else
-		case GL_BYTE:
-		case GL_UNSIGNED_BYTE:
-		case GL_SHORT:
-		case GL_UNSIGNED_SHORT:
-		case GL_INT:
-		case GL_UNSIGNED_INT:
-			// integer types can be converted, normalized, or kept as int
-			assert(fetch_mode != KEEP_FLOAT);
-			break;
-		default:
-			assert(false); // invalid comp_type
-	#endif
 		}
 #endif
 
diff --git a/source/blender/gpu/gawain/vertex_format.h b/source/blender/gpu/gawain/vertex_format.h
index 09c7960..8bf20d5 100644
--- a/source/blender/gpu/gawain/vertex_format.h
+++ b/source/blender/gpu/gawain/vertex_format.h
@@ -17,6 +17,25 @@
 #define AVG_VERTEX_ATTRIB_NAME_LEN 5
 #define VERTEX_ATTRIB_NAMES_BUFFER_LEN ((AVG_VERTEX_ATTRIB_NAME_LEN + 1) * MAX_VERTEX_ATTRIBS)
 
+#define USE_10_10_10 0
+// (GLEW_VERSION_3_3 || GLEW_ARB_vertex_type_2_10_10_10_rev)
+//   ^-- this is only guaranteed on Windows right now, will be true on all platforms soon
+
+typedef enum {
+	COMP_I8 = GL_BYTE,
+	COMP_U8 = GL_UNSIGNED_BYTE,
+	COMP_I16 = GL_SHORT,
+	COMP_U16 = GL_UNSIGNED_SHORT,
+	COMP_I32 = GL_INT,
+	COMP_U32 = GL_UNSIGNED_INT,
+
+	COMP_F32 = GL_FLOAT, // TODO: drop the GL_ equivalence here, use a private lookup table
+
+#if USE_10_10_10
+	COMP_I10 = GL_INT_2_10_10_10_REV
+#endif
+} VertexCompType;
+
 typedef enum {
 	KEEP_FLOAT,
 	KEEP_INT,
@@ -25,7 +44,7 @@ typedef enum {
 } VertexFetchMode;
 
 typedef struct {
-	GLenum comp_type;
+	VertexCompType comp_type;
 	unsigned comp_ct; // 1 to 4
 	unsigned sz; // size in bytes, 1 to 16
 	unsigned offset; // from beginning of vertex, in bytes
@@ -45,7 +64,7 @@ typedef struct {
 void VertexFormat_clear(VertexFormat*);
 void VertexFormat_copy(VertexFormat* dest, const VertexFormat* src);
 
-unsigned add_attrib(VertexFormat*, const char* name, GLenum comp_type, unsigned comp_ct, VertexFetchMode);
+unsigned add_attrib(VertexFormat*, const char* name, VertexCompType, unsigned comp_ct, VertexFetchMode);
 
 // for internal use
 void VertexFormat_pack(VertexFormat*);