Mesh Batch Cache: Define Compressed format for shading data.

Deactivated by default.
All shading attribs can be packed to take less VRAM at the cost of precision (not noticable in this case).
UVs can be packed into I16 but that limits their positions into the [-1, +1] range.

This could be a setting option in the future.

3 files changed, 91 insertions, 15 deletions

diff --git a/source/blender/blenlib/BLI_math_vector.h b/source/blender/blenlib/BLI_math_vector.h
index dc9432fef64..3a34a199ba8 100644
--- a/source/blender/blenlib/BLI_math_vector.h
+++ b/source/blender/blenlib/BLI_math_vector.h
@@ -321,6 +321,7 @@ void print_vn(const char *str, const float v[], const int n);
 #define print_v4_id(v) print_v4(STRINGIFY(v), v)
 #define print_vn_id(v, n) print_vn(STRINGIFY(v), v, n)
 
+MINLINE void normal_float_to_short_v2(short r[2], const float n[2]);
 MINLINE void normal_short_to_float_v3(float r[3], const short n[3]);
 MINLINE void normal_float_to_short_v3(short r[3], const float n[3]);
 
diff --git a/source/blender/blenlib/intern/math_vector_inline.c b/source/blender/blenlib/intern/math_vector_inline.c
index 4389cd29034..75bbfda3f5b 100644
--- a/source/blender/blenlib/intern/math_vector_inline.c
+++ b/source/blender/blenlib/intern/math_vector_inline.c
@@ -960,6 +960,12 @@ MINLINE float normalize_v3(float n[3])
 	return normalize_v3_v3(n, n);
 }
 
+MINLINE void normal_float_to_short_v2(short out[2], const float in[2])
+{
+	out[0] = (short) (in[0] * 32767.0f);
+	out[1] = (short) (in[1] * 32767.0f);
+}
+
 MINLINE void normal_short_to_float_v3(float out[3], const short in[3])
 {
 	out[0] = in[0] * (1.0f / 32767.0f);
diff --git a/source/blender/draw/intern/draw_cache_impl_mesh.c b/source/blender/draw/intern/draw_cache_impl_mesh.c
index 264875ef131..37ecf89bf26 100644
--- a/source/blender/draw/intern/draw_cache_impl_mesh.c
+++ b/source/blender/draw/intern/draw_cache_impl_mesh.c
@@ -1917,6 +1917,7 @@ void DRW_mesh_batch_cache_free(Mesh *me)
 
 /* Batch cache usage. */
 
+//#define USE_COMP_MESH_DATA
 static VertexBuffer *mesh_batch_cache_get_tri_shading_data(MeshRenderData *rdata, MeshBatchCache *cache)
 {
 	BLI_assert(rdata->types & (MR_DATATYPE_VERT | MR_DATATYPE_LOOPTRI | MR_DATATYPE_LOOP | MR_DATATYPE_POLY));
@@ -1930,7 +1931,11 @@ static VertexBuffer *mesh_batch_cache_get_tri_shading_data(MeshRenderData *rdata
 		VertexFormat_clear(format);
 
 		/* initialize vertex format */
+#ifdef USE_COMP_MESH_DATA
+		unsigned int orco_id = VertexFormat_add_attrib(format, "orco", COMP_I16, 3, NORMALIZE_INT_TO_FLOAT);
+#else
 		unsigned int orco_id = VertexFormat_add_attrib(format, "orco", COMP_F32, 3, KEEP_FLOAT);
+#endif
 		unsigned int *uv_id = MEM_mallocN(sizeof(*uv_id) * rdata->uv_len, "UV attrib format");
 		unsigned int *vcol_id = MEM_mallocN(sizeof(*vcol_id) * rdata->vcol_len, "Vcol attrib format");
 		unsigned int *tangent_id = MEM_mallocN(sizeof(*tangent_id) * rdata->uv_len, "Tangent attrib format");
@@ -1938,7 +1943,11 @@ static VertexBuffer *mesh_batch_cache_get_tri_shading_data(MeshRenderData *rdata
 		for (int i = 0; i < rdata->uv_len; i++) {
 			/* UV */
 			attrib_name = mesh_render_data_uv_layer_uuid_get(rdata, i);
+#ifdef USE_COMP_MESH_DATA
+			uv_id[i] = VertexFormat_add_attrib(format, attrib_name, COMP_I16, 2, NORMALIZE_INT_TO_FLOAT);
+#else
 			uv_id[i] = VertexFormat_add_attrib(format, attrib_name, COMP_F32, 2, KEEP_FLOAT);
+#endif
 
 			/* Auto Name */
 			attrib_name = mesh_render_data_uv_auto_layer_uuid_get(rdata, i);
@@ -1950,7 +1959,15 @@ static VertexBuffer *mesh_batch_cache_get_tri_shading_data(MeshRenderData *rdata
 
 			/* Tangent */
 			attrib_name = mesh_render_data_tangent_layer_uuid_get(rdata, i);
+#ifdef USE_COMP_MESH_DATA
+#  if USE_10_10_10
+			tangent_id[i] = VertexFormat_add_attrib(format, attrib_name, COMP_I10, 3, NORMALIZE_INT_TO_FLOAT);
+#  else
+			tangent_id[i] = VertexFormat_add_attrib(format, attrib_name, COMP_I16, 3, NORMALIZE_INT_TO_FLOAT);
+#  endif
+#else
 			tangent_id[i] = VertexFormat_add_attrib(format, attrib_name, COMP_F32, 3, KEEP_FLOAT);
+#endif
 
 			if (i == rdata->uv_active) {
 				VertexFormat_add_alias(format, "t");
@@ -1990,15 +2007,41 @@ static VertexBuffer *mesh_batch_cache_get_tri_shading_data(MeshRenderData *rdata
 			{
 				/* UVs & TANGENTs */
 				for (int j = 0; j < rdata->uv_len; j++) {
+					/* UVs */
 					mesh_render_data_looptri_uvs_get(rdata, i, j, &tri_uvs);
-					VertexBuffer_set_attrib(vbo, uv_id[j], vidx + 0, tri_uvs[0]);
-					VertexBuffer_set_attrib(vbo, uv_id[j], vidx + 1, tri_uvs[1]);
-					VertexBuffer_set_attrib(vbo, uv_id[j], vidx + 2, tri_uvs[2]);
+#ifdef USE_COMP_MESH_DATA
+					short s_uvs[3][2];
+					normal_float_to_short_v2(s_uvs[0], tri_uvs[0]);
+					normal_float_to_short_v2(s_uvs[1], tri_uvs[1]);
+					normal_float_to_short_v2(s_uvs[2], tri_uvs[2]);
+#else
+					float **s_uvs = tri_uvs;
+#endif
+					VertexBuffer_set_attrib(vbo, uv_id[j], vidx + 0, s_uvs[0]);
+					VertexBuffer_set_attrib(vbo, uv_id[j], vidx + 1, s_uvs[1]);
+					VertexBuffer_set_attrib(vbo, uv_id[j], vidx + 2, s_uvs[2]);
 
+					/* Tangent */
 					mesh_render_data_looptri_tans_get(rdata, i, j, &tri_tans);
-					VertexBuffer_set_attrib(vbo, tangent_id[j], vidx + 0, tri_tans[0]);
-					VertexBuffer_set_attrib(vbo, tangent_id[j], vidx + 1, tri_tans[1]);
-					VertexBuffer_set_attrib(vbo, tangent_id[j], vidx + 2, tri_tans[2]);
+#ifdef USE_COMP_MESH_DATA
+#  if USE_10_10_10
+					PackedNormal s_tan[3] = {
+					    convert_i10_v3(tri_tans[0]),
+					    convert_i10_v3(tri_tans[1]),
+					    convert_i10_v3(tri_tans[2])
+					};
+#  else
+					short s_tan[3][3];
+					normal_float_to_short_v3(s_tan[0], tri_tans[0]);
+					normal_float_to_short_v3(s_tan[1], tri_tans[1]);
+					normal_float_to_short_v3(s_tan[2], tri_tans[2]);
+#  endif
+#else
+					float **s_tan = tri_tans;
+#endif
+					VertexBuffer_set_attrib(vbo, tangent_id[j], vidx + 0, s_tan[0]);
+					VertexBuffer_set_attrib(vbo, tangent_id[j], vidx + 1, s_tan[1]);
+					VertexBuffer_set_attrib(vbo, tangent_id[j], vidx + 2, s_tan[2]);
 				}
 
 				/* VCOLs */
@@ -2011,9 +2054,17 @@ static VertexBuffer *mesh_batch_cache_get_tri_shading_data(MeshRenderData *rdata
 
 				/* ORCO */
 				mesh_render_data_looptri_orcos_get(rdata, i, &tri_orcos);
-				VertexBuffer_set_attrib(vbo, orco_id, vidx++, tri_orcos[0]);
-				VertexBuffer_set_attrib(vbo, orco_id, vidx++, tri_orcos[1]);
-				VertexBuffer_set_attrib(vbo, orco_id, vidx++, tri_orcos[2]);
+#ifdef USE_COMP_MESH_DATA
+				short s_orco[3][3];
+				normal_float_to_short_v3(s_orco[0], tri_orcos[0]);
+				normal_float_to_short_v3(s_orco[1], tri_orcos[1]);
+				normal_float_to_short_v3(s_orco[2], tri_orcos[2]);
+#else
+				float **s_orco = tri_orcos;
+#endif
+				VertexBuffer_set_attrib(vbo, orco_id, vidx++, s_orco[0]);
+				VertexBuffer_set_attrib(vbo, orco_id, vidx++, s_orco[1]);
+				VertexBuffer_set_attrib(vbo, orco_id, vidx++, s_orco[2]);
 			}
 		}
 		vbo_len_used = vidx;
@@ -2042,7 +2093,11 @@ static VertexBuffer *mesh_batch_cache_get_tri_pos_and_normals(
 		if (format.attrib_ct == 0) {
 			/* initialize vertex format */
 			pos_id = VertexFormat_add_attrib(&format, "pos", COMP_F32, 3, KEEP_FLOAT);
+#if USE_10_10_10
+			nor_id = VertexFormat_add_attrib(&format, "nor", COMP_I10, 3, NORMALIZE_INT_TO_FLOAT);
+#else
 			nor_id = VertexFormat_add_attrib(&format, "nor", COMP_I16, 3, NORMALIZE_INT_TO_FLOAT);
+#endif
 		}
 
 		const int tri_len = mesh_render_data_looptri_len_get(rdata);
@@ -2062,14 +2117,28 @@ static VertexBuffer *mesh_batch_cache_get_tri_pos_and_normals(
 			        rdata, i, &tri_vert_cos, &tri_nor, &tri_vert_nors, &is_smooth))
 			{
 				if (is_smooth) {
-					VertexBuffer_set_attrib(vbo, nor_id, nidx++, tri_vert_nors[0]);
-					VertexBuffer_set_attrib(vbo, nor_id, nidx++, tri_vert_nors[1]);
-					VertexBuffer_set_attrib(vbo, nor_id, nidx++, tri_vert_nors[2]);
+#if USE_10_10_10
+					PackedNormal snor[3] = {
+						convert_i10_s3(tri_vert_nors[0]),
+						convert_i10_s3(tri_vert_nors[1]),
+						convert_i10_s3(tri_vert_nors[2])
+					}
+#else
+					short **snor = tri_vert_nors;
+#endif
+					VertexBuffer_set_attrib(vbo, nor_id, nidx++, snor[0]);
+					VertexBuffer_set_attrib(vbo, nor_id, nidx++, snor[1]);
+					VertexBuffer_set_attrib(vbo, nor_id, nidx++, snor[2]);
 				}
 				else {
-					VertexBuffer_set_attrib(vbo, nor_id, nidx++, tri_nor);
-					VertexBuffer_set_attrib(vbo, nor_id, nidx++, tri_nor);
-					VertexBuffer_set_attrib(vbo, nor_id, nidx++, tri_nor);
+#if USE_10_10_10
+					PackedNormal snor = convert_i10_s3(tri_nor);
+#else
+					short *snor = tri_nor;
+#endif
+					VertexBuffer_set_attrib(vbo, nor_id, nidx++, snor);
+					VertexBuffer_set_attrib(vbo, nor_id, nidx++, snor);
+					VertexBuffer_set_attrib(vbo, nor_id, nidx++, snor);
 				}
 
 				VertexBuffer_set_attrib(vbo, pos_id, vidx++, tri_vert_cos[0]);