OpenSubdiv: Re-work C-API integration

Main goal is to make API simpler to follow (at least ion terms what
is defined/declared where, as opposite of handful big headers which
includes all the declarations), and also avoid a big set of long and
obscure functions.

Now C-API files are split into smaller ones, following OpenSubdiv
behavior more closely, and also function pointers in structures
used a lot more, which shortens functions names,

UV integration part in GL Mesh is mainly stripped away, it needs
to be done differently. On a related topic, UV coordinates API in
converter needs to be removed as well, we do not need coordinates,
only island connectivity information there.

Additional changes:

- Varying interpolation in evaluator API are temporarily disabled,
  need to extend API somewhere (probably, evaluator's API) to inform
  layout information of vertex data (whether it contains varying
  data, width, stride and such).

- Evaluator now can interpolate face-varying data.
  Only works for adaptive refiner, since some issues in OpenSubdiv
  itself.

Planned changes:

- Remove uv coordinates from TopologyConverter.
- Support evaluation of patches (as opposite to individual coordinates
  as it happens currently).
- Support more flexible layout of varying and face-varying data.
  It is stupid to assume varying is 3 floats and face-varying 2 floats.
- Support of second order derivatives.
- Everything else what i'm missing in this list.

1 files changed, 65 insertions, 74 deletions

diff --git a/source/blender/blenkernel/intern/CCGSubSurf_opensubdiv.c b/source/blender/blenkernel/intern/CCGSubSurf_opensubdiv.c
index 46204898709..98a17ad8009 100644
--- a/source/blender/blenkernel/intern/CCGSubSurf_opensubdiv.c
+++ b/source/blender/blenkernel/intern/CCGSubSurf_opensubdiv.c
@@ -42,6 +42,9 @@
 
 #include "opensubdiv_capi.h"
 #include "opensubdiv_converter_capi.h"
+#include "opensubdiv_evaluator_capi.h"
+#include "opensubdiv_gl_mesh_capi.h"
+#include "opensubdiv_topology_refiner_capi.h"
 
 #include "GPU_glew.h"
 #include "GPU_extensions.h"
@@ -131,7 +134,6 @@ static bool compare_ccg_derivedmesh_topology(CCGSubSurf *ss, DerivedMesh *dm)
 
 static bool compare_osd_derivedmesh_topology(CCGSubSurf *ss, DerivedMesh *dm)
 {
-	const OpenSubdiv_TopologyRefinerDescr *topology_refiner;
 	OpenSubdiv_Converter converter;
 	bool result;
 	if (ss->osd_mesh == NULL && ss->osd_topology_refiner == NULL) {
@@ -140,15 +142,10 @@ static bool compare_osd_derivedmesh_topology(CCGSubSurf *ss, DerivedMesh *dm)
 	/* TODO(sergey): De-duplicate with topology counter at the bottom of
 	 * the file.
 	 */
-	if (ss->osd_topology_refiner != NULL) {
-		topology_refiner = ss->osd_topology_refiner;
-	}
-	else {
-		topology_refiner = openSubdiv_getGLMeshTopologyRefiner(ss->osd_mesh);
-	}
 	ccgSubSurf_converter_setup_from_derivedmesh(ss, dm, &converter);
-	result = openSubdiv_topologyRefnerCompareConverter(topology_refiner,
-	                                                   &converter);
+	result = openSubdiv_topologyRefinerCompareWithConverter(
+	        ss->osd_topology_refiner,
+	        &converter);
 	ccgSubSurf_converter_free(&converter);
 	return result;
 }
@@ -159,22 +156,13 @@ static bool opensubdiv_is_topology_changed(CCGSubSurf *ss, DerivedMesh *dm)
 		return true;
 	}
 	if (ss->osd_topology_refiner != NULL) {
-		int levels = openSubdiv_topologyRefinerGetSubdivLevel(
+		const int levels = ss->osd_topology_refiner->getSubdivisionLevel(
 		        ss->osd_topology_refiner);
 		BLI_assert(ss->osd_mesh_invalid == true);
 		if (levels != ss->subdivLevels) {
 			return true;
 		}
 	}
-	if (ss->osd_mesh != NULL && ss->osd_mesh_invalid == false) {
-		const OpenSubdiv_TopologyRefinerDescr *topology_refiner =
-		        openSubdiv_getGLMeshTopologyRefiner(ss->osd_mesh);
-		int levels = openSubdiv_topologyRefinerGetSubdivLevel(topology_refiner);
-		BLI_assert(ss->osd_topology_refiner == NULL);
-		if (levels != ss->subdivLevels) {
-			return true;
-		}
-	}
 	if (ss->skip_grids == false) {
 		return compare_ccg_derivedmesh_topology(ss, dm) == false;
 	}
@@ -194,13 +182,13 @@ void ccgSubSurf_checkTopologyChanged(CCGSubSurf *ss, DerivedMesh *dm)
 		/* Reset GPU part. */
 		ss->osd_mesh_invalid = true;
 		if (ss->osd_topology_refiner != NULL) {
-			openSubdiv_deleteTopologyRefinerDescr(ss->osd_topology_refiner);
+			openSubdiv_deleteTopologyRefiner(ss->osd_topology_refiner);
 			ss->osd_topology_refiner = NULL;
 		}
 
 		/* Reset CPU side. */
 		if (ss->osd_evaluator != NULL) {
-			openSubdiv_deleteEvaluatorDescr(ss->osd_evaluator);
+			openSubdiv_deleteEvaluator(ss->osd_evaluator);
 			ss->osd_evaluator = NULL;
 		}
 	}
@@ -209,10 +197,10 @@ void ccgSubSurf_checkTopologyChanged(CCGSubSurf *ss, DerivedMesh *dm)
 static void ccgSubSurf__updateGLMeshCoords(CCGSubSurf *ss)
 {
 	BLI_assert(ss->meshIFC.numLayers == 3);
-	openSubdiv_osdGLMeshUpdateVertexBuffer(ss->osd_mesh,
-	                                       (float *) ss->osd_coarse_coords,
-	                                       0,
-	                                       ss->osd_num_coarse_coords);
+	ss->osd_mesh->setCoarsePositions(ss->osd_mesh,
+	                                 (float *) ss->osd_coarse_coords,
+	                                 0,
+	                                 ss->osd_num_coarse_coords);
 }
 
 bool ccgSubSurf_prepareGLMesh(CCGSubSurf *ss,
@@ -259,9 +247,7 @@ bool ccgSubSurf_prepareGLMesh(CCGSubSurf *ss,
 
 		ss->osd_mesh = openSubdiv_createOsdGLMeshFromTopologyRefiner(
 		        ss->osd_topology_refiner,
-		        compute_type,
-		        ss->subdivLevels);
-		ss->osd_topology_refiner = NULL;
+		        compute_type);
 
 		if (UNLIKELY(ss->osd_mesh == NULL)) {
 			/* Most likely compute device is not available. */
@@ -269,13 +255,12 @@ bool ccgSubSurf_prepareGLMesh(CCGSubSurf *ss,
 		}
 
 		ccgSubSurf__updateGLMeshCoords(ss);
-		openSubdiv_osdGLMeshRefine(ss->osd_mesh);
-		openSubdiv_osdGLMeshSynchronize(ss->osd_mesh);
+		ss->osd_mesh->refine(ss->osd_mesh);
+		ss->osd_mesh->synchronize(ss->osd_mesh);
 		ss->osd_coarse_coords_invalid = false;
 
 		glBindVertexArray(ss->osd_vao);
-		glBindBuffer(GL_ARRAY_BUFFER,
-		             openSubdiv_getOsdGLMeshVertexBuffer(ss->osd_mesh));
+		ss->osd_mesh->bindVertexBuffer(ss->osd_mesh);
 
 		glEnableVertexAttribArray(0);
 		glEnableVertexAttribArray(1);
@@ -289,12 +274,12 @@ bool ccgSubSurf_prepareGLMesh(CCGSubSurf *ss,
 	}
 	else if (ss->osd_coarse_coords_invalid) {
 		ccgSubSurf__updateGLMeshCoords(ss);
-		openSubdiv_osdGLMeshRefine(ss->osd_mesh);
-		openSubdiv_osdGLMeshSynchronize(ss->osd_mesh);
+		ss->osd_mesh->refine(ss->osd_mesh);
+		ss->osd_mesh->synchronize(ss->osd_mesh);
 		ss->osd_coarse_coords_invalid = false;
 	}
 
-	openSubdiv_osdGLMeshDisplayPrepare(use_osd_glsl, active_uv_index);
+	ss->osd_mesh->prepareDraw(ss->osd_mesh, use_osd_glsl, active_uv_index);
 
 	return true;
 }
@@ -305,12 +290,12 @@ void ccgSubSurf_drawGLMesh(CCGSubSurf *ss, bool fill_quads,
 	if (LIKELY(ss->osd_mesh != NULL)) {
 		glBindVertexArray(ss->osd_vao);
 		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,
-		             openSubdiv_getOsdGLMeshPatchIndexBuffer(ss->osd_mesh));
+		             ss->osd_mesh->getPatchIndexBuffer(ss->osd_mesh));
 
-		openSubdiv_osdGLMeshBindVertexBuffer(ss->osd_mesh);
+		ss->osd_mesh->bindVertexBuffer(ss->osd_mesh);
 		glBindVertexArray(ss->osd_vao);
-		openSubdiv_osdGLMeshDisplay(ss->osd_mesh, fill_quads,
-		                            start_partition, num_partitions);
+		ss->osd_mesh->drawPatches(ss->osd_mesh, fill_quads,
+		                          start_partition, num_partitions);
 		glBindVertexArray(0);
 		glBindBuffer(GL_ARRAY_BUFFER, 0);
 		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
@@ -319,33 +304,21 @@ void ccgSubSurf_drawGLMesh(CCGSubSurf *ss, bool fill_quads,
 
 int ccgSubSurf_getNumGLMeshBaseFaces(CCGSubSurf *ss)
 {
-	const OpenSubdiv_TopologyRefinerDescr *topology_refiner;
 	if (ss->osd_topology_refiner != NULL) {
-		topology_refiner = ss->osd_topology_refiner;
-	}
-	else if (ss->osd_mesh != NULL) {
-		topology_refiner = openSubdiv_getGLMeshTopologyRefiner(ss->osd_mesh);
-	}
-	else {
-		return 0;
+		return ss->osd_topology_refiner->getNumFaces(
+		        ss->osd_topology_refiner);
 	}
-	return openSubdiv_topologyRefinerGetNumFaces(topology_refiner);
+	return 0;
 }
 
 /* Get number of vertices in base faces in a particular GL mesh. */
 int ccgSubSurf_getNumGLMeshBaseFaceVerts(CCGSubSurf *ss, int face)
 {
-	const OpenSubdiv_TopologyRefinerDescr *topology_refiner;
 	if (ss->osd_topology_refiner != NULL) {
-		topology_refiner = ss->osd_topology_refiner;
-	}
-	else if (ss->osd_mesh != NULL) {
-		topology_refiner = openSubdiv_getGLMeshTopologyRefiner(ss->osd_mesh);
-	}
-	else {
-		return 0;
+		return ss->osd_topology_refiner->getNumFaceVertices(
+		        ss->osd_topology_refiner, face);
 	}
-	return openSubdiv_topologyRefinerGetNumFaceVerts(topology_refiner, face);
+	return 0;
 }
 
 void ccgSubSurf_setSkipGrids(CCGSubSurf *ss, bool skip_grids)
@@ -453,17 +426,21 @@ void ccgSubSurf_evaluatorFVarUV(CCGSubSurf *ss,
 static bool opensubdiv_createEvaluator(CCGSubSurf *ss)
 {
 	OpenSubdiv_Converter converter;
-	OpenSubdiv_TopologyRefinerDescr *topology_refiner;
+	OpenSubdiv_TopologyRefiner *topology_refiner;
 	if (ss->fMap->numEntries == 0) {
 		/* OpenSubdiv doesn't support meshes without faces. */
 		return false;
 	}
 	ccgSubSurf_converter_setup_from_ccg(ss, &converter);
-	topology_refiner = openSubdiv_createTopologyRefinerDescr(&converter);
+	OpenSubdiv_TopologyRefinerSettings settings;
+	settings.level = ss->subdivLevels;
+	settings.is_adaptive = false;
+	topology_refiner =
+	        openSubdiv_createTopologyRefinerFromConverter(
+	                &converter, &settings);
 	ccgSubSurf_converter_free(&converter);
 	ss->osd_evaluator =
-	        openSubdiv_createEvaluatorDescr(topology_refiner,
-	                                        ss->subdivLevels);
+	        openSubdiv_createEvaluatorFromTopologyRefiner(topology_refiner);
 	if (ss->osd_evaluator == NULL) {
 		BLI_assert(!"OpenSubdiv initialization failed, should not happen.");
 		return false;
@@ -519,11 +496,11 @@ static void opensubdiv_updateEvaluatorCoarsePositions(CCGSubSurf *ss)
 		}
 	}
 
-	openSubdiv_setEvaluatorCoarsePositions(ss->osd_evaluator,
-	                                       (float *)positions,
-	                                       0,
-	                                       num_basis_verts);
-	openSubdiv_refineEvaluator(ss->osd_evaluator);
+	ss->osd_evaluator->setCoarsePositions(ss->osd_evaluator,
+	                                      (float *)positions,
+	                                      0,
+	                                      num_basis_verts);
+	ss->osd_evaluator->refine(ss->osd_evaluator);
 
 	MEM_freeN(positions);
 }
@@ -558,11 +535,12 @@ static void opensubdiv_evaluateQuadFaceGrids(CCGSubSurf *ss,
 				ccgSubSurf__mapGridToFace(S, grid_u, grid_v, &face_u, &face_v);
 
 				/* TODO(sergey): Need proper port. */
-				openSubdiv_evaluateLimit(ss->osd_evaluator, osd_face_index,
-				                         face_u, face_v,
-				                         P,
-				                         do_normals ? dPdu : NULL,
-				                         do_normals ? dPdv : NULL);
+				ss->osd_evaluator->evaluateLimit(
+				        ss->osd_evaluator, osd_face_index,
+				        face_u, face_v,
+				        P,
+				        do_normals ? dPdu : NULL,
+				        do_normals ? dPdv : NULL);
 
 				OSD_LOG("face=%d, corner=%d, grid_u=%f, grid_v=%f, face_u=%f, face_v=%f, P=(%f, %f, %f)\n",
 				        osd_face_index, S, grid_u, grid_v, face_u, face_v, P[0], P[1], P[2]);
@@ -636,7 +614,11 @@ static void opensubdiv_evaluateQuadFaceGrids(CCGSubSurf *ss,
 			 * let's just re-evaluate for simplicity.
 			 */
 			/* TODO(sergey): Need proper port. */
-			openSubdiv_evaluateLimit(ss->osd_evaluator, osd_face_index, u, v, P, dPdu, dPdv);
+			ss->osd_evaluator->evaluateLimit(
+			        ss->osd_evaluator,
+			        osd_face_index,
+			        u, v,
+			        P, dPdu, dPdv);
 			VertDataCopy(co, P, ss);
 			if (do_normals) {
 				cross_v3_v3v3(no, dPdu, dPdv);
@@ -700,7 +682,11 @@ static void opensubdiv_evaluateNGonFaceGrids(CCGSubSurf *ss,
 				float P[3], dPdu[3], dPdv[3];
 
 				/* TODO(sergey): Need proper port. */
-				openSubdiv_evaluateLimit(ss->osd_evaluator, osd_face_index + S, u, v, P, dPdu, dPdv);
+				ss->osd_evaluator->evaluateLimit(
+				        ss->osd_evaluator,
+				        osd_face_index + S,
+				        u, v,
+				        P, dPdu, dPdv);
 
 				OSD_LOG("face=%d, corner=%d, u=%f, v=%f, P=(%f, %f, %f)\n",
 				        osd_face_index + S, S, u, v, P[0], P[1], P[2]);
@@ -838,7 +824,12 @@ void ccgSubSurf_prepareTopologyRefiner(CCGSubSurf *ss, DerivedMesh *dm)
 			OpenSubdiv_Converter converter;
 			ccgSubSurf_converter_setup_from_derivedmesh(ss, dm, &converter);
 			/* TODO(sergey): Remove possibly previously allocated refiner. */
-			ss->osd_topology_refiner = openSubdiv_createTopologyRefinerDescr(&converter);
+			OpenSubdiv_TopologyRefinerSettings settings;
+			settings.level = ss->subdivLevels;
+			settings.is_adaptive = false;
+			ss->osd_topology_refiner =
+			        openSubdiv_createTopologyRefinerFromConverter(
+			                &converter, &settings);
 			ccgSubSurf_converter_free(&converter);
 		}
 	}