Curve Edit: Cleanup/Improve/Fix handles drawing

Now handles are drawn using index buffer instead of duplicating memory
requirement.

Also make use of shader tricks to draw handles antialiased, and respond to
UI scalling.

Make vertex point match edit mesh vertex size.

1 files changed, 27 insertions, 62 deletions

diff --git a/source/blender/draw/intern/draw_cache_impl_curve.c b/source/blender/draw/intern/draw_cache_impl_curve.c
index f2b303207fd..0f06f360b4a 100644
--- a/source/blender/draw/intern/draw_cache_impl_curve.c
+++ b/source/blender/draw/intern/draw_cache_impl_curve.c
@@ -45,14 +45,11 @@
 #include "draw_cache_impl.h"  /* own include */
 
 #define SELECT            1
-#define ACTIVE_NURB       1 << 7 /* last char bite */
-#define HANDLE_SEL_OFFSET (TH_HANDLE_SEL_FREE - TH_HANDLE_FREE)
+#define ACTIVE_NURB       1 << 2
 
 /* Used as values of `color_id` in `edit_curve_overlay_handle_geom.glsl` */
 enum {
-	COLOR_NURB_ULINE_ID = TH_HANDLE_SEL_AUTOCLAMP - TH_HANDLE_FREE + 1,
-	COLOR_NURB_SEL_ULINE_ID,
-	COLOR_ACTIVE_SPLINE,
+	COLOR_NURB_ULINE_ID = TH_HANDLE_AUTOCLAMP - TH_HANDLE_FREE + 2,
 
 	TOT_HANDLE_COL,
 };
@@ -678,10 +675,12 @@ static void curve_batch_cache_create_overlay_batches(Curve *cu)
 						const bool is_active = (i == rdata->actvert);
 						GPU_indexbuf_add_point_vert(&elb, vbo_len_used + 1);
 						for (int j = 0; j < 3; j++) {
-							char vflag = ((&bezt->f1)[j] & SELECT)
-							              ? (is_active ? VFLAG_VERTEX_ACTIVE : VFLAG_VERTEX_SELECTED)
-							              : 0;
+							char vflag = ((&bezt->f1)[j] & SELECT) ? VFLAG_VERTEX_SELECTED : 0;
+							vflag |= (is_active) ? VFLAG_VERTEX_ACTIVE : 0;
 							vflag |= (is_active_nurb) ? ACTIVE_NURB : 0;
+							/* handle color id */
+							char col_id = (&bezt->h1)[j / 2];
+							vflag |= col_id << 3; /* << 3 because of ACTIVE_NURB */
 							GPU_vertbuf_attr_set(vbo, attr_id.pos, vbo_len_used, bezt->vec[j]);
 							GPU_vertbuf_attr_set(vbo, attr_id.data, vbo_len_used, &vflag);
 							vbo_len_used += 1;
@@ -695,10 +694,10 @@ static void curve_batch_cache_create_overlay_batches(Curve *cu)
 				for (const BPoint *bp = nu->bp; a < nu->pntsu; a++, bp++) {
 					if (bp->hide == false) {
 						const bool is_active = (i == rdata->actvert);
-						char vflag = (bp->f1 & SELECT)
-						              ? (is_active ? VFLAG_VERTEX_ACTIVE : VFLAG_VERTEX_SELECTED)
-						              : 0;
+						char vflag = (bp->f1 & SELECT) ? VFLAG_VERTEX_SELECTED : 0;
+						vflag |= (is_active) ? VFLAG_VERTEX_ACTIVE : 0;
 						vflag |= (is_active_nurb) ? ACTIVE_NURB : 0;
+						vflag |= COLOR_NURB_ULINE_ID << 3; /* << 3 because of ACTIVE_NURB */
 						GPU_indexbuf_add_point_vert(&elb, vbo_len_used);
 						GPU_vertbuf_attr_set(vbo, attr_id.pos, vbo_len_used, bp->vec);
 						GPU_vertbuf_attr_set(vbo, attr_id.data, vbo_len_used, &vflag);
@@ -720,78 +719,44 @@ static void curve_batch_cache_create_overlay_batches(Curve *cu)
 	}
 
 
-	if ((cache->overlay.edges == NULL) && (rdata->hide_handles == false)) {
-		/* Note: we could reference indices to vertices (above) */
-
-		static GPUVertFormat format = { 0 };
-		static struct { uint pos, data; } attr_id;
-		if (format.attr_len == 0) {
-			/* initialize vertex format */
-			attr_id.pos = GPU_vertformat_attr_add(&format, "pos", GPU_COMP_F32, 3, GPU_FETCH_FLOAT);
-			attr_id.data = GPU_vertformat_attr_add(&format, "data", GPU_COMP_U8, 1, GPU_FETCH_INT);
-		}
+	if (cache->overlay.edges == NULL) {
+		GPUVertBuf *vbo = cache->overlay.verts->verts[0];
 
-		GPUVertBuf *vbo = GPU_vertbuf_create_with_format(&format);
 		const int edge_len =  curve_render_data_overlay_edges_len_get(rdata);
 		const int vbo_len_capacity = edge_len * 2;
-		int vbo_len_used = 0;
-		GPU_vertbuf_data_alloc(vbo, vbo_len_capacity);
+
+		GPUIndexBufBuilder elb;
+		GPU_indexbuf_init(&elb, GPU_PRIM_LINES, vbo_len_capacity, vbo->vertex_len);
+
+		int curr_index = 0;
 		int i = 0;
 		for (Nurb *nu = rdata->nurbs->first; nu; nu = nu->next, i++) {
-			const bool is_active_nurb = (i == cu->actnu);
-
 			if (nu->bezt) {
 				int a = 0;
 				for (const BezTriple *bezt = nu->bezt; a < nu->pntsu; a++, bezt++) {
 					if (bezt->hide == false) {
-						char col_id;
-
-						for (int j = 0; j < 2; j += 1) {
-							/* same vertex twice, only check different selection */
-							GPU_vertbuf_attr_set(vbo, attr_id.pos, vbo_len_used, bezt->vec[1]);
-							vbo_len_used += 1;
-
-							col_id = (&bezt->h1)[j];
-							if ((&bezt->f1)[j * 2] & SELECT) {
-								col_id += HANDLE_SEL_OFFSET;
-							}
-							if (is_active_nurb) {
-								col_id |= ACTIVE_NURB;
-							}
-
-							GPU_vertbuf_attr_set(vbo, attr_id.pos, vbo_len_used, bezt->vec[j * 2]);
-							GPU_vertbuf_attr_set(vbo, attr_id.data, vbo_len_used, &col_id);
-							vbo_len_used += 1;
-						}
+						GPU_indexbuf_add_line_verts(&elb, curr_index + 1, curr_index + 0);
+						GPU_indexbuf_add_line_verts(&elb, curr_index + 1, curr_index + 2);
+						curr_index += 3;
 					}
 				}
 			}
 			else if (nu->bp) {
+				curr_index += 1;
 				int a = 1;
 				for (const BPoint *bp_prev = nu->bp, *bp_curr = &nu->bp[1]; a < nu->pntsu; a++, bp_prev = bp_curr++) {
-					if ((bp_prev->hide == false) && (bp_curr->hide == false)) {
-						char col_id = ((bp_prev->f1 & SELECT) && (bp_curr->f1 & SELECT)) ? COLOR_NURB_SEL_ULINE_ID : COLOR_NURB_ULINE_ID;
-
-						if (is_active_nurb) {
-							col_id |= ACTIVE_NURB;
+					if (bp_prev->hide == false) {
+						if (bp_curr->hide == false) {
+							GPU_indexbuf_add_line_verts(&elb, curr_index - 1, curr_index + 0);
 						}
-
-						GPU_vertbuf_attr_set(vbo, attr_id.pos, vbo_len_used, bp_prev->vec);
-						vbo_len_used += 1;
-
-						GPU_vertbuf_attr_set(vbo, attr_id.pos, vbo_len_used, bp_curr->vec);
-						GPU_vertbuf_attr_set(vbo, attr_id.data, vbo_len_used, &col_id);
-						vbo_len_used += 1;
-
+						curr_index += 1;
 					}
 				}
 			}
 		}
-		if (vbo_len_capacity != vbo_len_used) {
-			GPU_vertbuf_data_resize(vbo, vbo_len_used);
-		}
 
-		cache->overlay.edges = GPU_batch_create_ex(GPU_PRIM_LINES, vbo, NULL, GPU_BATCH_OWNS_VBO);
+		GPUIndexBuf *ibo = GPU_indexbuf_build(&elb);
+		cache->overlay.edges = GPU_batch_create_ex(GPU_PRIM_LINES, vbo, ibo, GPU_BATCH_OWNS_INDEX);
 	}
 
 	curve_render_data_free(rdata);