Immediate Mode: curve draw stroke

How to test this drawing: create and edit a curve and press shift + drag your mouse (or tablet). The Curve needs a Bevel Depth > 0.0.

Note: The ideal solution would be to use a different shader, that takes
no lighting. However according to Clément Foucault there is an assert preventing the same batch to
me used with different attributes (or something like that). Il wait
until the end of such resolution before revisiting this. That said, it
is working fine.

Part of T49043

Differential Revision: https://developer.blender.org/D2501

1 files changed, 24 insertions, 13 deletions

diff --git a/source/blender/editors/curve/editcurve_paint.c b/source/blender/editors/curve/editcurve_paint.c
index 4720b76342c..01d9167cdb7 100644
--- a/source/blender/editors/curve/editcurve_paint.c
+++ b/source/blender/editors/curve/editcurve_paint.c
@@ -48,7 +48,9 @@
 #include "BIF_gl.h"
 #include "BIF_glutil.h"
 
+#include "GPU_batch.h"
 #include "GPU_immediate.h"
+#include "GPU_matrix.h"
 
 #include "curve_intern.h"
 
@@ -467,39 +469,48 @@ static void curve_draw_stroke_3d(const struct bContext *UNUSED(C), ARegion *UNUS
 	Object *obedit = cdd->vc.obedit;
 	Curve *cu = obedit->data;
 
-	UI_ThemeColor(TH_WIRE);
-
 	if (cu->ext2 > 0.0f) {
-		GLUquadricObj *qobj = gluNewQuadric();
-
-		gluQuadricDrawStyle(qobj, GLU_FILL);
-
 		BLI_mempool_iter iter;
 		const struct StrokeElem *selem;
 
 		const float  location_zero[3] = {0};
 		const float *location_prev = location_zero;
 
+		float color[3];
+		UI_GetThemeColor3fv(TH_WIRE, color);
+
+		/* silly light-less shader, non-critical task, so it's fine */
+		float light[3] = {0.0f, 0.0f, 0.0f};
+
+		Batch *sphere = Batch_get_sphere(0);
+		Batch_set_builtin_program(sphere, GPU_SHADER_SIMPLE_LIGHTING);
+		Batch_Uniform3fv(sphere, "color", color);
+		Batch_Uniform3fv(sphere, "light", light);
+
 		/* scale to edit-mode space */
-		glPushMatrix();
-		glMultMatrixf(obedit->obmat);
+		gpuMatrixBegin3D_legacy();
+		gpuPushMatrix();
+		gpuMultMatrix3D(obedit->obmat);
 
 		BLI_mempool_iternew(cdd->stroke_elem_pool, &iter);
 		for (selem = BLI_mempool_iterstep(&iter); selem; selem = BLI_mempool_iterstep(&iter)) {
-			glTranslatef(
+			gpuTranslate3f(
 			        selem->location_local[0] - location_prev[0],
 			        selem->location_local[1] - location_prev[1],
 			        selem->location_local[2] - location_prev[2]);
 			location_prev = selem->location_local;
+
 			const float radius = stroke_elem_radius(cdd, selem);
-			gluSphere(qobj, radius, 12, 8);
+
+			gpuScaleUniform(radius);
+			Batch_draw(sphere);
+			gpuScaleUniform(1.0f / radius);
 
 			location_prev = selem->location_local;
 		}
 
-		glPopMatrix();
-
-		gluDeleteQuadric(qobj);
+		gpuPopMatrix();
+		gpuMatrixEnd();
 	}
 
 	if (stroke_len > 1) {