Reworked version of dashed line shader.

Using geometry shader allows us to get rid of the 'line origin' extra
vertex attribute, which means dashed shader no longer requires fiddling
with those vertex attributes definition, and, most importantly, does not
require anymore special drawing code!

As you can see, this makes code much simpler, and much less verbose,
especially in complex cases.

In addition, changed how dashes are handled, to have two 'modes', a
simple one with single color (using default "color" uniform name), and a
more advanced one allowing more complex and multi-color patterns.

Note that since GLSL 1.2 does not support geometry shaders, a hack was
added for now (which gives solid lines, but at least does not make
Blender crash).

1 files changed, 8 insertions, 19 deletions

diff --git a/source/blender/editors/space_sequencer/sequencer_draw.c b/source/blender/editors/space_sequencer/sequencer_draw.c
index 6a9437bb892..e7c7b3d67b9 100644
--- a/source/blender/editors/space_sequencer/sequencer_draw.c
+++ b/source/blender/editors/space_sequencer/sequencer_draw.c
@@ -1033,13 +1033,7 @@ static void sequencer_draw_borders(const SpaceSeq *sseq, const View2D *v2d, cons
 	glLineWidth(1.0f);
 
 	/* border */
-	VertexFormat *format = immVertexFormat();
-	unsigned int pos = VertexFormat_add_attrib(format, "pos", COMP_F32, 2, KEEP_FLOAT);
-	unsigned int line_origin = VertexFormat_add_attrib(format, "line_origin", COMP_F32, 2, KEEP_FLOAT);
-	float color1[4];
-
-	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-	glEnable(GL_BLEND);
+	const uint shdr_pos = VertexFormat_add_attrib(immVertexFormat(), "pos", COMP_F32, 2, KEEP_FLOAT);
 
 	immBindBuiltinProgram(GPU_SHADER_2D_LINE_DASHED_COLOR);
 
@@ -1047,36 +1041,31 @@ static void sequencer_draw_borders(const SpaceSeq *sseq, const View2D *v2d, cons
 	glGetFloatv(GL_VIEWPORT, viewport_size);
 	immUniform2f("viewport_size", viewport_size[2] / UI_DPI_FAC, viewport_size[3] / UI_DPI_FAC);
 
-	UI_GetThemeColor4fv(TH_BACK, color1);
-	immUniform4fv("color1", color1);
-	immUniform4f("color2", 0.0f, 0.0f, 0.0f, 0.0f);
+	immUniformThemeColor(TH_BACK);
+	immUniform1i("num_colors", 0);  /* Simple dashes. */
 	immUniform1f("dash_width", 6.0f);
-	immUniform1f("dash_width_on", 3.0f);
+	immUniform1f("dash_factor", 0.5f);
 
-	imm_draw_line_box_dashed(pos, line_origin, x1 - 0.5f, y1 - 0.5f, x2 + 0.5f, y2 + 0.5f);
+	imm_draw_line_box(shdr_pos, x1 - 0.5f, y1 - 0.5f, x2 + 0.5f, y2 + 0.5f);
 
 	/* safety border */
 	if (sseq->flag & SEQ_SHOW_SAFE_MARGINS) {
-		UI_GetThemeColorBlend3f(TH_VIEW_OVERLAY, TH_BACK, 0.25f, color1);
-		color1[3] = 1.0f;
-		immUniform4fv("color1", color1);
+		immUniformThemeColorBlend(TH_VIEW_OVERLAY, TH_BACK, 0.25f);
 
 		UI_draw_safe_areas(
-		        pos, line_origin, x1, x2, y1, y2,
+		        shdr_pos, x1, x2, y1, y2,
 		        scene->safe_areas.title,
 		        scene->safe_areas.action);
 
 		if (sseq->flag & SEQ_SHOW_SAFE_CENTER) {
 			UI_draw_safe_areas(
-			        pos, line_origin, x1, x2, y1, y2,
+			        shdr_pos, x1, x2, y1, y2,
 			        scene->safe_areas.title_center,
 			        scene->safe_areas.action_center);
 		}
 	}
 
 	immUnbindProgram();
-
-	glDisable(GL_BLEND);
 }
 
 /* draws checkerboard background for transparent content */