1 files changed, 59 insertions, 0 deletions
diff --git a/source/blender/gpu/shaders/gpu_shader_2D_line_dashed_width_geom.glsl b/source/blender/gpu/shaders/gpu_shader_2D_line_dashed_width_geom.glsl
new file mode 100644
index 00000000000..20c72f4407d
--- /dev/null
+++ b/source/blender/gpu/shaders/gpu_shader_2D_line_dashed_width_geom.glsl
@@ -0,0 +1,59 @@
+
+// Draw dashed lines, perforated in screen space, with non-unary width.
+
+/* Make to be used with dynamic batching so no Model Matrix needed */
+uniform mat4 ModelViewProjectionMatrix;
+uniform vec2 viewport_size;
+
+/* Width of the generated 'line'. */
+uniform float width;  /* in pixels, screen space. */
+
+/* Uniforms from fragment shader, used here to optimize out useless computation in case of solid line. */
+uniform float dash_factor;  /* if > 1.0, solid line. */
+uniform int num_colors;  /* Enabled if > 0, 1 for solid line. */
+
+layout(lines) in;
+
+layout(triangle_strip, max_vertices = 4) out;
+noperspective out float distance_along_line;
+
+void main()
+{
+	vec4 v1 = gl_in[0].gl_Position;
+	vec4 v2 = gl_in[1].gl_Position;
+
+	/* Width, from 2D screen space in pixels, to ModelViewProjection space of each input vertices. */
+	float w1 = (width / viewport_size) * v1.w * 2.0;
+	float w2 = (width / viewport_size) * v2.w * 2.0;
+
+	/* Normalized vector parallel to screen and orthogonal to line. */
+	vec4 wdir = normalize(vec4(v1.y - v2.y, v2.x - v1.x, 0.0, 0.0))
+
+	distance_along_line = 0.0f;
+	gl_Position = v1 + (wdir * w1);
+	EmitVertex();
+
+	gl_Position = v1 - (wdir * w1);
+	EmitVertex();
+
+	if ((num_colors == 1) || (dash_factor >= 1.0f)) {
+		/* Solid line, optimize out distance computation! */
+		distance_along_line = 0.0f;
+	}
+	else {
+		vec2 p1 = (v1.xy / v1.w) * 0.5 + 0.5;  // <- device coordinates in [0..1] range.
+		p1 = p1 * viewport_size;  // <- 'virtual' screen coordinates.
+
+		vec2 p2 = (v2.xy / v2.w) * 0.5 + 0.5;  // <- device coordinates in [0..1] range.
+		p2 = p2 * viewport_size;  // <- 'virtual' screen coordinates.
+
+		distance_along_line = distance(p1, p2);
+	}
+	gl_Position = v2 + (wdir * w2);
+	EmitVertex();
+
+	gl_Position = v2 - (wdir * w2);
+	EmitVertex();
+
+	EndPrimitive();
+}