Tech ENABLE_GL_CORE_PROFILE - Thick lines shader enhanced to render dashed lines

Fixed conflicts while rebase with master

resources/shaders/140/dashed_thick_lines.fs

@@ -1,19 +1,25 @@
 #version 150
 
 // see as reference: https://github.com/mhalber/Lines/blob/master/geometry_shader_lines.h
+//                   https://stackoverflow.com/questions/52928678/dashed-line-in-opengl3
 
 const vec2 aa_radius = vec2(0.5);
 
+uniform float dash_size;
+uniform float gap_size;
 uniform vec4 uniform_color;
 
 in float line_width;
 in float line_length;
-in vec2 uv;
+in vec3 uvs;
 
 out vec4 out_color;
 
 void main()
 {
+    if (gap_size > 0.0 && fract(uvs.z / (dash_size + gap_size)) > dash_size / (dash_size + gap_size))
+        discard;
+		
 	// We render a quad that is fattened by r, giving total width of the line to be w+r. We want smoothing to happen
 	// around w, so that the edge is properly smoothed out. As such, in the smoothstep function we have:
 	// Far edge   : 1.0                                          = (w+r) / (w+r)
@@ -21,7 +27,7 @@ void main()
 	// This way the smoothing is centered around 'w'.
 
 	out_color = uniform_color;
-	float au = 1.0 - smoothstep(1.0 - (2.0 * aa_radius[0] / line_width),  1.0, abs(uv.x / line_width));
-	float av = 1.0 - smoothstep(1.0 - (2.0 * aa_radius[1] / line_length), 1.0, abs(uv.y / line_length));
+	float au = 1.0 - smoothstep(1.0 - (2.0 * aa_radius[0] / line_width),  1.0, abs(uvs.x / line_width));
+	float av = 1.0 - smoothstep(1.0 - (2.0 * aa_radius[1] / line_length), 1.0, abs(uvs.y / line_length));
 	out_color.a *= min(av, au);
 }

resources/shaders/140/dashed_thick_lines.gs

@@ -1,6 +1,7 @@
 #version 150
 
 // see as reference: https://github.com/mhalber/Lines/blob/master/geometry_shader_lines.h
+//                   https://stackoverflow.com/questions/52928678/dashed-line-in-opengl3
 
 layout(lines) in;
 layout(triangle_strip, max_vertices = 4) out;
@@ -10,9 +11,11 @@ const vec2 aa_radius = vec2(0.5);
 uniform vec2 viewport_size;
 uniform float width;
 
+in float coord_s[];
+
 out float line_width;
 out float line_length;
-out vec2 uv;
+out vec3 uvs;
 
 void main()
 {
@@ -35,19 +38,19 @@ void main()
 	float half_line_width  = 0.5 * line_width;
 	float half_line_length = 0.5 * line_length;
 
-	uv = vec2(-half_line_width, half_line_length);
+	uvs = vec3(-half_line_width, half_line_length, coord_s[0]);
 	gl_Position = vec4((ndc_0 + normal - extension) * gl_in[0].gl_Position.w, gl_in[0].gl_Position.zw);
 	EmitVertex();
 
-	uv = vec2(-half_line_width, -half_line_length);
+	uvs = vec3(-half_line_width, -half_line_length, coord_s[0]);
 	gl_Position = vec4((ndc_0 - normal - extension) * gl_in[0].gl_Position.w, gl_in[0].gl_Position.zw);
 	EmitVertex();
 
-	uv = vec2(half_line_width, half_line_length);
+	uvs = vec3(half_line_width, half_line_length, coord_s[1]);
 	gl_Position = vec4((ndc_1 + normal + extension) * gl_in[1].gl_Position.w, gl_in[1].gl_Position.zw);
 	EmitVertex();
 
-	uv = vec2(half_line_width, -half_line_length);
+	uvs = vec3(half_line_width, -half_line_length, coord_s[1]);
 	gl_Position = vec4((ndc_1 - normal + extension) * gl_in[1].gl_Position.w, gl_in[1].gl_Position.zw);
 	EmitVertex();
 

resources/shaders/140/dashed_thick_lines.vs

@@ -1,13 +1,18 @@
 #version 150
 
 // see as reference: https://github.com/mhalber/Lines/blob/master/geometry_shader_lines.h
+//                   https://stackoverflow.com/questions/52928678/dashed-line-in-opengl3
 
 uniform mat4 view_model_matrix;
 uniform mat4 projection_matrix;
 
-in vec3 v_position;
+// v_position.w = coordinate along the line
+in vec4 v_position;
+
+out float coord_s;
 
 void main()
 {
-    gl_Position = projection_matrix * view_model_matrix * vec4(v_position, 1.0);
+	coord_s = v_position.w;
+    gl_Position = projection_matrix * view_model_matrix * vec4(v_position.xyz, 1.0);
 }