1 files changed, 82 insertions, 0 deletions
diff --git a/source/blender/draw/engines/gpencil/shaders/gpencil_point_geom.glsl b/source/blender/draw/engines/gpencil/shaders/gpencil_point_geom.glsl
new file mode 100644
index 00000000000..f092149430c
--- /dev/null
+++ b/source/blender/draw/engines/gpencil/shaders/gpencil_point_geom.glsl
@@ -0,0 +1,82 @@
+uniform mat4 ModelViewProjectionMatrix;
+uniform vec2 Viewport;
+uniform int xraymode;
+
+layout(points) in;
+layout(triangle_strip, max_vertices = 4) out;
+
+in vec4 finalColor[1];
+in float finalThickness[1];
+in vec2 finaluvdata[1];
+
+out vec4 mColor;
+out vec2 mTexCoord;
+
+#define GP_XRAY_FRONT 0
+#define GP_XRAY_3DSPACE 1
+#define GP_XRAY_BACK  2
+
+/* project 3d point to 2d on screen space */
+vec2 toScreenSpace(vec4 vertex)
+{
+	return vec2(vertex.xy / vertex.w) * Viewport;
+}
+
+/* get zdepth value */
+float getZdepth(vec4 point)
+{
+	if (xraymode == GP_XRAY_FRONT) {
+		return 0.0;
+	}
+	if (xraymode == GP_XRAY_3DSPACE) {
+		return (point.z / point.w);
+	}
+	if  (xraymode == GP_XRAY_BACK) {
+		return 0.999999;
+	}
+
+	/* in front by default */
+	return 0.0;
+}
+
+vec2 rotateUV(vec2 uv, float angle)
+{
+	/* translate center of rotation to the center of texture */
+	vec2 new_uv = uv - vec2(0.5f, 0.5f);
+	vec2 rot_uv;
+	rot_uv.x = new_uv.x * cos(angle) - new_uv.y * sin(angle);
+	rot_uv.y = new_uv.y * cos(angle) + new_uv.x * sin(angle);
+	return rot_uv + vec2(0.5f, 0.5f);
+}
+
+void main(void)
+{
+	/* receive 4 points */
+	vec4 P0 = gl_in[0].gl_Position;
+	vec2 sp0 = toScreenSpace(P0);
+
+	float size = finalThickness[0];
+	float aspect = 1.0;
+	/* generate the triangle strip */
+	mTexCoord = rotateUV(vec2(0, 1), finaluvdata[0].y);
+	mColor = finalColor[0];
+	gl_Position = vec4(vec2(sp0.x - size, sp0.y + size * aspect) / Viewport, getZdepth(P0), 1.0);
+	EmitVertex();
+
+	mTexCoord = rotateUV(vec2(0, 0), finaluvdata[0].y);
+	mColor = finalColor[0];
+	gl_Position = vec4(vec2(sp0.x - size, sp0.y - size * aspect) / Viewport, getZdepth(P0), 1.0);
+	EmitVertex();
+
+	mTexCoord = rotateUV(vec2(1, 1), finaluvdata[0].y);
+	mColor = finalColor[0];
+	gl_Position = vec4(vec2(sp0.x + size, sp0.y + size * aspect) / Viewport, getZdepth(P0), 1.0);
+	EmitVertex();
+
+	mTexCoord = rotateUV(vec2(1, 0), finaluvdata[0].y);
+	mColor = finalColor[0];
+	gl_Position = vec4(vec2(sp0.x + size, sp0.y - size * aspect) / Viewport, getZdepth(P0), 1.0);
+	EmitVertex();
+
+	EndPrimitive();
+}