make line-opacity work with line-image

js: 0e9a86e3553913abb8ebb3d8926e2b99db8d4008

2 files changed, 3 insertions, 1 deletions

diff --git a/src/mbgl/shader/linepattern.fragment.glsl b/src/mbgl/shader/linepattern.fragment.glsl
index 52ca823a3b..45be7c8c2f 100644
--- a/src/mbgl/shader/linepattern.fragment.glsl
+++ b/src/mbgl/shader/linepattern.fragment.glsl
@@ -6,6 +6,7 @@ uniform vec2 u_pattern_size;
 uniform vec2 u_pattern_tl;
 uniform vec2 u_pattern_br;
 uniform float u_fade;
+uniform float u_opacity;
 
 uniform sampler2D u_image;
 
@@ -31,7 +32,7 @@ void main() {
 
     vec4 color = texture2D(u_image, pos) * (1.0 - u_fade) + u_fade * texture2D(u_image, pos2);
 
-    color.rgb *= color.a; // premultiply
+    alpha *= u_opacity;
 
     gl_FragColor = color * alpha;
 }
diff --git a/src/mbgl/shader/linepattern_shader.hpp b/src/mbgl/shader/linepattern_shader.hpp
index ace8198aed..388cff17d2 100644
--- a/src/mbgl/shader/linepattern_shader.hpp
+++ b/src/mbgl/shader/linepattern_shader.hpp
@@ -22,6 +22,7 @@ public:
     Uniform<float>                u_point        = {"u_point",        *this};
     Uniform<float>                u_blur         = {"u_blur",         *this};
     Uniform<float>                u_fade         = {"u_fade",         *this};
+    Uniform<float>                u_opacity      = {"u_opacity",      *this};
 
 private:
     int32_t a_pos = -1;