Merge lp:~vanvugt/mir/neg into lp:mir

[Daniel van Vugt]

First attempts at adding custom shaders in shells. As an example, this
introduces negative (Super+N) and high contrast (Super+C) modes to the
demo shell (mir_proving_server). (LP: #1400580)

I also took the opportunity to clean up and eliminate the ugly vector
of programs approach.

[PS Jenkins bot (ps-jenkins)]

FAILED: Continuous integration, rev:2224
http://jenkins.qa.ubuntu.com/job/mir-ci/2611/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-android-vivid-i386-build/790
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-clang-vivid-amd64-build/790
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-vivid-touch/752
    FAILURE: http://jenkins.qa.ubuntu.com/job/mir-vivid-amd64-ci/608/console
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-builder-vivid-armhf/752
        deb: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-builder-vivid-armhf/752/artifact/work/output/*zip*/output.zip
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review: Needs Fixing (continuous-integration)

[PS Jenkins bot (ps-jenkins)]

PASSED: Continuous integration, rev:2226
http://jenkins.qa.ubuntu.com/job/mir-ci/2613/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-android-vivid-i386-build/793
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-clang-vivid-amd64-build/793
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-vivid-touch/755
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-vivid-amd64-ci/610
        deb: http://jenkins.qa.ubuntu.com/job/mir-vivid-amd64-ci/610/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-builder-vivid-armhf/755
        deb: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-builder-vivid-armhf/755/artifact/work/output/*zip*/output.zip
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review: Approve (continuous-integration)

[Andreas Pokorny (andreas-pokorny)]

Looking at multiwin, I believe you need to apply contrast only on .rgb and leave alpha as is .. or maybe apply it to .rgb/.alpha and *.alpha afterwards, but not sure about the constrast computation.

+ 133 neffects - because of negative inside that MP I stumbled over that term.

Havent thought about the changes to GLRenderer yet.

review: Needs Fixing

[Kevin DuBois (kdub)]

Unity8 reimplements GLRenderer, so they wouldn't want to pick up our GLRenderer just to have the inverted color rendering. USC doesn't reimplement GLRenderer, but if we're not publishing the header, then this wouldn't help USC either. I'm okay with this change to the proving shell (although, why not try to drive through the public api?), but how does this help USC/U8 implement the feature?

review: Needs Information

[Daniel van Vugt (vanvugt)]

This proposal is not intended to help USC or U8 in their current forms. It's foundational work to demo and support future custom shaders in custom shells that utilize GLRenderer. Which is why I did it on the weekend.

There are many such enhancements I want to see in Mir. And any that are not business driven will be done in my own time. Just as you would see from any community contributor.

[PS Jenkins bot (ps-jenkins)]

PASSED: Continuous integration, rev:2227
http://jenkins.qa.ubuntu.com/job/mir-ci/2627/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-android-vivid-i386-build/816
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-clang-vivid-amd64-build/816
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-vivid-touch/778
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-vivid-amd64-ci/624
        deb: http://jenkins.qa.ubuntu.com/job/mir-vivid-amd64-ci/624/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-builder-vivid-armhf/778
        deb: http://jenkins.qa.ubuntu.com/job/mir-mediumtests-builder-vivid-armhf/778/artifact/work/output/*zip*/output.zip
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    SUCCESS: http://s-jenkins.ubuntu-ci:8080/job/touch-flash-device/17021

Click here to trigger a rebuild:
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review: Approve (continuous-integration)

[Andreas Pokorny (andreas-pokorny)]

yes looks better.. abstain for now until I get look at the GLRenderer solution again

review: Abstain

[Kevin DuBois (kdub)]

I don't have a problem with adding the feature, but I guess I still don't see how adding a feature that USC/U8 cannot use helps with the bug. To rephrase, I don't see this addressing the bug. Is this just proving that a shader can be written to achieve the effect that is requested? (making this a somewhat-related branch, but not a fix to the wishlist request)

[Daniel van Vugt (vanvugt)]

For me this branch has a more important purpose than the attached bug; It provides a simple demo for custom shaders in custom shells. It showed me what still needed improving in GLRenderer, so that I may get to my own goal of demonstrating more fancy decoration ideas in the demo shell. I then plan to use those demonstrations to argue for similar ideas in future for Unity8.

[Daniel van Vugt (vanvugt)]

So the purpose of our demos should come full circle, from appearing to be toys, but eventually helping to motivate positive change in real projects.

[Robert Carr (robertcarr)]

Should at least be unlinked from bug.

[Kevin DuBois (kdub)]

> Should at least be unlinked from bug.
Well, it shouldn't resolve the bug at least (could be in the comments)

[Kevin DuBois (kdub)]

> So the purpose of our demos should come full circle, from appearing to be
> toys, but eventually helping to motivate positive change in real projects.

I agree, but we're changing mg::Renderer (a non-public interface, because its too strange of an interface to support publicly) So, I guess I'm on-board with the feature, but would rather start driving the public interfaces, as opposed to the privileged internal access that the playground/ servers have.

[Cemil Azizoglu (cemil-azizoglu)]

+1 on not resolving the bug.

Otherwise, it looks fine.

review: Approve

[Daniel van Vugt (vanvugt)]

This branch doesn't resolve the bug for Unity8. That's why it's a separate task already.

=== modified file 'doc/demo_shell_controls.md'
--- doc/demo_shell_controls.md	2014-12-19 02:31:34 +0000
+++ doc/demo_shell_controls.md	2015-01-13 03:37:28 +0000
@@ -36,6 +36,8 @@
  - Switch apps: *Alt-Tab* or *4-finger swipe left/right*
  - Move window: *Alt-leftmousebutton* or *3-finger drag*
  - Resize window: *Alt-middlemousebutton* or *3-finger pinch/zoom*
+ - Toggle negative rendering: *Super-N*
+ - Toggle high-contrast rendering: *Super-C*
  - Sleep/wake all displays: *Alt-P* or *Android power button*
  - Rotate the focussed monitor: *Ctrl-Alt-(Left/Right/Up/Down)* or
    *Volume up/down while touching the screen*

=== modified file 'playground/demo-shell/demo_compositor.cpp'
--- playground/demo-shell/demo_compositor.cpp	2015-01-03 10:01:42 +0000
+++ playground/demo-shell/demo_compositor.cpp	2015-01-13 03:37:28 +0000
@@ -161,6 +161,11 @@
     update_viewport();
 }
 
+void me::DemoCompositor::set_colour_effect(me::ColourEffect e)
+{
+    renderer.set_colour_effect(e);
+}
+
 void me::DemoCompositor::update_viewport()
 {
     auto const& view_area = display_buffer.view_area();

=== modified file 'playground/demo-shell/demo_compositor.h'
--- playground/demo-shell/demo_compositor.h	2015-01-03 10:01:42 +0000
+++ playground/demo-shell/demo_compositor.h	2015-01-13 03:37:28 +0000
@@ -55,6 +55,8 @@
     void zoom(float mag);
     void on_cursor_movement(geometry::Point const& p);
 
+    void set_colour_effect(ColourEffect);
+
     static void for_each(std::function<void(DemoCompositor&)> f);
 
 private:

=== modified file 'playground/demo-shell/demo_renderer.cpp'
--- playground/demo-shell/demo_renderer.cpp	2015-01-03 10:01:42 +0000
+++ playground/demo-shell/demo_renderer.cpp	2015-01-13 03:37:28 +0000
@@ -25,6 +25,7 @@
 using namespace mir;
 using namespace mir::examples;
 using namespace mir::geometry;
+using namespace mir::compositor;
 
 namespace
 {
@@ -143,6 +144,31 @@
     return corner;
 }
 
+static const GLchar inverse_fshader[] =
+{
+    "precision mediump float;\n"
+    "uniform sampler2D tex;\n"
+    "uniform float alpha;\n"
+    "varying vec2 v_texcoord;\n"
+    "void main() {\n"
+    "    vec4 f = texture2D(tex, v_texcoord);\n"
+    "    vec3 inverted = (vec3(1.0) - (f.rgb / f.a)) * f.a;\n"
+    "    gl_FragColor = alpha*vec4(inverted, f.a);\n"
+    "}\n"
+};
+static const GLchar contrast_fshader[] =
+{
+    "precision mediump float;\n"
+    "uniform sampler2D tex;\n"
+    "uniform float alpha;\n"
+    "varying vec2 v_texcoord;\n"
+    "void main() {\n"
+    "    vec4 raw = texture2D(tex, v_texcoord);\n"
+    "    vec3 bent = (1.0 - cos(raw.rgb * 3.141592654)) / 2.0;\n"
+    "    gl_FragColor = alpha * vec4(bent, raw.a);\n"
+    "}\n"
+};
+
 } // namespace
 
 DemoRenderer::DemoRenderer(
@@ -156,7 +182,10 @@
         dest_alpha),
     titlebar_height{titlebar_height},
     shadow_radius{shadow_radius},
-    corner_radius{0.5f}
+    corner_radius{0.5f},
+    colour_effect{none},
+    inverse_program(family.add_program(vshader, inverse_fshader)),
+    contrast_program(family.add_program(vshader, contrast_fshader))
 {
     shadow_corner_tex = generate_shadow_corner_texture(0.4f);
     titlebar_corner_tex = generate_frame_corner_texture(corner_radius,
@@ -338,3 +367,21 @@
             display_area.overlaps(top) ||
             display_area.overlaps(bottom));
 }
+
+void DemoRenderer::set_colour_effect(ColourEffect e)
+{
+    colour_effect = e;
+}
+
+void DemoRenderer::draw(graphics::Renderable const& renderable,
+                        GLRenderer::Program const& current_program) const
+{
+    const GLRenderer::Program* const programs[ColourEffect::neffects] =
+    {
+        &current_program,
+        &inverse_program,
+        &contrast_program
+    };
+
+    GLRenderer::draw(renderable, *programs[colour_effect]);
+}

=== modified file 'playground/demo-shell/demo_renderer.h'
--- playground/demo-shell/demo_renderer.h	2015-01-03 10:01:42 +0000
+++ playground/demo-shell/demo_renderer.h	2015-01-13 03:37:28 +0000
@@ -28,6 +28,14 @@
 namespace examples
 {
 
+enum ColourEffect
+{
+    none,
+    inverse,
+    contrast,
+    neffects
+};
+
 class DemoRenderer : public compositor::GLRenderer
 {
 public:
@@ -40,9 +48,20 @@
 
     void begin(std::unordered_set<graphics::Renderable::ID> renderables_not_to_decorate) const;
     
-    void tessellate(
-        std::vector<graphics::GLPrimitive>& primitives,
-        graphics::Renderable const& renderable) const override;
+    bool would_embellish(
+        graphics::Renderable const& renderable,
+        geometry::Rectangle const&) const;
+
+    void set_colour_effect(ColourEffect);
+
+protected:
+    void tessellate(std::vector<graphics::GLPrimitive>& primitives,
+                    graphics::Renderable const& renderable) const override;
+
+    void draw(graphics::Renderable const& renderable,
+              GLRenderer::Program const& prog) const override;
+
+private:
     void tessellate_shadow(
         std::vector<graphics::GLPrimitive>& primitives,
         graphics::Renderable const& renderable,
@@ -51,16 +70,15 @@
         std::vector<graphics::GLPrimitive>& primitives,
         graphics::Renderable const& renderable,
         float titlebar_height) const;
-    bool would_embellish(
-        graphics::Renderable const& renderable,
-        geometry::Rectangle const&) const;
 
-private:
     float const titlebar_height;
     float const shadow_radius;
     float const corner_radius;
     GLuint shadow_corner_tex;
     GLuint titlebar_corner_tex;
+
+    ColourEffect colour_effect;
+    Program inverse_program, contrast_program;
     
     mutable std::unordered_set<graphics::Renderable::ID> decoration_skip_list;
 };

=== modified file 'playground/demo-shell/window_manager.cpp'
--- playground/demo-shell/window_manager.cpp	2014-12-19 02:31:34 +0000
+++ playground/demo-shell/window_manager.cpp	2015-01-13 03:37:28 +0000
@@ -128,6 +128,17 @@
 
 } // namespace
 
+
+void me::WindowManager::toggle(ColourEffect which)
+{
+    colour_effect = (colour_effect == which) ? none : which;
+    me::DemoCompositor::for_each([this](me::DemoCompositor& c)
+    {
+        c.set_colour_effect(colour_effect);
+    });
+    force_redraw();
+}
+
 bool me::WindowManager::handle(MirEvent const& event)
 {
     // TODO: Fix android configuration and remove static hack ~racarr
@@ -276,6 +287,16 @@
             compositor->start();
             return true;
         }
+        else if (event.key.modifiers & mir_key_modifier_meta &&
+                 event.key.scan_code == KEY_N)
+        {
+            toggle(inverse);
+        }
+        else if (event.key.modifiers & mir_key_modifier_meta &&
+                 event.key.scan_code == KEY_C)
+        {
+            toggle(contrast);
+        }
     }
     else if (event.type == mir_event_type_motion &&
              focus_controller)

=== modified file 'playground/demo-shell/window_manager.h'
--- playground/demo-shell/window_manager.h	2014-12-19 02:31:34 +0000
+++ playground/demo-shell/window_manager.h	2015-01-13 03:37:28 +0000
@@ -23,6 +23,7 @@
 #include "mir/input/scene.h"
 #include "mir/geometry/displacement.h"
 #include "mir/geometry/size.h"
+#include "demo_renderer.h"
 
 #include <memory>
 
@@ -74,6 +75,9 @@
     float old_pinch_diam;
     int max_fingers;  // Maximum number of fingers touched during gesture
     int zoom_exponent = 0;
+    ColourEffect colour_effect = none;
+
+    void toggle(ColourEffect);
 };
 
 }

=== modified file 'src/include/server/mir/compositor/gl_renderer.h'
--- src/include/server/mir/compositor/gl_renderer.h	2015-01-05 03:23:16 +0000
+++ src/include/server/mir/compositor/gl_renderer.h	2015-01-13 03:37:28 +0000
@@ -74,12 +74,12 @@
     virtual void tessellate(std::vector<graphics::GLPrimitive>& primitives,
                             graphics::Renderable const& renderable) const;
 
-    virtual void render(graphics::Renderable const& renderable) const;
-
     DestinationAlpha destination_alpha() const;
 
     GLfloat clear_color[4];
 
+    mutable long long frameno = 0;
+
     GLProgramFamily family;
     struct Program
     {
@@ -92,16 +92,25 @@
        GLint transform_uniform = -1;
        GLint screen_to_gl_coords_uniform = -1;
        GLint alpha_uniform = -1;
+       mutable long long last_used_frameno = 0;
 
        Program(GLuint program_id);
     };
-    std::vector<Program> programs;
+    Program default_program, alpha_program;
+
+    static const GLchar* const vshader;
+    static const GLchar* const default_fshader;
+    static const GLchar* const alpha_fshader;
+
+    virtual void draw(graphics::Renderable const& renderable,
+                      GLRenderer::Program const& prog) const;
 
 private:
     std::unique_ptr<graphics::GLTextureCache> mutable texture_cache;
     float rotation;
     DestinationAlpha const dest_alpha;
     geometry::Rectangle viewport;
+    glm::mat4 screen_to_gl_coords, screen_rotation;
 
     std::vector<graphics::GLPrimitive> mutable primitives;
 };

=== modified file 'src/server/compositor/gl_renderer.cpp'
--- src/server/compositor/gl_renderer.cpp	2015-01-05 03:23:16 +0000
+++ src/server/compositor/gl_renderer.cpp	2015-01-13 03:37:28 +0000
@@ -38,16 +38,7 @@
 namespace mc = mir::compositor;
 namespace geom = mir::geometry;
 
-namespace
-{
-
-enum
-{
-    default_program_index = 0,
-    alpha_program_index = 1
-};
-
-const GLchar vshader[] =
+const GLchar* const mc::GLRenderer::vshader =
 {
     "attribute vec3 position;\n"
     "attribute vec2 texcoord;\n"
@@ -64,7 +55,7 @@
     "}\n"
 };
 
-const GLchar alpha_fshader[] =
+const GLchar* const mc::GLRenderer::alpha_fshader =
 {
     "precision mediump float;\n"
     "uniform sampler2D tex;\n"
@@ -76,8 +67,8 @@
     "}\n"
 };
 
-const GLchar default_fshader[] =  // Should be faster than blending in theory
-{
+const GLchar* const mc::GLRenderer::default_fshader =
+{   // This is the fastest fragment shader. Use it when you can.
     "precision mediump float;\n"
     "uniform sampler2D tex;\n"
     "varying vec2 v_texcoord;\n"
@@ -86,8 +77,6 @@
     "}\n"
 };
 
-}
-
 mc::GLRenderer::Program::Program(GLuint program_id)
 {
     id = program_id;
@@ -106,8 +95,8 @@
     geom::Rectangle const& display_area,
     DestinationAlpha dest_alpha)
     : clear_color{0.0f, 0.0f, 0.0f, 1.0f},
-      programs{family.add_program(vshader, default_fshader),
-               family.add_program(vshader, alpha_fshader)},
+      default_program(family.add_program(vshader, default_fshader)),
+      alpha_program(family.add_program(vshader, alpha_fshader)),
       texture_cache(std::move(texture_cache)),
       rotation(NAN), // ensure the first set_rotation succeeds
       dest_alpha(dest_alpha)
@@ -127,14 +116,7 @@
         mir::log_info("%s: %s", s.label, val);
     }
 
-    for (auto& p : programs)
-    {
-        glUseProgram(p.id);
-        glUniform1i(p.tex_uniform, 0);
-    }
-
     glBindBuffer(GL_ARRAY_BUFFER, 0);
-    glUseProgram(0);
 
     set_viewport(display_area);
     set_rotation(0.0f);
@@ -159,23 +141,17 @@
     if (dest_alpha == DestinationAlpha::opaque)
         glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_FALSE);
 
+    ++frameno;
     for (auto const& r : renderables)
-        render(*r);
+        draw(*r, r->alpha() < 1.0f ? alpha_program : default_program);
 
     texture_cache->drop_unused();
 }
 
-void mc::GLRenderer::render(mg::Renderable const& renderable) const
+void mc::GLRenderer::draw(mg::Renderable const& renderable,
+                          GLRenderer::Program const& prog) const
 {
-    const Program* prog = &programs[default_program_index];
-
-    if (renderable.alpha() < 1.0f)
-    {
-        prog = &programs[alpha_program_index];
-        glEnable(GL_BLEND);
-        glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
-    }
-    else if (renderable.shaped())
+    if (renderable.alpha() < 1.0f || renderable.shaped())
     {
         glEnable(GL_BLEND);
         glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
@@ -185,7 +161,17 @@
         glDisable(GL_BLEND);
     }
 
-    glUseProgram(prog->id);
+    glUseProgram(prog.id);
+    if (prog.last_used_frameno != frameno)
+    {   // Avoid reloading the screen-global uniforms on every renderable
+        prog.last_used_frameno = frameno;
+        glUniform1i(prog.tex_uniform, 0);
+        glUniformMatrix4fv(prog.display_transform_uniform, 1, GL_FALSE,
+                           glm::value_ptr(screen_rotation));
+        glUniformMatrix4fv(prog.screen_to_gl_coords_uniform, 1, GL_FALSE,
+                           glm::value_ptr(screen_to_gl_coords));
+    }
+
     glActiveTexture(GL_TEXTURE0);
 
     auto const& rect = renderable.screen_position();
@@ -193,17 +179,17 @@
                       rect.size.width.as_int() / 2.0f;
     GLfloat centrey = rect.top_left.y.as_int() +
                       rect.size.height.as_int() / 2.0f;
-    glUniform2f(prog->centre_uniform, centrex, centrey);
+    glUniform2f(prog.centre_uniform, centrex, centrey);
 
-    glUniformMatrix4fv(prog->transform_uniform, 1, GL_FALSE,
+    glUniformMatrix4fv(prog.transform_uniform, 1, GL_FALSE,
                        glm::value_ptr(renderable.transformation()));
 
-    if (prog->alpha_uniform >= 0)
-        glUniform1f(prog->alpha_uniform, renderable.alpha());
+    if (prog.alpha_uniform >= 0)
+        glUniform1f(prog.alpha_uniform, renderable.alpha());
 
     /* Draw */
-    glEnableVertexAttribArray(prog->position_attr);
-    glEnableVertexAttribArray(prog->texcoord_attr);
+    glEnableVertexAttribArray(prog.position_attr);
+    glEnableVertexAttribArray(prog.texcoord_attr);
 
     primitives.clear();
     tessellate(primitives, renderable);
@@ -220,18 +206,18 @@
         else
             surface_tex->bind();
 
-        glVertexAttribPointer(prog->position_attr, 3, GL_FLOAT,
+        glVertexAttribPointer(prog.position_attr, 3, GL_FLOAT,
                               GL_FALSE, sizeof(mg::GLVertex),
                               &p.vertices[0].position);
-        glVertexAttribPointer(prog->texcoord_attr, 2, GL_FLOAT,
+        glVertexAttribPointer(prog.texcoord_attr, 2, GL_FLOAT,
                               GL_FALSE, sizeof(mg::GLVertex),
                               &p.vertices[0].texcoord);
 
         glDrawArrays(p.type, 0, p.nvertices);
     }
 
-    glDisableVertexAttribArray(prog->texcoord_attr);
-    glDisableVertexAttribArray(prog->position_attr);
+    glDisableVertexAttribArray(prog.texcoord_attr);
+    glDisableVertexAttribArray(prog.position_attr);
 }
 
 void mc::GLRenderer::set_viewport(geometry::Rectangle const& rect)
@@ -245,7 +231,7 @@
      * (top-left is (0,0), bottom-right is (W,H)) to the normalized GL coordinate system
      * (top-left is (-1,1), bottom-right is (1,-1))
      */
-    glm::mat4 screen_to_gl_coords = glm::translate(glm::mat4(1.0f), glm::vec3{-1.0f, 1.0f, 0.0f});
+    screen_to_gl_coords = glm::translate(glm::mat4(1.0f), glm::vec3{-1.0f, 1.0f, 0.0f});
 
     /*
      * Perspective division is one thing that can't be done in a matrix
@@ -270,14 +256,6 @@
                       -rect.top_left.y.as_float(),
                       0.0f});
 
-    for (auto& p : programs)
-    {
-        glUseProgram(p.id);
-        glUniformMatrix4fv(p.screen_to_gl_coords_uniform, 1, GL_FALSE,
-                           glm::value_ptr(screen_to_gl_coords));
-    }
-    glUseProgram(0);
-
     viewport = rect;
 }
 
@@ -289,18 +267,11 @@
     float rad = degrees * M_PI / 180.0f;
     GLfloat cos = cosf(rad);
     GLfloat sin = sinf(rad);
-    GLfloat rot[16] = {cos,  sin,  0.0f, 0.0f,
+    screen_rotation = {cos,  sin,  0.0f, 0.0f,
                        -sin, cos,  0.0f, 0.0f,
                        0.0f, 0.0f, 1.0f, 0.0f,
                        0.0f, 0.0f, 0.0f, 1.0f};
 
-    for (auto& p : programs)
-    {
-        glUseProgram(p.id);
-        glUniformMatrix4fv(p.display_transform_uniform, 1, GL_FALSE, rot);
-    }
-    glUseProgram(0);
-
     rotation = degrees;
 }
 

=== modified file 'src/server/symbols.map'
--- src/server/symbols.map	2015-01-03 09:28:20 +0000
+++ src/server/symbols.map	2015-01-13 03:37:28 +0000
@@ -787,10 +787,19 @@
     mir::compositor::GLRenderer::set_viewport*;
     mir::compositor::GLRenderer::suspend*;
     mir::compositor::GLRenderer::tessellate*;
-    mir::compositor::GLProgramFamily::*;
     typeinfo?for?mir::compositor::GLRenderer;
     vtable?for?mir::compositor::GLRenderer;
     vtable?for?mir::compositor::RecentlyUsedCache;
   };
  local: *;
 };
+
+MIR_SERVER_28.1 {
+ global:
+  extern "C++" {
+    mir::compositor::GLRenderer::draw*;
+    mir::compositor::GLRenderer::vshader;
+    mir::compositor::GLRenderer::Program::Program*;
+    mir::compositor::GLProgramFamily::*;
+  };
+} MIR_SERVER_28;