Gl context loss (#1234)

* Remove generation tracking code

Rebuild valid framebuffer selection on context loss

* Request GLSurfaceView to preserve EGL context on pause

android/tangram/src/main/cpp/platform_android.cpp

@@ -204,8 +204,6 @@ std::vector<FontSourceHandle> systemFontFallbacksHandle() {
     std::string fallbackPath = fontFallbackPath(importance, weightHint);
 
     while (!fallbackPath.empty()) {
-        LOG("Loading font %s", fallbackPath.c_str());
-
         handles.emplace_back(fallbackPath);
 
         fallbackPath = fontFallbackPath(importance++, weightHint);

android/tangram/src/main/java/com/mapzen/tangram/MapController.java

@@ -172,6 +172,7 @@ protected MapController(GLSurfaceView view) {
         mapView = view;
         view.setRenderer(this);
         view.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
+        view.setPreserveEGLContextOnPause(true);
 
         // Set a default HTTPHandler
         httpHandler = new HttpHandler();
@@ -251,7 +252,6 @@ public void loadSceneFile(String path) {
      * @param sceneUpdates List of {@code SceneUpdate}
      */
     public void loadSceneFile(String path, List<SceneUpdate> sceneUpdates) {
-
         String[] updateStrings = bundleSceneUpdates(sceneUpdates);
         scenePath = path;
         checkPointer(mapPointer);

core/src/gl/dynamicQuadMesh.h

@@ -81,8 +81,6 @@ void DynamicQuadMesh<T>::upload(RenderState& rs) {
 
     if (m_nVertices == 0 || m_isUploaded) { return; }
 
-    MeshBase::checkValidity(rs);
-
     // Generate vertex buffer, if needed
     if (m_glVertexBuffer == 0) {
         GL::genBuffers(1, &m_glVertexBuffer);

core/src/gl/framebuffer.cpp

@@ -12,7 +12,6 @@ namespace Tangram {
 
 FrameBuffer::FrameBuffer(int _width, int _height, bool _colorRenderBuffer) :
     m_glFrameBufferHandle(0),
-    m_generation(-1),
     m_valid(false),
     m_colorRenderBuffer(_colorRenderBuffer),
     m_width(_width), m_height(_height) {
@@ -145,22 +144,17 @@ void FrameBuffer::init(RenderState& _rs) {
         m_valid = true;
     }
 
-    m_generation = _rs.generation();
-
     m_disposer = Disposer(_rs);
 }
 
 FrameBuffer::~FrameBuffer() {
 
-    int generation = m_generation;
     GLuint glHandle = m_glFrameBufferHandle;
 
     m_disposer([=](RenderState& rs) {
-        if (rs.isValidGeneration(generation)) {
-            rs.framebufferUnset(glHandle);
+        rs.framebufferUnset(glHandle);
 
-            GL::deleteFramebuffers(1, &glHandle);
-        }
+        GL::deleteFramebuffers(1, &glHandle);
     });
 }
 

core/src/gl/framebuffer.h

@@ -49,8 +49,6 @@ class FrameBuffer {
 
     GLuint m_glColorRenderBufferHandle;
 
-    int m_generation;
-
     bool m_valid;
 
     bool m_colorRenderBuffer;

core/src/gl/mesh.cpp

@@ -22,8 +22,6 @@ MeshBase::MeshBase() {
     m_dirty = false;
     m_isUploaded = false;
     m_isCompiled = false;
-
-    m_generation = -1;
 }
 
 MeshBase::MeshBase(std::shared_ptr<VertexLayout> _vertexLayout, GLenum _drawMode, GLenum _hint)
@@ -38,24 +36,21 @@ MeshBase::MeshBase(std::shared_ptr<VertexLayout> _vertexLayout, GLenum _drawMode
 MeshBase::~MeshBase() {
 
     auto vaos = m_vaos;
-    auto generation = m_generation;
     auto glVertexBuffer = m_glVertexBuffer;
     auto glIndexBuffer = m_glIndexBuffer;
 
     m_disposer([=](RenderState& rs) mutable {
         // Deleting a index/array buffer being used ends up setting up the current vertex/index buffer to 0
         // after the driver finishes using it, force the render state to be 0 for vertex/index buffer
-        if (rs.isValidGeneration(generation)) {
-            if (glVertexBuffer) {
-                rs.vertexBufferUnset(glVertexBuffer);
-                GL::deleteBuffers(1, &glVertexBuffer);
-            }
-            if (glIndexBuffer) {
-                rs.indexBufferUnset(glIndexBuffer);
-                GL::deleteBuffers(1, &glIndexBuffer);
-            }
-            vaos.dispose();
+        if (glVertexBuffer) {
+            rs.vertexBufferUnset(glVertexBuffer);
+            GL::deleteBuffers(1, &glVertexBuffer);
+        }
+        if (glIndexBuffer) {
+            rs.indexBufferUnset(glIndexBuffer);
+            GL::deleteBuffers(1, &glIndexBuffer);
         }
+        vaos.dispose();
     });
 
 
@@ -156,7 +151,6 @@ void MeshBase::upload(RenderState& rs) {
         m_glIndexData = nullptr;
     }
 
-    m_generation = rs.generation();
     m_disposer = Disposer(rs);
 
     m_isUploaded = true;
@@ -165,8 +159,6 @@ void MeshBase::upload(RenderState& rs) {
 bool MeshBase::draw(RenderState& rs, ShaderProgram& _shader, bool _useVao) {
     bool useVao = _useVao && Hardware::supportsVAOs;
 
-    checkValidity(rs);
-
     if (!m_isCompiled) { return false; }
     if (m_nVertices == 0) { return false; }
 
@@ -232,21 +224,6 @@ bool MeshBase::draw(RenderState& rs, ShaderProgram& _shader, bool _useVao) {
     return true;
 }
 
-bool MeshBase::checkValidity(RenderState& rs) {
-    if (!rs.isValidGeneration(m_generation)) {
-        m_isUploaded = false;
-        m_glVertexBuffer = 0;
-        m_glIndexBuffer = 0;
-        m_vaos = {};
-
-        m_generation = rs.generation();
-
-        return false;
-    }
-
-    return true;
-}
-
 size_t MeshBase::bufferSize() const {
     return m_nVertices * m_vertexLayout->getStride() + m_nIndices * sizeof(GLushort);
 }

core/src/gl/mesh.h

@@ -76,8 +76,6 @@ struct MeshBase {
 
 protected:
 
-    int m_generation; // Generation in which this mesh's GL handles were created
-
     // Used in draw for legth and offsets: sumIndices, sumVertices
     // needs to be set by compile()
     std::vector<std::pair<uint32_t, uint32_t>> m_vertexOffsets;
@@ -109,8 +107,6 @@ struct MeshBase {
 
     Disposer m_disposer;
 
-    bool checkValidity(RenderState& rs);
-
     size_t compileIndices(const std::vector<std::pair<uint32_t, uint32_t>>& _offsets,
                           const std::vector<uint16_t>& _indices, size_t _offset);
 

core/src/gl/renderState.cpp

@@ -95,19 +95,6 @@ void RenderState::cacheDefaultFramebuffer() {
     GL::getIntegerv(GL_FRAMEBUFFER_BINDING, &m_defaultFramebuffer);
 }
 
-void RenderState::increaseGeneration() {
-    generateQuadIndexBuffer();
-    m_validGeneration++;
-}
-
-bool RenderState::isValidGeneration(int _generation) {
-    return _generation == m_validGeneration;
-}
-
-int RenderState::generation() {
-    return m_validGeneration;
-}
-
 int RenderState::nextAvailableTextureUnit() {
     if (m_nextTextureUnit >= Hardware::maxCombinedTextureUnits) {
         LOGE("Too many combined texture units are being used");

core/src/gl/renderState.h

@@ -31,12 +31,6 @@ class RenderState {
     // Reset the render states.
     void invalidate();
 
-    int generation();
-
-    void increaseGeneration();
-
-    bool isValidGeneration(int _generation);
-
     // Get the texture slot from a texture unit from 0 to TANGRAM_MAX_TEXTURE_UNIT-1.
     static GLuint getTextureUnit(GLuint _unit);
 
@@ -119,7 +113,6 @@ class RenderState {
 
 private:
 
-    int m_validGeneration = 0;
     uint32_t m_nextTextureUnit = 0;
 
     GLuint m_quadIndexBuffer = 0;

core/src/gl/shaderProgram.cpp

@@ -20,14 +20,11 @@ ShaderProgram::ShaderProgram() {
 
 ShaderProgram::~ShaderProgram() {
 
-    auto generation = m_generation;
     auto glProgram = m_glProgram;
 
     m_disposer([=](RenderState& rs) {
-        if (rs.isValidGeneration(generation)) {
-            if (glProgram != 0) {
-                GL::deleteProgram(glProgram);
-            }
+        if (glProgram != 0) {
+            GL::deleteProgram(glProgram);
         }
         // Deleting the shader program that is currently in-use sets the current shader program to 0
         // so we un-set the current program in the render state.
@@ -89,39 +86,29 @@ GLint ShaderProgram::getAttribLocation(const std::string& _attribName) {
 
 GLint ShaderProgram::getUniformLocation(const UniformLocation& _uniform) {
 
-    if (m_generation == _uniform.generation) {
-        return _uniform.location;
-    }
-
-    _uniform.generation = m_generation;
     _uniform.location = GL::getUniformLocation(m_glProgram, _uniform.name.c_str());
 
     return _uniform.location;
 }
 
 bool ShaderProgram::use(RenderState& rs) {
-    bool valid = true;
-
-    checkValidity(rs);
 
     if (m_needsBuild) {
         build(rs);
     }
 
-    valid &= (m_glProgram != 0);
-
-    if (valid) {
+    if (isValid()) {
         rs.shaderProgram(m_glProgram);
+        return true;
     }
 
-    return valid;
+    return false;
 }
 
 bool ShaderProgram::build(RenderState& rs) {
 
     if (!m_needsBuild) { return false; }
     m_needsBuild = false;
-    m_generation = rs.generation();
 
     // Delete handle for old program; values of 0 are silently ignored
     GL::deleteProgram(m_glProgram);
@@ -316,15 +303,6 @@ std::string ShaderProgram::applySourceBlocks(const std::string& source, bool fra
     return sourceOut.str();
 }
 
-void ShaderProgram::checkValidity(RenderState& rs) {
-
-    if (!rs.isValidGeneration(m_generation)) {
-        m_glProgram = 0;
-        m_needsBuild = true;
-        m_uniformCache.clear();
-    }
-}
-
 std::string ShaderProgram::getExtensionDeclaration(const std::string& _extension) {
     std::ostringstream oss;
     oss << "#if defined(GL_ES) == 0 || defined(GL_" << _extension << ")\n";

core/src/gl/shaderProgram.h

@@ -53,7 +53,7 @@ class ShaderProgram {
     GLint getUniformLocation(const UniformLocation& _uniformName);
 
     // Return true if this object represents a valid OpenGL shader program.
-    bool isValid(RenderState& rs) const { return m_glProgram != 0; };
+    bool isValid() const { return m_glProgram != 0; };
 
     // Bind the program in OpenGL if it is not already bound; If the shader sources
     // have been modified since the last time build() was called, also calls build().
@@ -123,7 +123,6 @@ class ShaderProgram {
         return false;
     }
 
-    int m_generation = -1;
     GLuint m_glProgram = 0;
 
     fastmap<std::string, GLint> m_attribMap;
@@ -141,8 +140,6 @@ class ShaderProgram {
 
     Disposer m_disposer;
 
-    void checkValidity(RenderState& rs);
-
     std::string applySourceBlocks(const std::string& source, bool fragShader) const;
 
 };