[core] Eliminate constant attribute bindings

Rather than binding constant attributes that will never be used, just disable the attribute.

1 files changed, 21 insertions, 155 deletions

diff --git a/src/mbgl/gl/attribute.cpp b/src/mbgl/gl/attribute.cpp
index 8c52121f6e..e05ca75866 100644
--- a/src/mbgl/gl/attribute.cpp
+++ b/src/mbgl/gl/attribute.cpp
@@ -10,6 +10,10 @@ AttributeLocation bindAttributeLocation(ProgramID id, AttributeLocation location
     return location;
 }
 
+void DisabledAttribute::bind(Context&, AttributeLocation location, std::size_t) const {
+    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
+}
+
 template <class T> DataType DataTypeOf    = static_cast<DataType>(0);
 template <> DataType DataTypeOf< int8_t>  = DataType::Byte;
 template <> DataType DataTypeOf<uint8_t>  = DataType::UnsignedByte;
@@ -20,16 +24,9 @@ template <> DataType DataTypeOf<uint32_t> = DataType::UnsignedInteger;
 template <> DataType DataTypeOf<float>    = DataType::Float;
 
 template <class T, std::size_t N>
-void VariableAttributeBinding<T, N>::bind(Context& context,
-                                          AttributeLocation location,
-                                          optional<VariableAttributeBinding<T, N>>& oldBinding,
-                                          std::size_t vertexOffset) const {
-    if (oldBinding == *this) {
-        return;
-    }
+void AttributeBinding<T, N>::bind(Context& context, AttributeLocation location, std::size_t vertexOffset) const {
     context.vertexBuffer = vertexBuffer;
     MBGL_CHECK_ERROR(glEnableVertexAttribArray(location));
-    oldBinding = *this;
     MBGL_CHECK_ERROR(glVertexAttribPointer(
         location,
         static_cast<GLint>(attributeSize),
@@ -39,156 +36,25 @@ void VariableAttributeBinding<T, N>::bind(Context& context,
         reinterpret_cast<GLvoid*>(attributeOffset + (vertexSize * vertexOffset))));
 }
 
-template class VariableAttributeBinding<uint8_t, 1>;
-template class VariableAttributeBinding<uint8_t, 2>;
-template class VariableAttributeBinding<uint8_t, 3>;
-template class VariableAttributeBinding<uint8_t, 4>;
-
-template class VariableAttributeBinding<uint16_t, 1>;
-template class VariableAttributeBinding<uint16_t, 2>;
-template class VariableAttributeBinding<uint16_t, 3>;
-template class VariableAttributeBinding<uint16_t, 4>;
-
-template class VariableAttributeBinding<int16_t, 1>;
-template class VariableAttributeBinding<int16_t, 2>;
-template class VariableAttributeBinding<int16_t, 3>;
-template class VariableAttributeBinding<int16_t, 4>;
-
-template class VariableAttributeBinding<float, 1>;
-template class VariableAttributeBinding<float, 2>;
-template class VariableAttributeBinding<float, 3>;
-template class VariableAttributeBinding<float, 4>;
-
-template <>
-void ConstantAttributeBinding<uint8_t, 1>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<uint8_t, 1>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib1f(location, value[0]));
-}
-
-template <>
-void ConstantAttributeBinding<uint8_t, 2>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<uint8_t, 2>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib2f(location, value[0], value[1]));
-}
-
-template <>
-void ConstantAttributeBinding<uint8_t, 3>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<uint8_t, 3>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib3f(location, value[0], value[1], value[2]));
-}
-
-template <>
-void ConstantAttributeBinding<uint8_t, 4>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<uint8_t, 4>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib4f(location, value[0], value[1], value[2], value[3]));
-}
-
-
-template <>
-void ConstantAttributeBinding<uint16_t, 1>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<uint16_t, 1>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib1f(location, value[0]));
-}
-
-template <>
-void ConstantAttributeBinding<uint16_t, 2>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<uint16_t, 2>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib2f(location, value[0], value[1]));
-}
-
-template <>
-void ConstantAttributeBinding<uint16_t, 3>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<uint16_t, 3>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib3f(location, value[0], value[1], value[2]));
-}
-
-template <>
-void ConstantAttributeBinding<uint16_t, 4>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<uint16_t, 4>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib4f(location, value[0], value[1], value[2], value[3]));
-}
-
-
-template <>
-void ConstantAttributeBinding<int16_t, 1>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<int16_t, 1>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib1f(location, value[0]));
-}
+template class AttributeBinding<uint8_t, 1>;
+template class AttributeBinding<uint8_t, 2>;
+template class AttributeBinding<uint8_t, 3>;
+template class AttributeBinding<uint8_t, 4>;
 
-template <>
-void ConstantAttributeBinding<int16_t, 2>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<int16_t, 2>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib2f(location, value[0], value[1]));
-}
+template class AttributeBinding<uint16_t, 1>;
+template class AttributeBinding<uint16_t, 2>;
+template class AttributeBinding<uint16_t, 3>;
+template class AttributeBinding<uint16_t, 4>;
 
-template <>
-void ConstantAttributeBinding<int16_t, 3>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<int16_t, 3>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib3f(location, value[0], value[1], value[2]));
-}
+template class AttributeBinding<int16_t, 1>;
+template class AttributeBinding<int16_t, 2>;
+template class AttributeBinding<int16_t, 3>;
+template class AttributeBinding<int16_t, 4>;
 
-template <>
-void ConstantAttributeBinding<int16_t, 4>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<int16_t, 4>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib4f(location, value[0], value[1], value[2], value[3]));
-}
-
-
-template <>
-void ConstantAttributeBinding<float, 1>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<float, 1>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib1f(location, value[0]));
-}
-
-template <>
-void ConstantAttributeBinding<float, 2>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<float, 2>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib2f(location, value[0], value[1]));
-}
-
-template <>
-void ConstantAttributeBinding<float, 3>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<float, 3>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib3f(location, value[0], value[1], value[2]));
-}
-
-template <>
-void ConstantAttributeBinding<float, 4>::bind(Context&, AttributeLocation location, optional<VariableAttributeBinding<float, 4>>& oldBinding, std::size_t) const {
-    assert(location != 0);
-    oldBinding = {};
-    MBGL_CHECK_ERROR(glDisableVertexAttribArray(location));
-    MBGL_CHECK_ERROR(glVertexAttrib4f(location, value[0], value[1], value[2], value[3]));
-}
+template class AttributeBinding<float, 1>;
+template class AttributeBinding<float, 2>;
+template class AttributeBinding<float, 3>;
+template class AttributeBinding<float, 4>;
 
 } // namespace gl
 } // namespace mbgl