Refactor tileCover to support lod tiles

2 files changed, 11 insertions, 1 deletions

diff --git a/src/mbgl/map/transform_state.cpp b/src/mbgl/map/transform_state.cpp
index b5513f3d83..1894c59e2b 100644
--- a/src/mbgl/map/transform_state.cpp
+++ b/src/mbgl/map/transform_state.cpp
@@ -171,9 +171,12 @@ void TransformState::updateMatricesIfNeeded() const {
     getProjMatrix(projectionMatrix);
     coordMatrix = coordinatePointMatrix(projectionMatrix);
 
-    bool err = matrix::invert(invertedMatrix, coordMatrix);
+    bool err = matrix::invert(invProjectionMatrix, projectionMatrix);
+    if (err) throw std::runtime_error("failed to invert projectionMatrix");
 
+    err = matrix::invert(invertedMatrix, coordMatrix);
     if (err) throw std::runtime_error("failed to invert coordinatePointMatrix");
+
     requestMatricesUpdate = false;
 }
 
@@ -182,6 +185,11 @@ const mat4& TransformState::getProjectionMatrix() const {
     return projectionMatrix;
 }
 
+const mat4& TransformState::getInvProjectionMatrix() const {
+    updateMatricesIfNeeded();
+    return invProjectionMatrix;
+}
+
 const mat4& TransformState::getCoordMatrix() const {
     updateMatricesIfNeeded();
     return coordMatrix;
diff --git a/src/mbgl/map/transform_state.hpp b/src/mbgl/map/transform_state.hpp
index b7fa97eea6..69f0eebd40 100644
--- a/src/mbgl/map/transform_state.hpp
+++ b/src/mbgl/map/transform_state.hpp
@@ -216,6 +216,7 @@ public:
 
     void constrain(double& scale, double& x, double& y) const;
     const mat4& getProjectionMatrix() const;
+    const mat4& getInvProjectionMatrix() const;
 
 private:
     bool rotatedNorth() const;
@@ -282,6 +283,7 @@ private:
 
     mutable bool requestMatricesUpdate{true};
     mutable mat4 projectionMatrix;
+    mutable mat4 invProjectionMatrix;
     mutable mat4 coordMatrix;
     mutable mat4 invertedMatrix;
 };