[core] Limit pitch based on edge insets. Fix max Z calculation in getProjMatrix.

Patch partly fixes #15163 in a way that it doesn't allow loading tens of thousands of tiles and attempt to show area above horizon:

Limit pitch based on edge insets. It is not too bad - current limit of 60 degrees stays active until center of perspective is moved towards the bottom, to 84% of screen height. The plan is to split removal of 60 degrees limit to follow up patch.

Fix max Z calculation in getProjMatrix. TransformState::getProjMatrix calculation of farZ was complex with possibility to lead to negative z values. Replacing it with simpler, precise calculation:
furthestDistance = cameraToCenterDistance / (1 - tanFovAboveCenter * std::tan(getPitch()));

TransformState::getProjMatrix calculation of farZ was an aproximation. Replacing it with simpler, but precise calculation.

Related to: #15163

1 files changed, 3 insertions, 0 deletions

diff --git a/test/map/transform.test.cpp b/test/map/transform.test.cpp
index 3d37312b17..84fdb06b21 100644
--- a/test/map/transform.test.cpp
+++ b/test/map/transform.test.cpp
@@ -9,6 +9,7 @@ using namespace mbgl;
 
 TEST(Transform, InvalidZoom) {
     Transform transform;
+    transform.resize({1, 1});
 
     ASSERT_DOUBLE_EQ(0, transform.getLatLng().latitude());
     ASSERT_DOUBLE_EQ(0, transform.getLatLng().longitude());
@@ -56,6 +57,7 @@ TEST(Transform, InvalidZoom) {
 
 TEST(Transform, InvalidBearing) {
     Transform transform;
+    transform.resize({1, 1});
 
     ASSERT_DOUBLE_EQ(0, transform.getLatLng().latitude());
     ASSERT_DOUBLE_EQ(0, transform.getLatLng().longitude());
@@ -78,6 +80,7 @@ TEST(Transform, InvalidBearing) {
 
 TEST(Transform, IntegerZoom) {
     Transform transform;
+    transform.resize({1, 1});
 
     auto checkIntegerZoom = [&transform](uint8_t zoomInt, double zoom) {
         transform.jumpTo(CameraOptions().withZoom(zoom));