[core] add maxzoom uniform for raster-dem tilesets (#11134)

* add maxzoom uniform to support external tilesets

* update git sha for gl-js

* try and fix android crash

* name default maxzoom constant

4 files changed, 14 insertions, 3 deletions

diff --git a/src/mbgl/renderer/layers/render_hillshade_layer.cpp b/src/mbgl/renderer/layers/render_hillshade_layer.cpp
index 55702849df..bcfd4ffe99 100644
--- a/src/mbgl/renderer/layers/render_hillshade_layer.cpp
+++ b/src/mbgl/renderer/layers/render_hillshade_layer.cpp
@@ -1,6 +1,7 @@
 #include <mbgl/renderer/layers/render_hillshade_layer.hpp>
 #include <mbgl/renderer/buckets/hillshade_bucket.hpp>
 #include <mbgl/renderer/render_tile.hpp>
+#include <mbgl/renderer/sources/render_raster_dem_source.hpp>
 #include <mbgl/renderer/paint_parameters.hpp>
 #include <mbgl/renderer/render_static_data.hpp>
 #include <mbgl/programs/programs.hpp>
@@ -55,10 +56,14 @@ bool RenderHillshadeLayer::hasTransition() const {
     return unevaluated.hasTransition();
 }
 
-void RenderHillshadeLayer::render(PaintParameters& parameters, RenderSource*) {
+void RenderHillshadeLayer::render(PaintParameters& parameters, RenderSource* src) {
     if (parameters.pass != RenderPass::Translucent && parameters.pass != RenderPass::Pass3D)
         return;
     
+    RenderRasterDEMSource* demsrc = dynamic_cast<RenderRasterDEMSource*>(src);
+    const uint8_t TERRAIN_RGB_MAXZOOM = 15;
+    const uint8_t maxzoom = demsrc != nullptr ? demsrc->getMaxZoom() : TERRAIN_RGB_MAXZOOM;
+
     auto draw = [&] (const mat4& matrix,
                      const auto& vertexBuffer,
                      const auto& indexBuffer,
@@ -118,6 +123,7 @@ void RenderHillshadeLayer::render(PaintParameters& parameters, RenderSource*) {
                     uniforms::u_matrix::Value { mat },
                     uniforms::u_dimension::Value { {{uint16_t(tilesize * 2), uint16_t(tilesize * 2) }} },
                     uniforms::u_zoom::Value{ float(tile.id.canonical.z) },
+                    uniforms::u_maxzoom::Value{ float(maxzoom) },
                     uniforms::u_image::Value{ 0 }
                 },
                 parameters.staticData.rasterVertexBuffer,
diff --git a/src/mbgl/renderer/layers/render_hillshade_layer.hpp b/src/mbgl/renderer/layers/render_hillshade_layer.hpp
index e9b9db1ec3..13093ee7ef 100644
--- a/src/mbgl/renderer/layers/render_hillshade_layer.hpp
+++ b/src/mbgl/renderer/layers/render_hillshade_layer.hpp
@@ -16,7 +16,7 @@ public:
     void evaluate(const PropertyEvaluationParameters&) override;
     bool hasTransition() const override;
 
-    void render(PaintParameters&, RenderSource*) override;
+    void render(PaintParameters&, RenderSource* src) override;
 
     std::unique_ptr<Bucket> createBucket(const BucketParameters&, const std::vector<const RenderLayer*>&) const override;
 
diff --git a/src/mbgl/renderer/sources/render_raster_dem_source.cpp b/src/mbgl/renderer/sources/render_raster_dem_source.cpp
index fb8f2c69d4..b3153622c3 100644
--- a/src/mbgl/renderer/sources/render_raster_dem_source.cpp
+++ b/src/mbgl/renderer/sources/render_raster_dem_source.cpp
@@ -36,7 +36,7 @@ void RenderRasterDEMSource::update(Immutable<style::Source::Impl> baseImpl_,
 
     if (tileset != _tileset) {
         tileset = _tileset;
-
+        maxzoom = tileset->zoomRange.max;
         // TODO: this removes existing buckets, and will cause flickering.
         // Should instead refresh tile data in place.
         tilePyramid.tiles.clear();
diff --git a/src/mbgl/renderer/sources/render_raster_dem_source.hpp b/src/mbgl/renderer/sources/render_raster_dem_source.hpp
index 3c2a90c37f..741214a14d 100644
--- a/src/mbgl/renderer/sources/render_raster_dem_source.hpp
+++ b/src/mbgl/renderer/sources/render_raster_dem_source.hpp
@@ -36,11 +36,16 @@ public:
     void reduceMemoryUse() final;
     void dumpDebugLogs() const final;
 
+    uint8_t getMaxZoom() const {
+        return maxzoom;
+    };
+
 private:
     const style::RasterSource::Impl& impl() const;
 
     TilePyramid tilePyramid;
     optional<Tileset> tileset;
+    uint8_t maxzoom = 15;
 
 protected:
     void onTileChanged(Tile&) final;