JNI layer and some java implementation for passing route altitude chart image from cpp to java.

android/jni/com/mapswithme/maps/Framework.cpp

@@ -5,6 +5,7 @@
 #include "com/mapswithme/opengl/androidoglcontextfactory.hpp"
 #include "com/mapswithme/platform/Platform.hpp"
 
+#include "map/chart_generator.hpp"
 #include "map/user_mark.hpp"
 
 #include "search/everywhere_search_params.hpp"
@@ -891,6 +892,51 @@ Java_com_mapswithme_maps_Framework_nativeGetRouteFollowingInfo(JNIEnv * env, jcl
   return result;
 }
 
+JNIEXPORT jintArray JNICALL
+Java_com_mapswithme_maps_Framework_nativeGenerateRouteAltitudeChartBits(JNIEnv * env, jclass, jint width, jint height)
+{
+  ::Framework * fr = frm();
+  ASSERT(fr, ());
+  vector<uint8_t> imageRGBAData;
+
+  if (!fr->GenerateRouteAltitudeChart(width, height, imageRGBAData))
+  {
+    LOG(LWARNING, ("Cann't generate route altitude image."));
+    return nullptr;
+  }
+
+  size_t const imageRGBADataSize = imageRGBAData.size();
+  if (imageRGBADataSize == 0)
+  {
+    LOG(LWARNING, ("GenerateRouteAltitudeChart returns true but the vector with altitude image bits is empty."));
+    return nullptr;
+  }
+
+  size_t const pxlCount = width * height;
+  if (maps::kAlitudeChartBPP * pxlCount != imageRGBAData.size())
+  {
+    LOG(LWARNING, ("Wrong size of vector with altitude image bits. Expected size:", pxlCount, ". Real size:", imageRGBAData.size()));
+    return nullptr;
+  }
+
+  jintArray imageRGBADataArray = env->NewIntArray(imageRGBADataSize);
+  ASSERT(imageRGBADataArray, ());
+  jint * arrayElements = env->GetIntArrayElements(imageRGBADataArray, 0);
+  ASSERT(arrayElements, ());
+
+  for (size_t i = 0; i < imageRGBADataSize; ++i)
+  {
+    size_t const shiftInBytes = i * maps::kAlitudeChartBPP;
+    arrayElements[i] = (imageRGBAData[shiftInBytes + 3] << 24) /* alpha */
+        | (imageRGBAData[shiftInBytes] << 16) /* red */
+        | (imageRGBAData[shiftInBytes + 1] << 8) /* green */
+        | (imageRGBAData[shiftInBytes + 2]); /* blue */
+  }
+  env->ReleaseIntArrayElements(imageRGBADataArray, arrayElements, 0);
+
+  return imageRGBADataArray;
+}
+
 JNIEXPORT void JNICALL
 Java_com_mapswithme_maps_Framework_nativeShowCountry(JNIEnv * env, jclass, jstring countryId, jboolean zoomToDownloadButton)
 {

android/src/com/mapswithme/maps/Framework.java

@@ -1,5 +1,6 @@
 package com.mapswithme.maps;
 
+import android.graphics.Bitmap;
 import android.support.annotation.IntDef;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
@@ -68,6 +69,25 @@ public class Framework
     return nativeGetGe0Url(lat, lon, zoomLevel, name).replaceFirst(Constants.Url.GE0_PREFIX, Constants.Url.HTTP_GE0_PREFIX);
   }
 
+  /**
+   * Generates Bitmap with route altitude image chart taking into account current map style.
+   * @param width is width of the image.
+   * @param height is height of the image.
+   * @return Bitmap if there's pedestrian of bicycle route and null otherwise.
+   */
+  @Nullable
+  public static Bitmap GenerateRouteAltitudeChart(int width, int height)
+  {
+    if (width <= 0 || height <= 0)
+      return null;
+
+    final int[] altitudeChartBits = Framework.nativeGenerateRouteAltitudeChartBits(width, height);
+    if (altitudeChartBits == null)
+      return null;
+
+    return Bitmap.createBitmap(altitudeChartBits, width, height, Bitmap.Config.ARGB_8888);
+  }
+
   public static native void nativeShowTrackRect(int category, int track);
 
   public static native int nativeGetDrawScale();
@@ -144,6 +164,9 @@ public class Framework
   @Nullable
   public static native RoutingInfo nativeGetRouteFollowingInfo();
 
+  @Nullable
+  public static native final int [] nativeGenerateRouteAltitudeChartBits(int width, int height);
+
   // When an end user is going to a turn he gets sound turn instructions.
   // If C++ part wants the client to pronounce an instruction nativeGenerateTurnNotifications returns
   // an array of one of more strings. C++ part assumes that all these strings shall be pronounced by the client's TTS.