CODEWITHSUNDEEP
androidbitmapandroid-ndk
VKJ
VKJ

Reputation: 417

Create bitmap in ndk level and display

I want to create one bitmap and display it on screen by using ndk code, can anybody tel me how to do that. Sample code is good to understand.

Upvotes: 1

Views: 1197

Answers (1)

sksEng
sksEng

Reputation: 257

Starting from Gingerbread, NativeWindow is your choice to display a bitmap on screen from ndk.

android-ndk-r7b/platforms/android-9/arch-arm/usr/include/android/native_window.h

Looking for the two functions below, int32_t ANativeWindow_lock(ANativeWindow* window, ANativeWindow_Buffer* outBuffer, ARect* inOutDirtyBounds); int32_t ANativeWindow_unlockAndPost(ANativeWindow* window);

It looks very much like java Canvas at android SDK level, right?

To use nativeWnd, you have to pass down a jobject of java SurfaceHolder to ndk, then acquire on the surface to make a nativeWnd.

Then, use ANativeWindow_setBuffersGeometry to setup frame size and color format

Then, ANativeWindow_lock to lock the surface

Then, do your picture bitblt

At last, ANativeWindow_unlockAndPost - your bitmap is on screen

You can also search the Internet to find sample code using native window.

Upvotes: 1

Related Questions