android - OpenGL ES 2.0 diffuse lighting: model shows up black -

this problem bothers me week... tried load stl files , show on screen. file read properly. rendering without adding light pretty good. after add lighting , shader codes, model still there turns out black.

i followed example downloaded link below article: http://www.learnopengles.com/android-lesson-two-ambient-and-diffuse-lighting/

the shader code same example. program links fine. shaders compile fine, too. can't find out problem is. plz me.

my renderer:

public class myglrenderer implements glsurfaceview.renderer {   private test test;  private light1 light1;   private float range = 145;   private final float[] mmvmmatrix = new float[16];  private final float[] mmvpmatrix = new float[16];  private final float[] mmodelmatrix = new float[16];  private final float[] mprojectionmatrix = new float[16];  private final float[] mviewmatrix = new float[16];  protected final static float[] mlightposineyespace = new float[4];  private final float[] mlightmodelmatrix = new float[16];  private final float[] mlightposinmodelspace = new float[] {0.0f, 0.0f, 0.0f, 1.0f};  private final float[] mlightposinworldspace = new float[4];   private final float[] mtempmatrix = new float[16];  public static final float[] maccumulatedmatrix = new float[16];  private final float[] mcurrmatrix = new float[16];    public void onsurfacecreated(gl10 unused, eglconfig config) {     // set background frame color     gles20.glclearcolor(0.0f, 0.0f, 0.0f, 0.0f);     gles20.glenable(gles20.gl_depth_test);     gles20.gldepthfunc(gles20.gl_lequal);     matrix.setidentitym(mtempmatrix, 0);     matrix.setidentitym(maccumulatedmatrix, 0);      light1 = new light1();     test = new test();   }   public void ondrawframe(gl10 unused) {     gles20.glclear(gles20.gl_color_buffer_bit | gles20.gl_depth_buffer_bit);      matrix.setidentitym(mviewmatrix, 0);     matrix.setidentitym(mmodelmatrix, 0);     matrix.setidentitym(mcurrmatrix, 0);     matrix.setidentitym(mlightmodelmatrix, 0);      matrix.multiplymv(mlightposinworldspace, 0, mlightmodelmatrix, 0, mlightposinmodelspace, 0);     matrix.multiplymv(mlightposineyespace, 0, mviewmatrix, 0, mlightposinworldspace, 0);      matrix.rotatem(mcurrmatrix, 0, mangley, 0.0f, 1.0f, 0.0f);     matrix.rotatem(mcurrmatrix, 0, manglex, 1.0f, 0, 0.0f);     manglex = 0.0f;     mangley = 0.0f;      matrix.multiplymm(mtempmatrix, 0, mcurrmatrix, 0, maccumulatedmatrix, 0);     system.arraycopy(mtempmatrix, 0, maccumulatedmatrix, 0, 16);      matrix.multiplymm(mtempmatrix, 0, mmodelmatrix, 0, maccumulatedmatrix, 0);     system.arraycopy(mtempmatrix, 0, mmodelmatrix, 0, 16);      matrix.translatem(mmodelmatrix, 0, -test.meanx, -test.meany, -test.meanz);      matrix.multiplymm(mmvmmatrix, 0, mviewmatrix, 0, mmodelmatrix, 0);     matrix.multiplymm(mmvpmatrix, 0, mprojectionmatrix, 0, mmvmmatrix, 0);      light1.draw(mmvpmatrix);      test.draw(mmvpmatrix, mmvmmatrix);  }   public void onsurfacechanged(gl10 gl, int width, int height) {     gles20.glviewport(0, 0, width, height);      float ratio = (float) width / height;     matrix.orthom(mprojectionmatrix, 0, -range*ratio, range*ratio, -range, range, -range, range);  }   public final static int loadshader(int type, string shadercode){     int shader = gles20.glcreateshader(type);     gles20.glshadersource(shader, shadercode);     gles20.glcompileshader(shader);     return shader;  }   public static volatile float manglex;  public static volatile float mangley;   public static void setanglex(float angle) {manglex = angle;}   public float getanglex() {      return manglex;  }   public static void setangley(float angle) {     mangley = angle;  }   public float getangley() {     return mangley;  }} 

my code draw light is:

public class light1 { private final string vertexshadercode =         "uniform mat4 u_mvpmatrix;      \n"                 +   "attribute vec4 a_position;     \n"                 + "void main()                    \n"                 + "{                              \n"                 + "   gl_position = u_mvpmatrix   \n"                 + "               * a_position;   \n"                 + "   gl_pointsize = 5.0;         \n"                 + "}                              \n";  private final string fragmentshadercode =         "precision mediump float;       \n"                 + "void main()                    \n"                 + "{                              \n"                 + "   gl_fragcolor = vec4(1.0,    \n"                 + "   1.0, 1.0, 1.0);             \n"                 + "}                              \n";    //light******************* public static float[] lightlocation = new float[] {150, 150, 0};//*********ok private final int mprogram; //light*******************   public light1() {     // initialize byte buffer draw list     int vertexshader = myglrenderer.loadshader(             gles20.gl_vertex_shader,             vertexshadercode);     int fragmentshader = myglrenderer.loadshader(             gles20.gl_fragment_shader,             fragmentshadercode);      mprogram = gles20.glcreateprogram();     gles20.glattachshader(mprogram, vertexshader);     gles20.glattachshader(mprogram, fragmentshader);     gles20.gllinkprogram(mprogram); }  public void draw(float[] mvpmatrix) {      gles20.gluseprogram(mprogram);     final int pointmvpmatrixhandle = gles20.glgetuniformlocation(mprogram, "u_mvpmatrix");     final int pointpositionhandle = gles20.glgetattriblocation(mprogram, "a_position");      gles20.glvertexattrib3f(pointpositionhandle, lightlocation[0], lightlocation[1], lightlocation[2]);      gles20.gluniformmatrix4fv(pointmvpmatrixhandle, 1, false, mvpmatrix, 0);      gles20.gldrawarrays(gles20.gl_points, 0, 1);      gles20.gldisablevertexattribarray(pointpositionhandle); }} 

my model code:

public class test { final string vertexshadercode =         "uniform mat4 u_mvpmatrix;      \n"     // constant representing combined model/view/projection matrix.                 + "uniform mat4 u_mvmatrix;       \n"       // constant representing combined model/view matrix.                 + "uniform vec3 u_lightpos;       \n"       // position of light in eye space.                  + "attribute vec4 a_position;     \n"       // per-vertex position information pass in.                 + "attribute vec4 a_color;        \n"       // per-vertex color information pass in.                 + "attribute vec3 a_normal;       \n"       // per-vertex normal information pass in.                  + "varying vec4 v_color;          \n"       // passed fragment shader.                  + "void main()                    \n"   // entry point our vertex shader.                 + "{                              \n"                 // transform vertex eye space.                 + "   vec3 modelviewvertex = vec3(u_mvmatrix * a_position);              \n"                 // transform normal's orientation eye space.                 + "   vec3 modelviewnormal = vec3(u_mvmatrix * vec4(a_normal, 0.0));     \n"                 // used attenuation.                 + "   float distance = length(u_lightpos - modelviewvertex);             \n"                 // lighting direction vector light vertex.                 + "   vec3 lightvector = normalize(u_lightpos - modelviewvertex);        \n"                 // calculate dot product of light vector , vertex normal. if normal , light vector                 // pointing in same direction max illumination.                 + "   float diffuse = max(dot(modelviewnormal, lightvector), 0.1);       \n"                 // attenuate light based on distance.                 + "   diffuse = diffuse * (1.0 / (1.0 + (0.25 * distance * distance)));  \n"                 // multiply color illumination level. interpolated across triangle.                 + "   v_color = a_color * diffuse;                                       \n"                 // gl_position special variable used store final position.                 // multiply vertex matrix final point in normalized screen coordinates.                 + "   gl_position = u_mvpmatrix * a_position;                            \n"                 + "}                                                                     \n";  private final string fragmentshadercode =         "precision mediump float;       \n"     // set default precision medium. don't need high of                 // precision in fragment shader.                 + "varying vec4 v_color;          \n"       // color vertex shader interpolated across                 // triangle per fragment.                 + "void main()                    \n"       // entry point our fragment shader.                 + "{                              \n"                 + "   gl_fragcolor = v_color;     \n"       // pass color directly through pipeline.                 + "}                              \n";  private floatbuffer vertexbuffer; private floatbuffer colorbuffer; private floatbuffer normalbuffer;  private final int mprogram;  private int mpositionhandle; private int mnormalhandle; private int mlightlocationhandle; private int mcolorhandle; private int mmvpmatrixhandle; private int mmvmatrixhandle;  final int coords_per_vertex = 3; float[] squarecoords; float[] coordsnormals;  float color[];  public test() {     squarecoords = glassui10.readstlbinary("test.stl");     coordsnormals = vectorcalculate.getnormbyptarray(squarecoords);     color = new float[squarecoords.length/3*4];     for(int = 0; < color.length/4 ; = i+4)     {         color[i+0] =0.3f;         color[i+1] =0.7f;         color[i+2] =0.6f;         color[i+3] =1.3f;     }     system.gc();     log.v("testloaded: ", "loaded");      // initialize vertex byte buffer shape coordinates     bytebuffer bb = bytebuffer.allocatedirect(squarecoords.length * 4);     bb.order(byteorder.nativeorder());     vertexbuffer = bb.asfloatbuffer();     vertexbuffer.put(squarecoords);     vertexbuffer.position(0);      colorbuffer = bytebuffer.allocatedirect(color.length * 4)             .order(byteorder.nativeorder()).asfloatbuffer();     colorbuffer.put(color).position(0);      bytebuffer nb = bytebuffer.allocatedirect(coordsnormals.length * 4);     nb.order(byteorder.nativeorder());     normalbuffer = nb.asfloatbuffer();     normalbuffer.put(coordsnormals);     normalbuffer.position(0);      // initialize byte buffer draw list     int vertexshader = myglrenderer.loadshader(             gles20.gl_vertex_shader,             vertexshadercode);//*********ok     int fragmentshader = myglrenderer.loadshader(             gles20.gl_fragment_shader,             fragmentshadercode);//*********ok      mprogram = gles20.glcreateprogram();     gles20.glattachshader(mprogram, vertexshader);     gles20.glattachshader(mprogram, fragmentshader);     gles20.glbindattriblocation(mprogram, 0, "a_position");     gles20.glbindattriblocation(mprogram, 1, "a_color");     gles20.glbindattriblocation(mprogram, 2, "a_normal");        gles20.gllinkprogram(mprogram); }  public void draw(float[] mvpmatrix, float[] mvmatrix) {      gles20.gluseprogram(mprogram);      mmvpmatrixhandle = gles20.glgetuniformlocation(mprogram, "u_mvpmatrix");     mmvmatrixhandle = gles20.glgetuniformlocation(mprogram, "u_mvmatrix");     mlightlocationhandle = gles20.glgetuniformlocation(mprogram, "u_lightpos");     mpositionhandle = gles20.glgetattriblocation(mprogram, "a_position");     mcolorhandle = gles20.glgetuniformlocation(mprogram, "a_color");     mnormalhandle = gles20.glgetattriblocation(mprogram, "a_normal");      vertexbuffer.position(0);     gles20.glvertexattribpointer(mpositionhandle, coords_per_vertex, gles20.gl_float, false, 0, vertexbuffer);     gles20.glenablevertexattribarray(mpositionhandle);      colorbuffer.position(0);     gles20.glvertexattribpointer(mcolorhandle, 4, gles20.gl_float, false, 0, colorbuffer);     gles20.glenablevertexattribarray(mcolorhandle);      normalbuffer.position(0);     gles20.glvertexattribpointer(mnormalhandle, coords_per_vertex, gles20.gl_float, false, 0, normalbuffer);     gles20.glenablevertexattribarray(mnormalhandle);      gles20.gluniformmatrix4fv(mmvmatrixhandle, 1, false, mvmatrix, 0);      gles20.gluniformmatrix4fv(mmvpmatrixhandle, 1, false, mvpmatrix, 0);      gles20.gluniform3f(mlightlocationhandle, myglrenderer.mlightposineyespace[0],  myglrenderer.mlightposineyespace[1],  myglrenderer.mlightposineyespace[2]);      gles20.gldrawarrays(gles20.gl_triangles, 0, squarecoords.length/coords_per_vertex);              gles20.gldrawarrays(gles20.gl_triangles, 0, vertexcount);      gles20.gldisablevertexattribarray(mpositionhandle); }} 

any answer appreciated!

in code, coords_per_vertex 3. in shader code "attribute vec4 a_position; \n", a_position vec4.

so gles20.glvertexattribpointer(mpositionhandle, coords_per_vertex, gles20.gl_float, false, 0, vertexbuffer); has incompatible vector size.