Example usage for android.opengl GLES20 glDrawElements

Introduction

In this page you can find the example usage for android.opengl GLES20 glDrawElements.

Prototype

public static native void glDrawElements(int mode, int count, int type, java.nio.Buffer indices);

Source Link

Usage

From source file:com.sveder.cardboardpassthrough.MainActivity.java

/**
 * Draws a frame for an eye. The transformation for that eye (from the camera) is passed in as
 * a parameter./*from  w w w.  j  a v  a2 s  .c o  m*/
 * @param transform The transformations to apply to render this eye.
 */
@Override
public void onDrawEye(EyeTransform transform) {
    GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);

    GLES20.glUseProgram(mProgram);

    GLES20.glActiveTexture(GL_TEXTURE_EXTERNAL_OES);
    GLES20.glBindTexture(GL_TEXTURE_EXTERNAL_OES, texture);

    mPositionHandle = GLES20.glGetAttribLocation(mProgram, "position");
    GLES20.glEnableVertexAttribArray(mPositionHandle);
    GLES20.glVertexAttribPointer(mPositionHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, vertexStride,
            vertexBuffer);

    mTextureCoordHandle = GLES20.glGetAttribLocation(mProgram, "inputTextureCoordinate");
    GLES20.glEnableVertexAttribArray(mTextureCoordHandle);
    GLES20.glVertexAttribPointer(mTextureCoordHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, vertexStride,
            textureVerticesBuffer);

    mColorHandle = GLES20.glGetAttribLocation(mProgram, "s_texture");

    GLES20.glDrawElements(GLES20.GL_TRIANGLES, drawOrder.length, GLES20.GL_UNSIGNED_SHORT, drawListBuffer);

    // Disable vertex array
    GLES20.glDisableVertexAttribArray(mPositionHandle);
    GLES20.glDisableVertexAttribArray(mTextureCoordHandle);

    Matrix.multiplyMM(mView, 0, transform.getEyeView(), 0, mCamera, 0);

    //        mPositionParam = GLES20.glGetAttribLocation(mGlProgram, "a_Position");
    //        mNormalParam = GLES20.glGetAttribLocation(mGlProgram, "a_Normal");
    //        mColorParam = GLES20.glGetAttribLocation(mGlProgram, "a_Color");
    //
    //        GLES20.glEnableVertexAttribArray(mPositionParam);
    //        GLES20.glEnableVertexAttribArray(mNormalParam);
    //        GLES20.glEnableVertexAttribArray(mColorParam);
    //        checkGLError("mColorParam");
    //
    //        // Apply the eye transformation to the camera.
    //        Matrix.multiplyMM(mView, 0, transform.getEyeView(), 0, mCamera, 0);
    //
    //        // Set the position of the light
    //        Matrix.multiplyMV(mLightPosInEyeSpace, 0, mView, 0, mLightPosInWorldSpace, 0);
    //        GLES20.glUniform3f(mLightPosParam, mLightPosInEyeSpace[0], mLightPosInEyeSpace[1],
    //                mLightPosInEyeSpace[2]);
    //
    //        // Build the ModelView and ModelViewProjection matrices
    //        // for calculating cube position and light.
    //        Matrix.multiplyMM(mModelView, 0, mView, 0, mModelCube, 0);
    //        Matrix.multiplyMM(mModelViewProjection, 0, transform.getPerspective(), 0, mModelView, 0);
    //        drawCube();
    //
    //        // Set mModelView for the floor, so we draw floor in the correct location
    //        Matrix.multiplyMM(mModelView, 0, mView, 0, mModelFloor, 0);
    //        Matrix.multiplyMM(mModelViewProjection, 0, transform.getPerspective(), 0,
    //            mModelView, 0);
    //        drawFloor(transform.getPerspective());
}

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From source file:com.aimfire.gallery.cardboard.PhotoActivity.java

/**
 * Draws a frame for an eye./*from  ww w  . ja  v  a 2s.  c  o m*/
 *
 * @param eye The eye to render. Includes all required transformations.
 */
@Override
public void onDrawEye(Eye eye) {
    if (mAssetInd == -1) {
        // we are still showing instruction, return without doing anything
        return;
    }

    if (!mAssetChangedLeft && !mAssetChangedRight) {
        // nothing changed, do nothing and return
        return;
    }

    if (eye.getType() == Eye.Type.LEFT)
        mAssetChangedLeft = false;
    else if (eye.getType() == Eye.Type.RIGHT)
        mAssetChangedRight = false;

    GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
    checkGLError("mColorParam");

    GLES20.glUseProgram(mPicProgram);

    GLES20.glUniform1f(mDimRatioParam, mDimRatio);

    GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
    if (eye.getType() == Eye.Type.LEFT) {
        GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureCurr[0]);
    } else {
        GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureCurr[1]);
    }

    // set the zoom level
    GLES20.glUniform1f(mZoomParam, sZoom[mImgZoomInd]);

    /*
     * if user prefers negative parallax, shift window on left frame leftward and right frame
     * rightward. if user prefers positive parallax, do the opposite
     */
    if (eye.getType() == Eye.Type.LEFT) {
        GLES20.glUniform1f(mParallaxParam, mImgParallaxAdj / 2.0f);
    } else {
        GLES20.glUniform1f(mParallaxParam, -mImgParallaxAdj / 2.0f);
    }

    // Set the position of the picture
    //float zoomCoords[] = new float[picCoords.length];
    //for(int i=0; i<picCoords.length; i++)
    //zoomCoords[i] = picCoords[i] * zoom[zoomInd];

    //ByteBuffer bblVertices = ByteBuffer.allocateDirect(zoomCoords.length * 4);
    ByteBuffer bblVertices = ByteBuffer.allocateDirect(picCoords.length * 4);
    bblVertices.order(ByteOrder.nativeOrder());
    mPicVertices = bblVertices.asFloatBuffer();
    //mPicVertices.put(zoomCoords);
    mPicVertices.put(picCoords);
    mPicVertices.position(0);

    GLES20.glVertexAttribPointer(mPicPositionParam, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, vertexStride,
            mPicVertices);

    GLES20.glDrawElements(GLES20.GL_TRIANGLES, /* mode */
            6, /* count */
            GLES20.GL_UNSIGNED_SHORT, /* type */
            mPicElements /* element array buffer offset */
    );
}

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