Vuforia:如何用图像目标示例中的文本更改茶壶？

Question

如何在 Vuforia Image Target 示例中更改带有文本内容的茶壶？

该示例位于:https://developer.vuforia.com/resources/sample-apps/image-targets-sample-app

Answer 1

我尝试访问 mbrenon 提供的链接。不幸的是，它们没有加载。

我的解决方案:

您拥有茶壶的原因是因为 Vuforia 使用该类作为要显示的图像。为了拥有平面文本，我创建了自己的 PlaneTextClass。

1. 转到 src->main->java->com.qualcomm.vuforia.samples->SampleApplication->utils。在那里您可以找到可以使用的对象。

2. 添加一个名为“TextPlane”的类并从“MeshObject”扩展

   public class TextPlane extends MeshObject {
   
     private final static double planeVertices[] =
           {
                   -50f, -50f, 0.0f, 50f, -50f, 0.0f, 50f, 50f, 0.0f, -50f, 50f, 0.0f
           };
     private final static double planeTexcoords[] =
           {
                   0, 0, 1, 0, 1, 1, 0, 1
           };
     private final static double planeNormals[] =
           {
                   0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1
           };
     private final static short planeIndices[] =
           {
                   0, 1, 2, 0, 2, 3
           };
   
   
     private Buffer mVertBuff;
     private Buffer mTexCoordBuff;
     private Buffer mNormBuff;
     private Buffer mIndBuff;
   
     public TextPlane(){
       mVertBuff = fillBuffer(planeVertices);
       mTexCoordBuff = fillBuffer(planeTexcoords);
       mNormBuff = fillBuffer(planeNormals);
       mIndBuff = fillBuffer(planeIndices);
     }
   
     @Override
     public Buffer getBuffer(BUFFER_TYPE bufferType) {
       Buffer result = null;
       switch (bufferType)
       {
           case BUFFER_TYPE_VERTEX:
               result = mVertBuff;
               break;
           case BUFFER_TYPE_TEXTURE_COORD:
               result = mTexCoordBuff;
               break;
           case BUFFER_TYPE_INDICES:
               result = mIndBuff;
               break;
           case BUFFER_TYPE_NORMALS:
               result = mNormBuff;
           default:
               break;
        }
       return result;
     }
   
     @Override
     public int getNumObjectVertex() {
         return planeVertices.length / 3;
     }
   
     @Override
     public int getNumObjectIndex() {
         return planeIndices.length;
     }}
   

如果要更改图像的大小，请更改 PlaneVertices[] 中的值。

转到 src->main->java->com.qualcomm.vuforia.samples->VuforiaSamples->app->ImageTargets->ImageTargetRenderer.java

在 ImageTargetRenderer.java 中添加新类:

私有(private) TextPlane mTextPlane;

在 initRendering() 方法中初始化 mTextPlane

mTextPlane = new TextPlane();

将茶壶代码替换为新的文本平面代码:

替换这个:

GLES20.glVertexAttribPointer(vertexHandle, 3, GLES20.GL_FLOAT,
                        false, 0, mTeapot.getVertices());
                GLES20.glVertexAttribPointer(normalHandle, 3, GLES20.GL_FLOAT,
                        false, 0, mTeapot.getNormals());
                GLES20.glVertexAttribPointer(textureCoordHandle, 2,
                        GLES20.GL_FLOAT, false, 0, mTeapot.getTexCoords());

这样:

GLES20.glVertexAttribPointer(vertexHandle, 3, GLES20.GL_FLOAT,
                        false, 0, mTextPlane.getVertices());
                GLES20.glVertexAttribPointer(normalHandle, 3, GLES20.GL_FLOAT,
                        false, 0, mTextPlane.getNormals());
                GLES20.glVertexAttribPointer(textureCoordHandle, 2,
                        GLES20.GL_FLOAT, false, 0, mTextPlane.getTexCoords());

替换此:

GLES20.glDrawElements(GLES20.GL_TRIANGLES,
mTeapot.getNumObjectIndex()，GLES20.GL_UNSIGNED_SHORT，
mTeapot.getIndices());

这样:

GLES20.glDrawElements(GLES20.GL_TRIANGLES,
                            mTextPlane.getNumObjectIndex(), GLES20.GL_UNSIGNED_SHORT,
                            mTextPlane.getIndices());

尝试一下。应该可以!