我试图制作一个三角形和圆形的程序，其中三角形应该是透明的，并且圆圈需要在y轴上移动。我可以制作圆形和三角形，但不知道如何移动圆形。所以我做了一个正方形并将其设置在y轴上移动。我的问题是用移动制作圆圈的最佳方法是什么，我考虑将纹理添加到方形看起来像圆形，但它也会将纹理应用于三角形。任何帮助都意味着很多。谢谢！
这是我的代码：
public class MyGLRender implements GLSurfaceView.Renderer{
Context con;
private float[] mModelMatrix = new float[16];
private float[] mViewMatrix = new float[16];
private float[] projectionMatrix = new float[16];
private float[] mVPMatrix = new float[16];
private final FloatBuffer squareVert;
private final FloatBuffer mColor;
private FloatBuffer triangleVert;
private final FloatBuffer tColor;
private int mvpMatrixHandle;
private int positionHandle;
private int colorHandle;
ShortBuffer indexBuffer = null;
short[] indeces={
0,1,2,
0,3,2
};
float i;
public int smer;
public MyGLRender(Context con)
{
this.con=con;
i=0;
smer=1;
final float[] square={
0.0f, 1.0f, 0.0f,
0.0f,0.0f,0.0f,
1.0f,0.0f,0.0f,
1.0f,1.0f,0.0f,
};
final float[] triangle={
0.0f, 0.5f, 0.0f,
-0.5f, -0.5f, 0.0f,
0.5f, -0.5f, 0.0f
};
final float[] colors = {1,1,1,
1,1,1,
1,1,1,
1,1,1,
1,1,1,
1,1,1,
1,1,1,
1,1,1
};
final float[] colorsTr = {1,1,1,
1,1,1,
1,1,1,
1,1,1,
1,1,1,
1,1,1
};
squareVert = ByteBuffer.allocateDirect(square.length * 4)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
squareVert.put(square).position(0);
indexBuffer = ByteBuffer.allocateDirect(indeces.length * 2).order(ByteOrder.nativeOrder()).asShortBuffer();
indexBuffer.put(indeces).position(0);
mColor = ByteBuffer.allocateDirect(colors.length * 4)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
mColor.put(colors).position(0);
triangleVert = ByteBuffer.allocateDirect(square.length * 4)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
triangleVert.put(triangle).position(0);
indexBuffer = ByteBuffer.allocateDirect(indeces.length * 2).order(ByteOrder.nativeOrder()).asShortBuffer();
indexBuffer.put(indeces).position(0);
tColor = ByteBuffer.allocateDirect(colors.length * 4)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
tColor.put(colorsTr).position(0);
}
@Override
public void onSurfaceCreated(GL10 glUnused, EGLConfig config)
{
GLES20.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
Matrix.setLookAtM(mViewMatrix, 0, 0, 0, -5, 0, 0, 0, 0, 1, 0);
final String vertexShader =
"uniform mat4 un_MVPMatrix; \n"
+ "attribute vec4 attribute_Position; \n"
+ "attribute vec4 attribute_Color; \n"
+ "varying vec4 var_Color; \n"
+ "void main() \n"
+ "{ \n"
+ " var_Color = attribute_Color; \n"
+ " gl_Position = un_MVPMatrix \n"
+ " * attribute_Position; \n"
+ "} \n";
final String fragmentShader =
"precision mediump float; \n"
+ "varying vec4 var_Color; \n"
+ "void main() \n"
+ "{ \n"
+
" gl_FragColor = (length(gl_FragCoord.xy) < 0.5 ) \n" +
" ? vec4(1.0, 1.0, 1.0, 1.0)\n" +
" : vec4(0.5, 0.5, 0.5, 0.5); \n"
+ "} \n";
int vertexS = GLES20.glCreateShader(GLES20.GL_VERTEX_SHADER);
if (vertexS != 0)
{
GLES20.glShaderSource(vertexS, vertexShader);
GLES20.glCompileShader(vertexS);
final int[] compile_Status = new int[1];
GLES20.glGetShaderiv(vertexS, GLES20.GL_COMPILE_STATUS, compile_Status, 0);
}
if (vertexS == 0)
{
try {
throw new Exception("Vertex shader is not created.");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
int fragmentS = GLES20.glCreateShader(GLES20.GL_FRAGMENT_SHADER);
if (fragmentS != 0)
{
GLES20.glShaderSource(fragmentS, fragmentShader);
GLES20.glCompileShader(fragmentS);
final int[] compileStatus = new int[1];
GLES20.glGetShaderiv(fragmentS, GLES20.GL_COMPILE_STATUS, compileStatus, 0);
}
if (fragmentS == 0)
{
try {
throw new Exception("Fragment shader is not created.");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
int program = GLES20.glCreateProgram();
if (program != 0)
{
GLES20.glAttachShader(program, vertexS);
GLES20.glAttachShader(program, fragmentS);
GLES20.glBindAttribLocation(program, 0, "attribute_Position");
GLES20.glBindAttribLocation(program, 1, "attribute_Color");
GLES20.glLinkProgram(program);
final int[] linkStatus = new int[1];
GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
}
if (program == 0)
{
try {
throw new Exception("Program error");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
mvpMatrixHandle = GLES20.glGetUniformLocation(program, "un_MVPMatrix");
positionHandle = GLES20.glGetAttribLocation(program, "attribute_Position");
colorHandle = GLES20.glGetAttribLocation(program, "attribute_Color");
GLES20.glUseProgram(program);
}
public void onSurfaceChanged(GL10 glUnused, int width, int height)
{
GLES20.glViewport(0, 0, width, height);
final float ratio = (float) width / height;
final float left = -ratio;
final float right = ratio;
final float bottom = -1.0f;
final float top = 1.0f;
final float near = 1.0f;
final float far = 10.0f;
Matrix.frustumM(projectionMatrix, 0, left, right, bottom, top, near, far);
}
@Override
public void onDrawFrame(GL10 glUnused) {
GLES20.glClear(GLES20.GL_DEPTH_BUFFER_BIT | GLES20.GL_COLOR_BUFFER_BIT);
if (i > 1) {
smer = -1;
}
if (i < -1) {
smer = 1;
}
i += 0.05 * smer;
Matrix.setIdentityM(mModelMatrix, 0);
Matrix.translateM(mModelMatrix, 0, 0, i, 0.0f);
drawSqare(squareVert, indexBuffer);
Matrix.setIdentityM(mModelMatrix, 0);
Matrix.translateM(mModelMatrix,0, -1.5f, 0.0f, 0.0f);
drawSTriangle(triangleVert, indexBuffer);
GLES20.glDisable(GLES20.GL_CULL_FACE);
GLES20.glDisable(GLES20.GL_DEPTH_TEST);
GLES20.glEnable(GLES20.GL_BLEND);
GLES20.glBlendFunc(GLES20.GL_ONE, GLES20.GL_ONE);
Matrix.setIdentityM(mModelMatrix, 0);
Matrix.translateM(mModelMatrix, 0, -1.0f, 0.0f, -0.0f);
drawSTriangle(triangleVert, indexBuffer);
GLES20.glDisable(GLES20.GL_BLEND);
}
private void drawSqare(final FloatBuffer aTriangleBuffer,ShortBuffer sb)
{
aTriangleBuffer.position(0);
GLES20.glVertexAttribPointer(0, 3, GLES20.GL_FLOAT, false, 0, aTriangleBuffer);
GLES20.glEnableVertexAttribArray(positionHandle);
mColor.position(0);
GLES20.glVertexAttribPointer(colorHandle, 3, GLES20.GL_FLOAT, false, 0, mColor);
GLES20.glEnableVertexAttribArray(colorHandle);
Matrix.multiplyMM(mVPMatrix, 0, mViewMatrix, 0, mModelMatrix, 0);
Matrix.multiplyMM(mVPMatrix, 0, projectionMatrix, 0, mVPMatrix, 0);
GLES20.glUniformMatrix4fv(mvpMatrixHandle, 1, false, mVPMatrix, 0);
GLES20.glDrawElements(GLES20.GL_TRIANGLES, indeces.length, GLES20.GL_UNSIGNED_SHORT, indexBuffer);
}
private void drawSTriangle(final FloatBuffer fbb,ShortBuffer sbb)
{
fbb.position(0);
GLES20.glVertexAttribPointer(0, 3, GLES20.GL_FLOAT, false, 0, fbb);
GLES20.glEnableVertexAttribArray(positionHandle);
tColor.position(0);
GLES20.glVertexAttribPointer(colorHandle, 3, GLES20.GL_FLOAT, false,
0, tColor);
GLES20.glEnableVertexAttribArray(colorHandle);
Matrix.multiplyMM(mVPMatrix, 0, mViewMatrix, 0, mModelMatrix, 0);
Matrix.multiplyMM(mVPMatrix, 0, projectionMatrix, 0, mVPMatrix, 0);
GLES20.glUniformMatrix4fv(mvpMatrixHandle, 1, false, mVPMatrix, 0);
GLES20.glDrawElements(GLES20.GL_TRIANGLES, indeces.length, GLES20.GL_UNSIGNED_SHORT, indexBuffer);
}
}
答案 0 :(得分：0)
您可以按照Android提供的文档进行 OpenGL
选中adding Rotation or motion to view.
这是来自Android http://developer.android.com/shareables/training/OpenGLES.zip
的示例