私は、OpenGLES 2.0android4.1で立方体を描画して回転させる単純なプロジェクトに取り組んでいます。しかし、描かれた形はt cube. and it is rotating a axis that i wasn想定されていませんでした。カメラ空間でX、Y軸を回転させていると思います。アドバイスありがとうございます。
public float mAngleX;
public float mAngleY;
private Quadrat quad;
private final float[] MVPMatrix = new float[16];
private final float[] projectionMatrix = new float[16];
private final float[] mVMatrix = new float[16];
private final float[] rotationMatrix = new float[16];
public MyRenderer(){
mAngleX = 0;
mAngleY = 0;
}
// @Override
public void onSurfaceCreated(GL10 unused, EGLConfig config){
// Set the background frame color
GLES20.glClearColor(0.5f, 0.2f, 0.1f, 1.0f);
Matrix.setLookAtM(mVMatrix, 0, 0.0f, 0.0f, -5.0f, 0f, 0f, 1f, 0f, 1.0f, 0.0f);
quad = new Quadrat();
}
// @Override
public void onSurfaceChanged(GL10 unused, int width, int height){
GLES20.glViewport(0, 0, width, height);
float ratio = (float) width / height;
Matrix.perspectiveM(projectionMatrix, 0, 45.0f, ratio, 1, 9);
}
//@Override
public void onDrawFrame(GL10 unused) {
// Draw background color
GLES20.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
Matrix.setRotateM(rotationMatrix, 0, mAngleX, 0.0f, 1.0f, 0.0f);
Matrix.multiplyMM(MVPMatrix, 0, rotationMatrix, 0, MVPMatrix, 0);
Matrix.setRotateM(rotationMatrix, 0, mAngleY, 1.0f, 0.0f, 0.0f);
Matrix.multiplyMM(MVPMatrix, 0, rotationMatrix, 0, MVPMatrix, 0);
Matrix.multiplyMM(MVPMatrix, 0, projectionMatrix, 0, mVMatrix, 0);
quad.draw(MVPMatrix, mVMatrix);
}
public static int loadShader(int type, String shaderCode){
int shader = GLES20.glCreateShader(type);
// add the source code to the shader and compile it
GLES20.glShaderSource(shader, shaderCode);
GLES20.glCompileShader(shader);
return shader;
}
}
quadratクラスは以下のとおりです。
class Quadrat {
private final String vertexShaderCode =
"uniform mat4 uMVPMatrix;\n" +
"uniform mat4 uMVMatrix;\n" +
"uniform vec3 uLightPos;\n" +
"attribute vec4 aPosition;\n" +
"attribute vec4 aColor;\n" +
"attribute vec4 aNormal;\n" +
"varying vec4 vColor;\n" +
"void main() {\n" +
"gl_Position = uMVPMatrix * aPosition;\n" +
"}\n";
private final String fragmentShaderCode =
"precision mediump float;\n" +
"varying vec4 vColor;\n" +
"void main() {\n" +
"gl_FragColor = vec4(1.0, 0.9, 0.4, 1.0);\n" +
"}\n";
private final FloatBuffer vertexBuffer;
private final int mProgram;
private int mPositionHandle;
private int muMVPMatrixHandle;
private int muLightPosHandle;
private int muMVMatrixHandle;
// number of coordinates per vertex in this array
static final int COORDS_PER_VERTEX = 3;
static float quadrateCoords[] = { // in counterclockwise order:
// front
-0.5f, -0.5f, 0.5f,
0.5f, -0.5f, 0.5f,
-0.5f, 0.5f, 0.5f,
0.5f, 0.5f, 0.5f,
// back
-0.5f, -0.5f, -0.5f,
0.5f, -0.5f, -0.5f,
-0.5f, 0.5f, -0.5f,
0.5f, 0.5f, -0.5f,
// left
-0.5f, -0.5f, 0.5f,
-0.5f, -0.5f, -0.5f,
-0.5f, 0.5f, 0.5f,
-0.5f, 0.5f, -0.5f,
// right
0.5f, -0.5f, 0.5f,
0.5f, -0.5f, -0.5f,
0.5f, 0.5f, 0.5f,
0.5f, 0.5f, -0.5f,
// up
-0.5f, 0.5f, 0.5f,
0.5f, 0.5f, 0.5f,
-0.5f, 0.5f, -0.5f,
0.5f, 0.5f, -0.5f,
// bottom
-0.5f, -0.5f, 0.5f,
0.5f, -0.5f, 0.5f,
-0.5f, -0.5f, -0.5f,
0.5f, -0.5f, -0.5f
};
private final int vertexStride = COORDS_PER_VERTEX * 4; // bytes per vertex
public Quadrat() {
// initialize vertex byte buffer for shape coordinates
ByteBuffer bb = ByteBuffer.allocateDirect(quadrateCoords.length * 4);
// use the device hardware's native byte order
bb.order(ByteOrder.nativeOrder());
// create a floating point buffer from the ByteBuffer
vertexBuffer = bb.asFloatBuffer();
// add the coordinates to the FloatBuffer
vertexBuffer.put(quadrateCoords);
vertexBuffer.position(0);
// prepare shaders and OpenGL program
int vertexShader = MyRenderer.loadShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);
int fragmentShader = MyRenderer.loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentShaderCode);
mProgram = GLES20.glCreateProgram(); // create empty OpenGL Program
GLES20.glAttachShader(mProgram, vertexShader); // add the vertex shader to program
GLES20.glAttachShader(mProgram, fragmentShader); // add the fragment shader to program
GLES20.glLinkProgram(mProgram); // create OpenGL program executables
}
public void draw(float[] mvpMatrix, float[] mVMatrix) {
// Add program to OpenGL environment
GLES20.glUseProgram(mProgram);
// get handle to vertex shader's aPosition member
mPositionHandle = GLES20.glGetAttribLocation(mProgram, "aPosition");
// Enable a handle to the triangle vertices
// Prepare the triangle coordinate data
GLES20.glEnableVertexAttribArray(mPositionHandle);
GLES20.glVertexAttribPointer(mPositionHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, vertexStride, vertexBuffer);
VertexStride、vertexBuffer2）;
VertexStride、vertexBuffer3）;
muMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mvpMatrix, 0);
muMVMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVMatrix");
GLES20.glUniformMatrix4fv(muMVMatrixHandle, 1, false, mVMatrix, 0);
muLightPosHandle = GLES20.glGetUniformLocation(mProgram, "uLightPos");
GLES20.glUniform3f(muLightPosHandle, 10.0f, 10.0f, 15.0f);
// Front
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
// Back
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 4, 4);
// Left
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 8, 4);
// Right
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 12, 4);
// Top
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 16, 4);
// Right
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 20, 4);
// Disable vertex array
GLES20.glDisableVertexAttribArray(mPositionHandle);
}
}