Android OpenGL2.0 显示黑色纹理 [英] Android OpenGL2.0 showing black textures
问题描述
我正在尝试在 OpenGL2.0 中将纹理绘制到四边形上.到目前为止，我得到了四边形和所有东西，但纹理不存在 - 四边形都是黑色的.
I am trying to draw textures onto quads in OpenGL2.0. So far I got the quads to show up and everything, but the textures are not there - the quads are all black.
我的主要怀疑是我没有正确映射纹理 - 我的纹理 不是 2 的幂，也不是正方形 - 它们的宽度在字段中mWidth 和它们在 mRowHeight 中的高度.
My main suspicion is that i'm not mapping the textures correctly - my textures are not powers of 2, nor are they square - their width is in the field mWidth and their height in mRowHeight.
四边形绘制在垂直列表中，这是通过平移矩阵完成的.
The quads are drawn in a vertical list, which is done with a translate matrix.
如果有人能解决这个问题，我将非常感激，因为我很绝望！
I'll be very grateful if anyone can go over this cause I'm desperate!
相关代码如下:
初始化缓冲区:
void initBuffers() {
float r = (float) mRowHeight / (mHeight / 2f);
ByteBuffer bb;
float[] bounds = { // X Y Z
/* 0 - TL */-1f, 1f, 0f,
/* 1 - BL */-1f, 1 - r, 0f,
/* 2 - BR */ 1f, 1 - r, 0f,
/* 3 - TR */ 1f, 1f, 0f };
bb = ByteBuffer.allocateDirect(bounds.length * 4);
bb.order(ByteOrder.nativeOrder());
mVertBuffer = bb.asFloatBuffer();
mVertBuffer.put(bounds).position(0);
short[] indices = { 0, 1, 2, 0, 2, 3 };
bb = ByteBuffer.allocateDirect(indices.length * 2);
bb.order(ByteOrder.nativeOrder());
mIndBuffer = bb.asShortBuffer();
mIndBuffer.put(indices).position(0);
float[] texture = {
/* 0 - BL */-1f, 1f,
/* 1 - TL */-1f, 1 - r,
/* 2 - BR */1f, 1 - r,
/* 3 - TR */1f, 1f };
bb = ByteBuffer.allocateDirect(texture.length * 4);
bb.order(ByteOrder.nativeOrder());
mTexBuffer = bb.asFloatBuffer();
mTexBuffer.put(texture).position(0);
}
画框:
@Override
public void drawFrame() {
long startTime = System.currentTimeMillis();
if (!mLayoutComplete) {
return;
}
final float halfw = mHeight / 2f;
final int rowHeight = mRowHeight;
final float r = (float) rowHeight / halfw;
int i = mFirstRow;
final float initial = (float) ((i * rowHeight) - mScroll) / halfw;
Matrix.setIdentityM(mTMatrix, 0);
Matrix.translateM(mTMatrix, 0, 0, -initial, 0);
GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT,
false, 0, mVertBuffer);
GLES20.glEnableVertexAttribArray(maPositionHandle);
final int l = mLastRow;
for (; i <= l; i++) {
ThumbRow thr = mCache.get(i);
if (thr != null) {
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
if (thr.mDirty) {
thr.loadTexture(null, null);
thr.mDirty = false;
} else {
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, thr.mRow + 1);
}
GLES20.glUniform1i(msTextureHandle, 0);
GLES20.glVertexAttribPointer(maTextureHandle, 2,
GLES20.GL_FLOAT, false, 0, mTexBuffer);
GLES20.glEnableVertexAttribArray(maTextureHandle);
GLES20.glUniformMatrix4fv(muTMatrixHandle, 1, false,
mTMatrix, 0);
GLES20.glDrawElements(GLES20.GL_TRIANGLES, 6,
GLES20.GL_UNSIGNED_SHORT, mIndBuffer);
Log.i(TAG, GLES20.glGetProgramInfoLog(mProgram));
}
Matrix.translateM(mTMatrix, 0, 0, -r, 0); // Shift drawing
// window to next
// row.
}
GLES20.glDisableVertexAttribArray(maPositionHandle);
GLES20.glDisableVertexAttribArray(maTextureHandle);
Log.d(TAG, "onDrawFrame(): "
+ (System.currentTimeMillis() - startTime));
}
加载纹理:
public void loadTexture(GL10 gl, Context c) {
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mRow + 1);
// Create Nearest Filtered Texture
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D,
GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D,
GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);
// Different possible texture parameters, e.g.
// GLES20.GL_CLAMP_TO_EDGE
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D,
GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_REPEAT);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D,
GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_REPEAT);
Bitmap bitmap = mBitmap;
if (bitmap == null) {
bitmap = mEmptyBitmap;
}
GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
}
顶点着色器:
uniform mat4 uTMatrix;
uniform mat4 uMVPMatrix;
attribute vec4 aPosition;
attribute vec2 aTextureCoord;
varying vec2 vTextureCoord;
void main() {
gl_Position = uMVPMatrix * uTMatrix * aPosition;
vTextureCoord = aTextureCoord;
}
片段着色器:
precision mediump float;
varying vec2 vTextureCoord;
uniform sampler2D sTexture;
void main() {
gl_FragColor = texture2D(sTexture, vTextureCoord);
}
任何帮助将不胜感激.
推荐答案
这是 OpenGL ES 2.0 上一个很常见的纹理问题，过去曾让我很头疼.
This is a quite common issue of texturing on OpenGL ES 2.0 which caused a lot of headache to me in the past.
在OpenGL ES 2.0中，在没有2个纹理的情况下，包裹模式只能是GL_CLAMP_TO_EDGE.
In OpenGL ES 2.0, in caso of no-power of 2 textures, the wrap mode can only be GL_CLAMP_TO_EDGE.
您可以使用的过滤器也有一些限制，只能是 GL_NEAREST 或 GL_LINEAR(换句话说，没有 MIPMAPPING)
There are restrictions as well on the filter you can use which can be only GL_NEAREST or GL_LINEAR (in other words no MIPMAPPING)
简单来说，检查你的 loadtexture 函数，将这两行代码更改为:
In simple words, checking you loadtexture function, change these 2 code lines from:
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D,
GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_REPEAT);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D,
GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_REPEAT);
到
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D,
GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D,
GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_CLAMP_TO_EDGE);
我希望这能解决问题，让我知道 :)
I hope this fix the problem, let me know :)
毛里齐奥·贝内德蒂
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