【发布时间】：2014-03-13 09:12:59
【问题描述】：
我正在使用 GLKit 在 OpenGL ES 2.0 中创建一个矩形。这是可行的，我可以用纯色和渐变填充矩形。
现在我正在尝试用图像中的纹理填充它，这对我不起作用。
我在 glDrawElements 行收到 EXC_BAD_ACCESS code=1 错误。
这是我现在拥有的：
//设置GKLView
EAGLContext *context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
self.glkView = [[GLKView alloc] initWithFrame:self.bounds
context:context];
_glkView.opaque = NO;
_glkView.backgroundColor = [UIColor clearColor];
_glkView.delegate = self;
[self addSubview:_glkView];
//设置BaseEffect
self.effect = [[GLKBaseEffect alloc] init];
[EAGLContext setCurrentContext:_glkView.context];
GLKMatrix4 projectionMatrix = GLKMatrix4MakeOrtho(0, self.bounds.size.width, 0, self.bounds.size.height, 0.0, 1.0);
self.effect.transform.projectionMatrix = projectionMatrix;
GLKMatrix4 modelMatrix = GLKMatrix4Translate(GLKMatrix4Identity, 0.0, 0.0, -0.1);
self.effect.transform.modelviewMatrix = modelMatrix;
//加载图片
UIImage* image = ...
CGImageRef cgImage = image.CGImage;
NSError* error;
self.textureInfo = [GLKTextureLoader textureWithCGImage:cgImage options:nil error:&error];
if (error) {
NSLog(@"could not load texture");
}
if (_textureInfo) {
self.effect.texture2d0.envMode = GLKTextureEnvModeReplace;
self.effect.texture2d0.target = GLKTextureTarget2D;
self.effect.texture2d0.name = _textureInfo.name;
}
//绑定缓冲区
glGenBuffers(1, &_vertexBuffer);
glBindBuffer(GL_ARRAY_BUFFER, _vertexBuffer);
glGenBuffers(1, &_indexBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, _indexBuffer);
glEnableVertexAttribArray(GLKVertexAttribPosition);
glVertexAttribPointer (GLKVertexAttribPosition, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), (const GLvoid *) offsetof(Vertex, Position));
glEnableVertexAttribArray(GLKVertexAttribTexCoord0);
glVertexAttribPointer(GLKVertexAttribTexCoord0, 2, GL_FLOAT, GL_FALSE, 0, _currentData.texCoordinates);
//填充缓冲区
glBufferData(GL_ARRAY_BUFFER, (sizeof(Vertex) * _currentData.numberOfVertices), _currentData.vertices, GL_STATIC_DRAW);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, (sizeof(GLubyte) * _currentData.numberOfIndices), _currentData.indices, GL_STATIC_DRAW);
[self.effect prepareToDraw];
[self.glkView display];
//里面 - (void)glkView:(GLKView *)view drawInRect:(CGRect)rect;
glDrawElements(GL_TRIANGLE_STRIP, (sizeof(GLubyte) * _currentData.numberOfIndices), GL_UNSIGNED_BYTE, 0);
纹理坐标的数据是：
SimpleVertex* vertices1 = (SimpleVertex *)malloc(sizeof(SimpleVertex) * 4);
vertices1[0].Position[0] = 0.0;
vertices1[0].Position[1] = 0.0;
vertices1[1].Position[0] = 0.0;
vertices1[1].Position[1] = 1.0;
vertices1[2].Position[0] = 1.0;
vertices1[2].Position[1] = 1.0;
vertices1[3].Position[0] = 1.0;
vertices1[3].Position[1] = 0.0;
typedef struct
{
GLfloat Position[2];
}
SimpleVertex;
正如我所说，我确信矩形绘制正确。我可以通过填充渐变来检查它，它看起来很好。纹理加载器也正确加载了图像，我可以在调试器中检查这一点。
有人可以指出我在这里遗漏或做错了什么吗？
【问题讨论】：
标签： opengl-es opengl-es-2.0 glkit