/// 应用于矩形
CZRect CZAffineTransform::applyToRect(CZRect & rect_)
{
CZ2DPoint a = CZ2DPoint(rect_.getMinX(), rect_.getMinY());
CZ2DPoint b = CZ2DPoint(rect_.getMaxX(), rect_.getMinY());
CZ2DPoint c = CZ2DPoint(rect_.getMinX(), rect_.getMaxY());
CZ2DPoint d = CZ2DPoint(rect_.getMaxX(), rect_.getMaxY());
a = this->applyTo2DPoint(a);
b = this->applyTo2DPoint(b);
c = this->applyTo2DPoint(c);
d = this->applyTo2DPoint(d);
float minX = CZUtil::Min(a.x, CZUtil::Min(b.x, CZUtil::Min(c.x,d.x)));
float maxX = CZUtil::Max(a.x, CZUtil::Max(b.x, CZUtil::Max(c.x,d.x)));
float minY = CZUtil::Min(a.y, CZUtil::Min(b.y, CZUtil::Min(c.y,d.y)));
float maxY = CZUtil::Max(a.y, CZUtil::Max(b.y, CZUtil::Max(c.y,d.y)));
return CZRect(minX,minY, maxX-minX, maxY-minY);
}
/// 绘制矩形
void CZUtil::drawRect(const CZRect &rect, const CZAffineTransform &transform)
{
CZ2DPoint corners[4];
GLuint vbo = 0;
corners[0] = rect.origin;
corners[1] = CZ2DPoint(rect.getMaxX(), rect.getMinY());
corners[2] = CZ2DPoint(rect.getMaxX(), rect.getMaxY());
corners[3] = CZ2DPoint(rect.getMinX(), rect.getMaxY());
for (int i = 0; i < 4; i++)
{
corners[i] = transform.applyTo2DPoint(corners[i]);
}
const GLfloat quadVertices[] =
{
corners[0].x, corners[0].y, 0.0, 0.0,
corners[1].x, corners[1].y, 1.0, 0.0,
corners[3].x, corners[3].y, 0.0, 1.0,
corners[2].x, corners[2].y, 1.0, 1.0,
};
// create, bind, and populate VBO
glGenBuffers(1, &vbo);
glBindBuffer(GL_ARRAY_BUFFER, vbo);
glBufferData(GL_ARRAY_BUFFER, sizeof(GLfloat) * 16, quadVertices, GL_STATIC_DRAW);
// set up attrib pointers
glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(GLfloat) * 4, (void*)0);
glEnableVertexAttribArray(0);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, sizeof(GLfloat) * 4, (void*)8);
glEnableVertexAttribArray(1);
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
glDeleteBuffers(1, &vbo);
glBindBuffer(GL_ARRAY_BUFFER, 0);
}
/// 绘制数据
///
/// 以最小粒度的离散点(points_)为中心，形成小矩形，委托render绘制，并将此矩形数据返回。
///
CZRect CZPath::drawData()
{
size_t iPointSize = points.size();
CZRect dataBounds = CZRect(0.0f,0.0f,0.0f,0.0f);
if (iPointSize <= 0) return dataBounds;
vertexData *vertexD = new vertexData[iPointSize * 4 + (iPointSize - 1) * 2];
int n = 0;
for (int i = 0; i < iPointSize; i++)
{
CZ2DPoint result = points[i];
float angle = angles[i];
float size = sizes[i] / 2;
float alpha = alphas[i];
// get the four corners of the dot
CZRect rect = CZRect(result.x - size, result.y - size, size*2, size*2);
CZ2DPoint a = CZ2DPoint(rect.getMinX(), rect.getMinY());
CZ2DPoint b = CZ2DPoint(rect.getMaxX(), rect.getMinY());
CZ2DPoint c = CZ2DPoint(rect.getMinX(), rect.getMaxY());
CZ2DPoint d = CZ2DPoint(rect.getMaxX(), rect.getMaxY());
// rotate the dot
CZ2DPoint center = rect.getCenter();
CZAffineTransform t = CZAffineTransform::makeFromTranslation(center.x, center.y);
t.rotate(angle);
t.translate(-center.x, -center.y);
a = t.applyTo2DPoint(a);
b = t.applyTo2DPoint(b);
c = t.applyTo2DPoint(c);
d = t.applyTo2DPoint(d);
// update the bounds box of data
CZRect boxBounds = t.applyToRect(rect);
dataBounds = dataBounds.unionWith(boxBounds.expandToIntergral());
if (n != 0) {
// dup 1st vertex
vertexD[n].x = a.x;
vertexD[n].y = a.y;
vertexD[n].s = 0;
vertexD[n].t = 0;
vertexD[n].a = alpha;
n++;
}
vertexD[n].x = a.x;
vertexD[n].y = a.y;
vertexD[n].s = 0;
vertexD[n].t = 0;
vertexD[n].a = alpha;
n++;
vertexD[n].x = b.x;
vertexD[n].y = b.y;
vertexD[n].s = 1;
vertexD[n].t = 0;
vertexD[n].a = alpha;
n++;
vertexD[n].x = c.x;
vertexD[n].y = c.y;
vertexD[n].s = 0;
vertexD[n].t = 1;
vertexD[n].a = alpha;
n++;
vertexD[n].x = d.x;
vertexD[n].y = d.y;
vertexD[n].s = 1;
vertexD[n].t = 1;
vertexD[n].a = alpha;
n++;
if (i != (iPointSize - 1)) {
// dup last vertex
vertexD[n].x = d.x;
vertexD[n].y = d.y;
vertexD[n].s = 1;
vertexD[n].t = 1;
vertexD[n].a = alpha;
n++;
}
}
#ifdef USE_OPENGL_ES
glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(vertexData), &vertexD[0].x);
glEnableVertexAttribArray(0);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_TRUE, sizeof(vertexData), &vertexD[0].s);
glEnableVertexAttribArray(1);
glVertexAttribPointer(2, 1, GL_FLOAT, GL_TRUE, sizeof(vertexData), &vertexD[0].a);
glEnableVertexAttribArray(2);
glDrawArrays(GL_TRIANGLE_STRIP, 0, n);
#endif
#ifdef USE_OPENGL
/* // 对于opengl属性数组形式， 顶点位置必须通过以下方式导入
glEnableClientState (GL_VERTEX_ARRAY);
glVertexPointer(2, GL_FLOAT , sizeof(vertexData), &data[0].x);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_TRUE, sizeof(vertexData), &data[0].s);
glEnableVertexAttribArray(1);
glVertexAttribPointer(2, 1, GL_FLOAT, GL_TRUE, sizeof(vertexData), &data[0].a);
glEnableVertexAttribArray(2);
/// 绘制
glDrawArrays(GL_TRIANGLE_STRIP,0,n);
*/
GLuint mVertexBufferObject, mTexCoordBufferObject, mAttributeBufferObject;
// 装载顶点
glGenBuffers(1, &mVertexBufferObject);
glBindBuffer(GL_ARRAY_BUFFER, mVertexBufferObject);
glBufferData(GL_ARRAY_BUFFER, n * sizeof(vertexData), &vertexD[0].x, GL_STREAM_DRAW);
// 装载纹理
glGenBuffers(1, &mTexCoordBufferObject);
glBindBuffer(GL_ARRAY_BUFFER, mTexCoordBufferObject);
glBufferData(GL_ARRAY_BUFFER, n * sizeof(vertexData), &vertexD[0].s, GL_STREAM_DRAW);
// 装载属性
glGenBuffers(1, &mAttributeBufferObject);
glBindBuffer(GL_ARRAY_BUFFER, mAttributeBufferObject);
glBufferData(GL_ARRAY_BUFFER, n * sizeof(vertexData), &vertexD[0].a, GL_STREAM_DRAW);
// 绑定顶点
glBindBuffer(GL_ARRAY_BUFFER, mVertexBufferObject);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0,2,GL_FLOAT, GL_FALSE, sizeof(vertexData),0);
// 绑定纹理
glBindBuffer(GL_ARRAY_BUFFER, mTexCoordBufferObject);
glEnableVertexAttribArray(1);
glVertexAttribPointer(1,2,GL_FLOAT, GL_TRUE, sizeof(vertexData),0);
// 绑定属性
glBindBuffer(GL_ARRAY_BUFFER, mAttributeBufferObject);
glEnableVertexAttribArray(2);
glVertexAttribPointer(2, 1, GL_FLOAT, GL_TRUE, sizeof(vertexData), NULL);
/// 绘制
glDrawArrays(GL_TRIANGLE_STRIP,0,n);
glDisableVertexAttribArray(0);
glDisableVertexAttribArray(1);
glDisableVertexAttribArray(2);
glBindBuffer(GL_ARRAY_BUFFER, 0);
/// 消除
glDeleteBuffers(1, &mVertexBufferObject);
glDeleteBuffers(1, &mTexCoordBufferObject);
glDeleteBuffers(1, &mAttributeBufferObject);
#endif
CZCheckGLError();
delete [] vertexD;
return dataBounds;
}