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[英]Qt/QML/OpenGL: Z-ordering doesn't work with semi-transparent items with OpenGL under QML
[英]OpenGL in QT QML, can't update my image on screen
為了將OpenGL與QML結合使用,我完全按照此處所述創建了OpenGlVideoQtQuick
和OpenGlVideoQtQuickRenderer
類。 唯一的區別是,我添加了updateData()
函數來更新緩沖區,而在此示例中,在屏幕上繪制了靜態圖像。
這是OpenGlVideoQtQuickRenderer
的關鍵部分,即paint
功能
void OpenGlVideoQtQuickRenderer::paint()
{
if (this->firstRun) {
this->firstRun = false;
//qDebug() << "initializeGL";
std::cout << "initializing gl" << std::endl;
//初始化opengl (QOpenGLFunctions繼承)函數
initializeOpenGLFunctions();
datas[0] = new unsigned char[width*height]; //Y
datas[1] = new unsigned char[width*height/4]; //U
datas[2] = new unsigned char[width*height/4]; //V
//this->m_F = QOpenGLContext::currentContext()->functions();
//program加載shader(頂點和片元)腳本
//片元(像素)
std::cout << program.addShaderFromSourceCode(QOpenGLShader::Fragment, tString2) << std::endl;
//頂點shader
std::cout << program.addShaderFromSourceCode(QOpenGLShader::Vertex, vString2) << std::endl;
//設置頂點坐標的變量
program.bindAttributeLocation("vertexIn",A_VER);
//設置材質坐標
program.bindAttributeLocation("textureIn",T_VER);
//編譯shader
std::cout << "program.link() = " << program.link() << std::endl;
}
program.bind();
//傳遞頂點和材質坐標
//頂點
static const GLfloat ver[] = {
-1.0f,-1.0f,
1.0f,-1.0f,
-1.0f, 1.0f,
1.0f,1.0f
};
//材質
static const GLfloat tex[] = {
0.0f, 1.0f,
1.0f, 1.0f,
0.0f, 0.0f,
1.0f, 0.0f
};
//頂點
glVertexAttribPointer(A_VER, 2, GL_FLOAT, 0, 0, ver);
glEnableVertexAttribArray(A_VER);
//材質
glVertexAttribPointer(T_VER, 2, GL_FLOAT, 0, 0, tex);
glEnableVertexAttribArray(T_VER);
//glUseProgram(&program);
//從shader獲取材質
unis[0] = program.uniformLocation("tex_y");
unis[1] = program.uniformLocation("tex_u");
unis[2] = program.uniformLocation("tex_v");
//創建材質
glGenTextures(3, texs);
//Y
glBindTexture(GL_TEXTURE_2D, texs[0]);
//放大過濾,線性插值 GL_NEAREST(效率高,但馬賽克嚴重)
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
//創建材質顯卡空間
glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, 0);
//U
glBindTexture(GL_TEXTURE_2D, texs[1]);
//放大過濾,線性插值
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
//創建材質顯卡空間
glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, width/2, height / 2, 0, GL_RED, GL_UNSIGNED_BYTE, 0);
//V
glBindTexture(GL_TEXTURE_2D, texs[2]);
//放大過濾,線性插值
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
//創建材質顯卡空間
glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, width / 2, height / 2, 0, GL_RED, GL_UNSIGNED_BYTE, 0);
///分配材質內存空間
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, texs[0]); //0層綁定到Y材質
//修改材質內容(復制內存內容)
glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, GL_RED, GL_UNSIGNED_BYTE, datas[0]);
//與shader uni遍歷關聯
glUniform1i(unis[0], 0);
glActiveTexture(GL_TEXTURE0+1);
glBindTexture(GL_TEXTURE_2D, texs[1]); //1層綁定到U材質
//修改材質內容(復制內存內容)
glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width/2, height / 2, GL_RED, GL_UNSIGNED_BYTE, datas[1]);
//與shader uni遍歷關聯
glUniform1i(unis[1],1);
glActiveTexture(GL_TEXTURE0+2);
glBindTexture(GL_TEXTURE_2D, texs[2]); //2層綁定到V材質
//修改材質內容(復制內存內容)
glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width / 2, height / 2, GL_RED, GL_UNSIGNED_BYTE, datas[2]);
//與shader uni遍歷關聯
glUniform1i(unis[2], 2);
glDrawArrays(GL_TRIANGLE_STRIP,0,4);
//this->update();
// Not strictly needed for this example, but generally useful for when
// mixing with raw OpenGL.
m_window->resetOpenGLState();//COMMENT OR NOT?
}
這是我用來更新要繪制的緩沖區的函數:
void OpenGlVideoQtQuickRenderer::updateData(unsigned char**data)
{
std::cout << "updating data..." << std::endl;
memcpy(datas[0], data[0], width*height);
memcpy(datas[1], data[1], width*height/4);
memcpy(datas[2], data[2], width*height/4);
//I should update something here
}
我唯一的問題是我看到函數updateData被新數據調用,因此緩沖區正在更新。 但是,屏幕繼續在其初始位置(綠色)。 我確定必須有一個必須調用的函數來更新所有內容。
我還有什么需要在updateData
中updateData
嗎?
我嘗試了各種更新數據的方法,但是圖像仍然不會更新
this->openGlVideoQtQuickRenderer->paint();
if (this->openGlVideoQtQuick->window()) {
std::cout << "window update" << std::endl;
this->openGlVideoQtQuick->update();
this->openGlVideoQtQuick->window()->update();
}
但是,如果我調整屏幕大小,可以看到圖像的時間不到一秒鍾,並且圖像消失了。
如果有人想看一看的完整代碼: https : //github.com/lucaszanella/orwell/blob/2aff3b97abd88e6ec2980856718e1c8302d41616/OpenGlVideoQtQuick.cpp#L117
好吧,我試圖像您在上面看到的那樣更新窗口,但是唯一起作用的是
connect(window(), &QQuickWindow::afterRendering, this, &OpenGlVideoQtQuick::update, Qt::DirectConnection);
(而且我必須從上方關閉該更新窗口才能使此窗口正常工作)
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