void glActiveTexture(GLenum texture)
{
#if QT_VERSION < QT_VERSION_CHECK(5, 0, 0)
#ifndef QT_OPENGL_ES
if (!qtav_glActiveTexture)
qtavResolveActiveTexture();
if (!qtav_glActiveTexture)
return;
qtav_glActiveTexture(texture);
#else
::glActiveTexture(texture);
#endif //QT_OPENGL_ES
#else
QOpenGLContext::currentContext()->functions()->glActiveTexture(texture);
#endif
}
void GLWidgetRenderer::drawFrame()
{
DPTR_D(GLWidgetRenderer);
QRect roi = realROI();
d.upload(roi);
// shader program may not ready before upload
if (d.hasGLSL) {
#if NO_QGL_SHADER
glUseProgram(d.program); //for glUniform
#else
d.shader_program->bind();
#endif //NO_QGL_SHADER
}
glDisable(GL_DEPTH_TEST);
const int nb_planes = d.video_frame.planeCount(); //number of texture id
// all texture ids should be binded when renderering even for packed plane!
for (int i = 0; i < nb_planes; ++i) {
glActiveTexture(GL_TEXTURE0 + i);
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, d.textures[i]); //we've bind 0 after upload()
// use glUniform1i to swap planes. swap uv: i => (3-i)%3
// TODO: in shader, use uniform sample2D u_Texture[], and use glUniform1iv(u_Texture, 3, {...})
#if NO_QGL_SHADER
glUniform1i(d.u_Texture[i], i);
#else
d.shader_program->setUniformValue(d.u_Texture[i], (GLint)i);
#endif
}
if (nb_planes < d.u_Texture.size()) {
for (int i = nb_planes; i < d.u_Texture.size(); ++i) {
#if NO_QGL_SHADER
glUniform1i(d.u_Texture[i], nb_planes - 1);
#else
d.shader_program->setUniformValue(d.u_Texture[i], (GLint)(nb_planes - 1));
#endif
}
}
//TODO: compute kTexCoords only if roi changed
#if ROI_TEXCOORDS
/*!
tex coords: ROI/frameRect()*effective_tex_width_ratio
*/
const GLfloat kTexCoords[] = {
(GLfloat)roi.x()*(GLfloat)d.effective_tex_width_ratio/(GLfloat)d.video_frame.width(), (GLfloat)roi.y()/(GLfloat)d.video_frame.height(),
(GLfloat)(roi.x() + roi.width())*(GLfloat)d.effective_tex_width_ratio/(GLfloat)d.video_frame.width(), (GLfloat)roi.y()/(GLfloat)d.video_frame.height(),
(GLfloat)(roi.x() + roi.width())*(GLfloat)d.effective_tex_width_ratio/(GLfloat)d.video_frame.width(), (GLfloat)(roi.y()+roi.height())/(GLfloat)d.video_frame.height(),
(GLfloat)roi.x()*(GLfloat)d.effective_tex_width_ratio/(GLfloat)d.video_frame.width(), (GLfloat)(roi.y()+roi.height())/(GLfloat)d.video_frame.height(),
};
/// glVertexAttribPointer(d.a_TexCoords, 2, GL_FLOAT, GL_FALSE, 0, kTexCoords);
/// glEnableVertexAttribArray(d.a_TexCoords);
#else
const GLfloat kTexCoords[] = {
0, 0,
1, 0,
1, 1,
0, 1,
};
#endif //ROI_TEXCOORDS
#ifndef QT_OPENGL_ES_2
//GL_XXX may not defined in ES2. so macro is required
if (!d.hasGLSL) {
//qpainter will reset gl state, so need glMatrixMode and clear color(in drawBackground())
//TODO: study what state will be reset
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glPushMatrix();
d.setupAspectRatio(); //TODO: can we avoid calling this every time but only in resize event?
glVertexPointer(2, GL_FLOAT, 0, kVertices);
glEnableClientState(GL_VERTEX_ARRAY);
glTexCoordPointer(2, GL_FLOAT, 0, kTexCoords);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glDisableClientState(GL_VERTEX_ARRAY);
glPopMatrix();
}
#endif //QT_OPENGL_ES_2
if (d.hasGLSL) {
d.setupAspectRatio(); //TODO: can we avoid calling this every time but only in resize event?
//qpainter need. TODO: VBO?
#if NO_QGL_SHADER
glVertexAttribPointer(d.a_Position, 2, GL_FLOAT, GL_FALSE, 0, kVertices);
glEnableVertexAttribArray(d.a_Position);
glVertexAttribPointer(d.a_TexCoords, 2, GL_FLOAT, GL_FALSE, 0, kTexCoords);
glEnableVertexAttribArray(d.a_TexCoords);
#else
d.shader_program->setAttributeArray(d.a_Position, GL_FLOAT, kVertices, 2);
d.shader_program->enableAttributeArray(d.a_Position);
d.shader_program->setAttributeArray(d.a_TexCoords, GL_FLOAT, kTexCoords, 2);
d.shader_program->enableAttributeArray(d.a_TexCoords);
#endif
/*
* in Qt4 QMatrix4x4 stores qreal (double), while GLfloat may be float
* QShaderProgram deal with this case. But compares sizeof(QMatrix4x4) and (GLfloat)*16
* which seems not correct because QMatrix4x4 has a flag var
*/
GLfloat *mat = (GLfloat*)d.colorTransform.matrixRef().data();
GLfloat glm[16];
#if QT_VERSION < QT_VERSION_CHECK(5, 0, 0)
if (sizeof(qreal) != sizeof(GLfloat)) {
#else
if (sizeof(float) != sizeof(GLfloat)) {
#endif
d.colorTransform.matrixData(glm);
mat = glm;
}
//QMatrix4x4 stores value in Column-major order to match OpenGL. so transpose is not required in glUniformMatrix4fv
#if NO_QGL_SHADER
glUniformMatrix4fv(d.u_colorMatrix, 1, GL_FALSE, mat);
#else
d.shader_program->setUniformValue(d.u_colorMatrix, d.colorTransform.matrixRef());
#endif
glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
#if NO_QGL_SHADER
glUseProgram(0);
glDisableVertexAttribArray(d.a_TexCoords);
glDisableVertexAttribArray(d.a_Position);
#else
d.shader_program->release();
d.shader_program->disableAttributeArray(d.a_TexCoords);
d.shader_program->disableAttributeArray(d.a_Position);
#endif
}
for (int i = 0; i < d.textures.size(); ++i) {
//glActiveTexture: gl functions apply on texture i
glActiveTexture(GL_TEXTURE0 + i);
glDisable(GL_TEXTURE_2D);
}
}
void GLWidgetRenderer::initializeGL()
{
DPTR_D(GLWidgetRenderer);
makeCurrent();
//const QByteArray extensions(reinterpret_cast<const char *>(glGetString(GL_EXTENSIONS)));
d.hasGLSL = QGLShaderProgram::hasOpenGLShaderPrograms();
qDebug("OpenGL version: %d.%d hasGLSL: %d", format().majorVersion(), format().minorVersion(), d.hasGLSL);
#if QTAV_HAVE(QGLFUNCTIONS)
initializeGLFunctions();
d.initializeGLFunctions();
#endif //QTAV_HAVE(QGLFUNCTIONS)
qtavResolveActiveTexture();
glEnable(GL_TEXTURE_2D);
if (!d.hasGLSL) {
#ifndef QT_OPENGL_ES_2
glShadeModel(GL_SMOOTH); //setupQuality?
glClearDepth(1.0f);
#endif //QT_OPENGL_ES_2
}
else {
d.initWithContext(context());
}
glClearColor(0.0, 0.0, 0.0, 0.0);
d.setupQuality();
}
