Fix rendering of textures with alpha channel

doc/Changelog.md

@@ -3,6 +3,8 @@ Changelog {#changelog}
 
 # Release 1.5 (git master)
 
+* [270](https://github.com/BlueBrain/Tide/pull/270):
+ Fix rendering of contents with alpha channel + "transparent windows" option.
 * [269](https://github.com/BlueBrain/Tide/pull/269):
  Fix segfault with TIFF pyramids in grayscale + alpha (2 bytes per pixel).
 * [268](https://github.com/BlueBrain/Tide/pull/268):

tide/core/data/FFMPEGVideoStream.cpp

@@ -358,6 +358,8 @@ void FFMPEGVideoStream::_generateSeekingParameters()
  const auto den = int64_t(timeBase.num) * AV_TIME_BASE;
  duration = av_rescale(_avFormatContext.duration, num, den);
  }
+ if (duration <= 0)
+ throw std::runtime_error("cannot determine movie duration");
 
  // Estimate number of frames if unavailable
  _numFrames = _videoStream->nb_frames;

tide/core/scene/MovieContent.cpp

@@ -43,6 +43,8 @@
 
 #include "data/FFMPEGMovie.h"
 
+#include "utils/log.h"
+
 BOOST_CLASS_EXPORT_IMPLEMENT(MovieContent)
 
 IMPLEMENT_SERIALIZE_FOR_XML(MovieContent)
@@ -67,8 +69,9 @@ bool MovieContent::readMetadata()
  _frameDuration = movie.getFrameDuration();
  return true;
  }
- catch (const std::runtime_error&)
+ catch (const std::runtime_error& e)
  {
+ put_log(LOG_DEBUG, LOG_AV, e.what());
  return false;
  }
 }

tide/wall/qml/textureUtils.cpp

@@ -1,6 +1,6 @@
 /*********************************************************************/
-/* Copyright (c) 2017, EPFL/Blue Brain Project  */
-/* Raphael Dumusc <raphael.dumusc@epfl.ch>  */
+/* Copyright (c) 2017-2018, EPFL/Blue Brain Project */
+/*  Raphael Dumusc <raphael.dumusc@epfl.ch> */
 /* All rights reserved. */
 /* */
 /* Redistribution and use in source and binary forms, with or */
@@ -63,17 +63,23 @@ void upload(const Image& image, const uint srcTextureIdx, QOpenGLBuffer& pbo)
  pbo.release();
 }
 
+GLint _getUnpackAlignment(const uint textureWidth)
+{
+ if (textureWidth % 4 == 0)
+ return 4;
+ if (textureWidth % 2 == 0)
+ return 2;
+ return 1;
+}
+
 void copy(QOpenGLBuffer& pbo, QSGTexture& texture, const uint glTexFormat)
 {
  auto gl = QOpenGLContext::currentContext()->functions();
+
  const auto textureSize = texture.textureSize();
 
- GLint alignment = 1;
- if ((textureSize.width() % 4) == 0)
- alignment = 4;
- else if ((textureSize.width() % 2) == 0)
- alignment = 2;
- gl->glPixelStorei(GL_UNPACK_ALIGNMENT, alignment);
+ gl->glPixelStorei(GL_UNPACK_ALIGNMENT,
+ _getUnpackAlignment(textureSize.width()));
 
  texture.bind();
  pbo.bind();
@@ -86,8 +92,9 @@ void copy(QOpenGLBuffer& pbo, QSGTexture& texture, const uint glTexFormat)
 std::unique_ptr<QSGTexture> createTexture(const QSize& size,
  QQuickWindow& window)
 {
- uint textureID = 0;
  auto gl = QOpenGLContext::currentContext()->functions();
+
+ auto textureID = GLuint{0};
  gl->glGenTextures(1, &textureID);
  gl->glBindTexture(GL_TEXTURE_2D, textureID);
  gl->glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, size.width(), size.height(), 0,
@@ -102,17 +109,18 @@ std::unique_ptr<QSGTexture> createTexture(const QSize& size,
 std::unique_ptr<QSGTexture> createTextureRgba(const QSize& size,
  QQuickWindow& window)
 {
- uint textureID;
  auto gl = QOpenGLContext::currentContext()->functions();
- gl->glActiveTexture(GL_TEXTURE0);
+
+ auto textureID = GLuint{0};
  gl->glGenTextures(1, &textureID);
  gl->glBindTexture(GL_TEXTURE_2D, textureID);
  gl->glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, size.width(), size.height(), 0,
  GL_RGBA, GL_UNSIGNED_BYTE, 0);
  gl->glBindTexture(GL_TEXTURE_2D, 0);
 
- const auto textureFlags =
- QQuickWindow::CreateTextureOptions(QQuickWindow::TextureOwnsGLTexture);
+ const auto textureFlags = QQuickWindow::CreateTextureOptions(
+ QQuickWindow::TextureOwnsGLTexture |
+ QQuickWindow::TextureHasAlphaChannel);
  return std::unique_ptr<QSGTexture>{
  window.createTextureFromId(textureID, size, textureFlags)};
 }