Correct top-down decoded video orientation in casting windows

native/cast_frame.h

@@ -21,7 +21,8 @@ struct CastFrame {
   static auto blit=(PFNGLBLITFRAMEBUFFERPROC)glXGetProcAddressARB((const GLubyte*)"glBlitFramebuffer");
   static auto del=(PFNGLDELETEFRAMEBUFFERSPROC)glXGetProcAddressARB((const GLubyte*)"glDeleteFramebuffers");
   if(!gen||!bind||!attach||!blit||!del)return target;
-  if(!composite)glGenTextures(1,&composite);glBindTexture(GL_TEXTURE_2D,composite);if(composite_width!=target_width||composite_height!=target_height){glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA8,target_width,target_height,0,GL_BGRA,GL_UNSIGNED_BYTE,nullptr);composite_width=target_width;composite_height=target_height;}GLuint fbo[2];gen(2,fbo);bind(GL_READ_FRAMEBUFFER,fbo[0]);attach(GL_READ_FRAMEBUFFER,GL_COLOR_ATTACHMENT0,GL_TEXTURE_2D,texture,0);bind(GL_DRAW_FRAMEBUFFER,fbo[1]);attach(GL_DRAW_FRAMEBUFFER,GL_COLOR_ATTACHMENT0,GL_TEXTURE_2D,composite,0);blit(0,0,width,height,0,0,target_width,target_height,GL_COLOR_BUFFER_BIT,GL_LINEAR);
+  if(!composite)glGenTextures(1,&composite);glBindTexture(GL_TEXTURE_2D,composite);if(composite_width!=target_width||composite_height!=target_height){glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA8,target_width,target_height,0,GL_BGRA,GL_UNSIGNED_BYTE,nullptr);composite_width=target_width;composite_height=target_height;}GLuint fbo[2];gen(2,fbo);bind(GL_READ_FRAMEBUFFER,fbo[0]);attach(GL_READ_FRAMEBUFFER,GL_COLOR_ATTACHMENT0,GL_TEXTURE_2D,texture,0);bind(GL_DRAW_FRAMEBUFFER,fbo[1]);attach(GL_DRAW_FRAMEBUFFER,GL_COLOR_ATTACHMENT0,GL_TEXTURE_2D,composite,0);// Decoder frames are top-down; CEF controls are already flipped for GL.
+  blit(0,height,width,0,0,0,target_width,target_height,GL_COLOR_BUFFER_BIT,GL_LINEAR);
   // CEF paints transparent, premultiplied controls over the full video plane.
   // Keep its texture intact so partial CEF damage never contains stale video.
   bind(GL_FRAMEBUFFER,fbo[1]);glPushAttrib(GL_ALL_ATTRIB_BITS);glViewport(0,0,target_width,target_height);glDisable(GL_DEPTH_TEST);glDisable(GL_SCISSOR_TEST);glEnable(GL_TEXTURE_2D);glEnable(GL_BLEND);glBlendFunc(GL_ONE,GL_ONE_MINUS_SRC_ALPHA);glColor4f(1,1,1,1);glBindTexture(GL_TEXTURE_2D,target);

tests/cast_frame.cpp

@@ -14,7 +14,14 @@ int main(){
  CastFrame frame;frame.width=frame.height=2;glGenTextures(1,&frame.texture);glBindTexture(GL_TEXTURE_2D,frame.texture);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);std::vector<uint8_t> blue(16);for(size_t n=0;n<blue.size();n+=4){blue[n+2]=255;blue[n+3]=255;}glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA8,2,2,0,GL_RGBA,GL_UNSIGNED_BYTE,blue.data());
  GLuint ui;glGenTextures(1,&ui);glBindTexture(GL_TEXTURE_2D,ui);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);std::vector<uint8_t> controls(64);for(size_t n=0;n<controls.size();n+=4){controls[n]=128;controls[n+3]=128;}glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA8,4,4,0,GL_RGBA,GL_UNSIGNED_BYTE,controls.data());
  auto output=frame.draw(ui,4,4);assert(output!=ui);glBindTexture(GL_TEXTURE_2D,output);std::vector<uint8_t> pixels(64);glGetTexImage(GL_TEXTURE_2D,0,GL_RGBA,GL_UNSIGNED_BYTE,pixels.data());for(size_t n=0;n<pixels.size();n+=4){assert(pixels[n]==128);assert(pixels[n+1]==0);assert(pixels[n+2]>=126&&pixels[n+2]<=128);assert(pixels[n+3]==255);}glBindTexture(GL_TEXTURE_2D,ui);glGetTexImage(GL_TEXTURE_2D,0,GL_RGBA,GL_UNSIGNED_BYTE,pixels.data());assert(pixels==controls);
- std::fill(controls.begin(),controls.end(),0);glTexSubImage2D(GL_TEXTURE_2D,0,0,0,4,4,GL_RGBA,GL_UNSIGNED_BYTE,controls.data());output=frame.draw(ui,4,4);glBindTexture(GL_TEXTURE_2D,output);glGetTexImage(GL_TEXTURE_2D,0,GL_RGBA,GL_UNSIGNED_BYTE,pixels.data());assert(pixels[0]==0&&pixels[2]==255);assert(glGetError()==GL_NO_ERROR);glDeleteTextures(1,&ui);
+ std::fill(controls.begin(),controls.end(),0);glTexSubImage2D(GL_TEXTURE_2D,0,0,0,4,4,GL_RGBA,GL_UNSIGNED_BYTE,controls.data());output=frame.draw(ui,4,4);glBindTexture(GL_TEXTURE_2D,output);glGetTexImage(GL_TEXTURE_2D,0,GL_RGBA,GL_UNSIGNED_BYTE,pixels.data());assert(pixels[0]==0&&pixels[2]==255);
+ // Raw decoder rows are top-down: red/green above blue/yellow.
+ // The composited GL texture must put blue/yellow on its bottom row.
+ const uint8_t corners[]={255,0,0,255, 0,255,0,255, 0,0,255,255, 255,255,0,255};
+ glBindTexture(GL_TEXTURE_2D,frame.texture);glTexSubImage2D(GL_TEXTURE_2D,0,0,0,2,2,GL_RGBA,GL_UNSIGNED_BYTE,corners);
+ output=frame.draw(ui,2,2);glBindTexture(GL_TEXTURE_2D,output);std::vector<uint8_t> upright(16);glGetTexImage(GL_TEXTURE_2D,0,GL_RGBA,GL_UNSIGNED_BYTE,upright.data());
+ const std::vector<uint8_t> expected={0,0,255,255, 255,255,0,255, 255,0,0,255, 0,255,0,255};assert(upright==expected);
+ assert(glGetError()==GL_NO_ERROR);glDeleteTextures(1,&ui);
  }
  glXMakeCurrent(display,None,nullptr);glXDestroyGLXPixmap(display,surface);XFreePixmap(display,pixmap);glXDestroyContext(display,context);XFree(visual);XCloseDisplay(display);std::cout<<"Full-frame video and transparent controls composition passed\n";
 }