Mali Graphics Debugger, how  can  i  reduce vertex number?

Hi  Chris,

i use cocos2d to render

i  just  use  cocosbuilder  to  conbine  png or jpg to  ccbi  file

then  addChild to the  scene

cocos2d will help me complete  other steps

so i do not understand  this  words  "Is all your rendering done to the window surface or do you use any FBOs"

can you  tell  me how  to use Mali graphics debugger  to  find FBOS  or  other  useful  data?

Forgive my poor English  o(∩_∩)o

i  found  the   edge of framebuffers  is unusual， not full  of  the  screen

can  you  tell  me  what  happen  with  my  app?

and  vertex  position  is a negative number

thanks,

Zhong

Hi  Chris,

i use cocos2d to render

i  just  use  cocosbuilder  to  conbine  png or jpg to  ccbi  file

then  addChild to the  scene

cocos2d will help me complete  other steps

so i do not understand  this  words  "Is all your rendering done to the window surface or do you use any FBOs"

can you  tell  me how  to use Mali graphics debugger  to  find FBOS  or  other  useful  data?

Forgive my poor English  o(∩_∩)o

i  found  the   edge of framebuffers  is unusual， not full  of  the  screen

can  you  tell  me  what  happen  with  my  app?

and  vertex  position  is a negative number

thanks,

Zhong

Hi zhong,

For the vertex positions, If you take a look at the shader which is transforming those positions, they will likely end up being valid screen space coordinates post transformation input values can be completely arbitrary, it's the output of the shader that counts.

As for the FBO's, if you can only see one FBO in MGD, FB0, then you are only rendering to one. You can confirm this in either the "Framebuffers" view or the "Assets" view.

As for the garbage at the side of the screen, is this visible in the final image on the device? Are you calling glClear(GL_COLOR_BUFFER_BIT) at the start of the frame? Is the viewport/scissor region set to the full size of the window when you do this? You can step through the draw calls in a captured frame with MGD and see which draw call introduces the garbage data. If it's there in the very first draw call then it's either being drawn by that draw call or you are not clearing the full buffer at the start of the frame.

As you're using Cocos2D, it's likely the above is actually abstracted below the level at which you are working. Can you let me know if there are any performance issues with your game that prompted this investigation, or are you just taking a look out of interest?

Thanks,

Chris

Hi  Chris，

For the vertex positions and the garbage at the side of the screen，i  found  the  reason ，i use samsung i9300  which resolution is 720×1280 ， but viewport of  my game is (-66,0,853,1280) ，i think the correct  viewport is (0,0,720,1280)

Thanks a lot

Hi zhong,

Glad that was the correct issue, an easy fix. Are there any other issues you'd like help with?

Thanks,

Chris