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Messages - MichaelJPCT

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Support / Re: about the strength of specular light
« on: February 13, 2019, 02:21:02 pm »
i think of Config.specPow , can specPow be variable at runtime ?

Support / Re: gpu bug ?
« on: January 19, 2019, 05:29:43 pm »
there is no problem on mali gpu , so should be the problem of powervr gpu

Support / Re: gpu bug ?
« on: January 19, 2019, 09:51:09 am »
i tried disabling depth write before drawing the shadows(the mesh holding the texture) , the result is better - from most angles they are correct, still from some angles , wrong.
without that fix , from most angles shadows are wrong.

Support / Re: gpu bug ?
« on: January 15, 2019, 05:08:09 pm »
i suspect that when a transparent object is rendered, depth buffer writing is enabled with powervr gpu, which shouldn't be done.

Support / is there such a thing as single channel texture in vram?
« on: January 12, 2019, 07:57:21 am »
i think all textures have 3 or 4 color channels. but sometimes a texture has no color , only greyscale info is needed.
if the texture in vram is stored as single channel, then it occupies 1/4 of memory. isn't it great?

another question, can RTT texture be ETC compressed in vram?

Support / Re: gpu bug ?
« on: January 11, 2019, 01:51:12 pm »
i roughly calculate the size of squares, it is most likely 32.

Support / Re: gpu bug ?
« on: January 11, 2019, 01:42:42 pm »
i don't know the size of the flickering squares, but might be 32. the width of screen is 1920. the squares are axis-aligned to  screen.
but the patterns of flicker are multiple, sometimes i see narrow bands. pattern changes with camera position and angle, not by time.
i tried setting usePowerVRTweaks to false, and the whole device hanged. i had to turn off power to reset it.

Support / Re: gpu bug ?
« on: January 11, 2019, 12:59:43 pm »
i don't have a way to take screenshots on that device yet, so i use real camera to shoot the imgs.
2 shadows are overlapping in these screenshots(the meshes holding the texture is much larger than the dark area of  shadow).
shadows are at exact same height.
the shadow closer to camera flickers(always true).

Support / gpu bug ?
« on: January 11, 2019, 04:36:14 am »
my project sometimes has 2 transparent objects(shadows) overlapping but at the same height.
on Powervr 6250 gpu , the objects flicker, like the behavior of Z-fighting. on maliT720, it doesn't happen.
it shouldn't happen because they are transparent, they should co-exist.
what might be the cause of Z-fighting and can it be fixed?

Projects / Re: my project - Vehicle Simulation
« on: January 04, 2019, 03:53:54 pm »
at early stage there are only aircrafts, but if i have enough time , it can have other vehicles, mainly wheeled vehicles (cars).
also human(like fps game) , weapons(bullets , missiles) etc.
the focus is on physics simulation.

Projects / Re: my project - Vehicle Simulation
« on: December 28, 2018, 06:33:56 pm »
more imgs can be found on

Projects / my project - Vehicle Simulation
« on: December 28, 2018, 06:28:35 pm »
this project uses JPCT-AE.
so far i can only post screenshots.

Support / Re: about the strength of specular light
« on: November 12, 2018, 12:16:35 pm »
i see. the built-in shaders are complex enough already. thanks.

Support / about the strength of specular light
« on: November 11, 2018, 07:00:01 pm »
Hi Egon,
i found the reflected light color is related to texture color - the light on white object is whiter than that on dark color  objects.
but in reality, some dark colored object can reflect very bright light, such as dark colored glass.
i don't aim for complex graphics so that's not very important by now.
in some engines, there is concept of " material " - not just texture, but how strong do ambient light, diffuse light, specular light affect an object.
would you consider having this in JPCT? or people need to write new shaders if necessary.

Support / Re: about Light Discard Distance
« on: November 06, 2018, 12:29:28 pm »
that makes sense , thanks.

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