Implement glScissor support

PabloPL commented 6 years ago

It's mostly done on https://github.com/yuq/mesa-lima/pull/10. There is only one case to handle - when scissors = (0,0,0,0)

Limadriver in this case is not doing any scissors and displaying full/normal image (probably a bug)

Mali binary driver is generating only following plbu commands (dump from egl_quad_flat from limadrver tests)

0x00000200 0x1000010b // PRIMITIVE_SETUP
0x00010000 0x1000010c // BLOCK_STEP
0x1d001d00 0x10000109 // TILED_DIMENSIONS
0x0000001e 0x30000000 // BLOCK_STRIDE
0x400f8400 0x280001c1 // ARRAY_ADDRESS
0x00000000 0x10000107 // VIEWPORT_X
0x43f00000 0x10000108 // VIEWPORT_W
0x00000000 0x10000105 // VIEWPORT_Y
0x43f00000 0x10000106 // VIEWPORT_H
0x40040000 0x10000103 // TILE_HEAP_START
0x40070000 0x10000104 // TILE_HEAP_END
0x00000000 0x50000000 // END

PabloPL commented 6 years ago

And this is what is generated by mesa currently

lima: dump command stream enabled
num config 1
gbm format 34325241
lima: update attribute info at va 43800
0000: 0x0008c000 0x00012002 0x0008c00c 0x00012003
lima: update varying info at va 43000
0000: 0x00041000 0x00008020 0x00040000 0x00008003
lima add vs cmd at va 45000
0000: 0x00028000 0x50000000 0x00000001 0x50000000
0010: 0x00044000 0x30000000 0x00042000 0x40020000
0020: 0x00100400 0x10000040 0x01000100 0x10000042
0030: 0x00000003 0x10000041 0x00043800 0x20040000
0040: 0x00043000 0x20040008 0x04000000 0x00000000
0050: 0x00000000 0x60000000 0x00000000 0x50000000
lima add plbu cmd at va 45800
0000: 0x00000200 0x1000010b 0x00000000 0x1000010c
0010: 0x0f000f00 0x10000109 0x00000010 0x30000000
0020: 0x00042800 0x280000ff 0x00000000 0x10000107
0030: 0x43800000 0x10000108 0x00000000 0x10000105
0040: 0x43800000 0x10000106 0x00010002 0x60000000
0050: 0x00002200 0x1000010b 0x000498c0 0x80004100
0060: 0x00000000 0x1000010a 0x00000000 0x1000010e
0070: 0x3f800000 0x1000010f 0x04000000 0x00060000
0080: 0x00010001 0x60000000 0x00000000 0x00000000
lima: add render state at va 498c0
0000: 0x00000000 0x00000000 0xfc3b1ad2 0x0000003e
0010: 0xffff0000 0xff000007 0xff000007 0x00000000
0020: 0x0000f807 0x00048003 0x00000000 0x00000000
0030: 0x00000000 0x00000302 0x00003000 0x00040000
0
lima: update attribute info at va 43840
0000: 0x0008c090 0x00006002 0x0008c0b4 0x00008003
lima: update varying info at va 43040
0000: 0x00041040 0x00008020 0x00040040 0x00008003
lima add vs cmd at va 45060
0000: 0x00028000 0x50000000 0x00000001 0x50000000
0010: 0x00044000 0x30030000 0x00042040 0x40050000
0020: 0x00301000 0x10000040 0x01000100 0x10000042
0030: 0x00000003 0x10000041 0x00043840 0x20040000
0040: 0x00043040 0x20040008 0x03000000 0x00000000
0050: 0x00000000 0x60000000 0x00000000 0x50000000
lima add plbu cmd at va 45888
0000: 0x00010002 0x60000000 0x00002200 0x1000010b
0010: 0x00049900 0x80004104 0x007f8100 0xffffe000
0020: 0x00000000 0x1000010a 0x00000000 0x1000010e
0030: 0x3f800000 0x1000010f 0x03000000 0x00040000
0040: 0x00010001 0x60000000 0x00000000 0x00000000
lima: add render state at va 49900
0000: 0x00000000 0x00000000 0xfc3b1ad2 0x0000003e
0010: 0xffff0000 0xff000007 0xff000007 0x00000000
0020: 0x0000f807 0x00048043 0x00000000 0x00000000
0030: 0x00000000 0x00000302 0x00003000 0x00040040
gp submit wait error
lima varying dump at va 40000
0000: 0.000000 0.000000 0.000000 0.000000
0010: 0.000000 0.000000 0.000000 0.000000
0020: 0.000000 0.000000 0.000000 0.000000
0030: 0.000000 0.000000 0.000000 0.000000
0040: 0.000000 0.000000 0.000000 0.000000
0050: 0.000000 0.000000 0.000000 0.000000
0060: 0.000000 0.000000 0.000000 0.000000
0070: 0.000000 0.000000 0.000000 0.000000
0080: 0.000000 0.000000 0.000000 0.000000
0090: 0.000000 0.000000 0.000000 0.000000
00a0: 0.000000 0.000000 0.000000 0.000000
00b0: 0.000000 0.000000 0.000000 0.000000
00c0: 0.000000 0.000000 0.000000 0.000000
00d0: 0.000000 0.000000 0.000000 0.000000
00e0: 0.000000 0.000000 0.000000 0.000000
00f0: 0.000000 0.000000 0.000000 0.000000
lima gl_pos dump at va 41000
0000: -1.000000 -1.000000 1.000000 1.000000
0010: -1.000000 -1.000000 1.000000 1.000000
0020: -1.000000 -1.000000 1.000000 1.000000
0030: -1.000000 -1.000000 1.000000 1.000000
0040: 0.000000 0.000000 0.000000 0.000000
0050: 0.000000 0.000000 0.000000 0.000000
0060: 0.000000 0.000000 0.000000 0.000000
0070: 0.000000 0.000000 0.000000 0.000000
0080: 0.000000 0.000000 0.000000 0.000000
0090: 0.000000 0.000000 0.000000 0.000000
00a0: 0.000000 0.000000 0.000000 0.000000
00b0: 0.000000 0.000000 0.000000 0.000000
00c0: 0.000000 0.000000 0.000000 0.000000
00d0: 0.000000 0.000000 0.000000 0.000000
00e0: 0.000000 0.000000 0.000000 0.000000
00f0: 0.000000 0.000000 0.000000 0.000000
gbm-surface: main.c:289: Render: Assertion `glGetError() == GL_NO_ERROR' failed.
Aborted

@yuq Any ideas how to fix this? I've tried to skip adding plbu cmd if scissor is zero, but it didn't worked (it was generating second plbu cmd list empty).

yuq commented 6 years ago

PLBU cmd is necessary for every frame. You may try to generate binary mali driver like PLBU cmd when scissor is 0.

PabloPL commented 6 years ago

I've already done this and posted in first comment (with some comments).

yuq commented 6 years ago

BTW. do we need to do anything if scissor is 0?

PabloPL commented 6 years ago

I think we should render empty screen (since we set that we don't want anything to display).

yuq commented 6 years ago

To my understanding, if set scissor to 0, no following draw should apply to the frame buffer, including the glClear(). So this frame buffer should remain the same as last none-zero draw result. Can you make an experiment by running the scissor test on a normal desktop with AMD/NV mesa driver to see what's expected result? If we need do nothing, we may skip the draws when scissor is 0.

PabloPL commented 6 years ago

Made a test using mali binary driver - it rendered an empty screen (dumped using mali syscall tracker). Will do the same with intel in a few minutes (since this is gpu which i have on my laptop) and update comment.

Edit 1: On intel gpu i got the same screen/window (empty/filled with black color).

GL_VENDOR "Intel Open Source Technology Center" GL_RENDERER "Mesa DRI Intel(R) HD Graphics 5500 (Broadwell GT2) " GL_VERSION "OpenGL ES 3.1 Mesa 17.0.7" Ubuntu 17.04

Edit 2: Test was performed using egl_quad_flat from limare (which draws only one frame).

Edit 3: Used cube_companion_spinnin and make it display 4 frames and then at last frame apply zero scissors and looks like You're right - it's still displaying previous image (tested on mali binary driver and on intel gpu).

yuq commented 6 years ago

Then we can just skip draws when scissor=0 for now.

PabloPL commented 6 years ago

Working implementation (for both zero and non zero scissor) in https://github.com/yuq/mesa-lima/pull/15.

Then we can just skip draws when scissor=0 for now.

It turns out that we can't skip drawing. We need to

create plb cmd header (if not already created) and skipp all other plb cmds
skip creating vs cmd list Then it's working fine.

PabloPL commented 6 years ago

TODO

we should set scissor (non zero case) only for the first draw that enabled the scissor and for latter draw only if scissor is dirty
- check why scissor is not affecting bounds of region cleared by glClear

yuq / mesa-lima

Implement glScissor support #13