The OpenGL ES 2.0 thread

	Bottom Previous Topic Next Topic
Register To Post

« 1 ... 6 7 8 (9)

Capehill

Re: The OpenGL ES 2.0 thread

Posted on: 2025/2/2 8:22 #161

Just can't stay away

@elfpipe

What kind of problems? Is there some GL error or anything if you run glSnoop?

elfpipe

Re: The OpenGL ES 2.0 thread

Posted on: 2025/2/2 12:03 #162

Just can't stay away

@Capehill

glCompileShader returns a GL_COMPILE_STATUS of 0, when the call is made in the new thread. glGetShaderInfoLog in this case returns nothing.

glSnoop does an enormous amount of logging. It also interestingly removes the compile error. I get this in the log:

Quote:

[262.857543] Shell Process 'threadedqopenglwidget': W3DN_DrawArrays: <- Result 22 (W3DNEC_NOSHADERPIPELINE)
[262.866984] Shell Process 'threadedqopenglwidget': Warning: unsuccessful operation detected
[262.875127] Shell Process 'threadedqopenglwidget': GL error 1286 (GL_INVALID_FRAMEBUFFER_OPERATION) detected after DrawArrays

EDIT: It could be an issue with context sharing. Maybe I have some wiggle room. EDIT: Probably not, though.

Edited by elfpipe on 2025/2/2 12:27:57
Edited by elfpipe on 2025/2/2 14:05:08
Edited by elfpipe on 2025/2/3 8:53:37

kas1e

Re: The OpenGL ES 2.0 thread

Posted on: 7/6 16:10 #163

Home away from home

@All
Do not know if it worth to report anymore, due to all known "dunno if anything will be released" , but seems i found another bug in ogles2 (at least i think so): glBindTexture(GL_TEXTURE_2D, 0) leak memory for no reasson and on exit not free it as well.

That call should just unbind the currently bound 2D texture and restore texture unit 0’s binding to the GLES default object. It should not allocate anything per call. And on x86/etc that it. But seems on our ogles2 realisation this eat memory a lot with no reasson.

I.e:

- Binding real texture IDs does not leak.
- Cycling between real texture IDs does not leak.
- glActiveTexture(GL_TEXTURE0) alone does not leak.
- glBindTexture(GL_TEXTURE_2D, 0) leaks heavily.

It looks like OGLES2 internal bug is: when texture ID 0 is bound, the library creates or realizes some internal “default/no texture” Nova-side object/state each time,
but does not reuse or free it. Or it triggers a state/submit path that appends retained objects for texture 0.

There is SDL2 based test case if anyone need it:


#include <SDL.h>

#include <SDL_opengles2.h>



#include <stdio.h>



static GLuint create_texture(void)

{

    static const unsigned char pixel[4] = {255U, 255U, 255U, 255U};

    GLuint texture;



    texture = 0U;

    glGenTextures(1, &texture);

    glBindTexture(GL_TEXTURE_2D, texture);

    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 1, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixel);

    return texture;

}



int main(int argc, char **argv)

{

    SDL_Window *window;

    SDL_GLContext context;

    GLuint texture;

    unsigned int start_ms;

    unsigned int last_ms;

    unsigned long frames;

    unsigned long binds;



    (void)argc;

    (void)argv;



    if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER) != 0) {

        return 1;

    }



    (void)SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);

    (void)SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);

    (void)SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);

    (void)SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);



    window = SDL_CreateWindow(

        "glBindTexture 0 leak",

        SDL_WINDOWPOS_CENTERED,

        SDL_WINDOWPOS_CENTERED,

        320,

        240,

        SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN);

    if (window == NULL) {

        SDL_Quit();

        return 1;

    }



    context = SDL_GL_CreateContext(window);

    if (context == NULL) {

        SDL_DestroyWindow(window);

        SDL_Quit();

        return 1;

    }



    if (SDL_GL_MakeCurrent(window, context) != 0) {

        SDL_GL_DeleteContext(context);

        SDL_DestroyWindow(window);

        SDL_Quit();

        return 1;

    }



    texture = create_texture();

    if (texture == 0U || glGetError() != GL_NO_ERROR) {

        SDL_GL_DeleteContext(context);

        SDL_DestroyWindow(window);

        SDL_Quit();

        return 1;

    }



    frames = 0UL;

    binds = 0UL;

    start_ms = SDL_GetTicks();

    last_ms = start_ms;



    for (;;) {

        SDL_Event event;

        unsigned int now_ms;

        int i;



        while (SDL_PollEvent(&event)) {

            if (event.type == SDL_QUIT ||

                (event.type == SDL_KEYDOWN && event.key.keysym.sym == SDLK_ESCAPE)) {

                goto done;

            }

        }



        for (i = 0; i < 64; ++i) {

            glBindTexture(GL_TEXTURE_2D, 0);

            ++binds;

        }



        SDL_GL_SwapWindow(window);

        SDL_Delay(1);

        ++frames;



        now_ms = SDL_GetTicks();

        if (now_ms - last_ms >= 1000U) {

            printf("t=%u frames=%lu binds=%lu\n", (now_ms - start_ms) / 1000U, frames, binds);

            fflush(stdout);

            last_ms = now_ms;

        }

        if (now_ms - start_ms >= 20000U) {

            break;

        }

    }



done:

    glDeleteTextures(1, &texture);

    (void)SDL_GL_MakeCurrent(window, NULL);

    SDL_GL_DeleteContext(context);

    SDL_DestroyWindow(window);

    SDL_Quit();

    return 0;

}

It can be build for x86 too if need it (and there it will have no issues, of course).

Edited by kas1e on 2026/7/6 16:25:37
Edited by kas1e on 2026/7/6 16:31:37

Join us to improve dopus5!
AmigaOS4 on youtube

afxgroup

Re: The OpenGL ES 2.0 thread

Posted on: 7/7 9:34 #164

Amigans Defender

I think I've found the same issue but I don't think it will be never fixed anymore..

i'm really tired...

Capehill

Re: The OpenGL ES 2.0 thread

Posted on: 7/7 10:49 #165

Just can't stay away

@kas1e

glBindTexture(GL_TEXTURE_2D, 0) creates a new texture sampler each time and sets its parameters. So yes, it looks like a bug.

Maijestro

Re: The OpenGL ES 2.0 thread

Posted on: 7/11 13:38 #166

Just can't stay away

Hi @kas1e, @Capehill,

just had to post this - I spent basically all day today chasing a memory leak in my Unreal (1998) AmigaOS4 port and this thread is the reason I finally cracked it. Thank you both.

Quick version: RAM kept draining while playing, even standing completely still, worst in scenes with animated textures. Ruled out literally everything in my own code before finding this thread - sound, render options, pixel format, you name it, none of it made a difference.

Then I saw kas1e's post about glBindTexture(GL_TEXTURE_2D, 0) and went "...wait." Checked my code, and yep - I was calling exactly that, via a ResetTexture() helper, once per visible surface, up to 3 times each. In a normal scene that's easily hundreds of calls a frame. Explains everything.

Swapped it for binding a dummy 1x1 texture instead of 0, and the leak is just... gone. Tested standing still for 10 minutes, memory didn't budge.

So yeah - this is 100% a real bug that bites real applications, not just a synthetic test case. Really glad you found and reported it, would've been banging my head against this for a lot longer otherwise. Cheers!

MacStudio ARM M1 Max Qemu//Pegasos2 AmigaOs4.1 FE / AmigaOne x5000/40 AmigaOs4.1 FE

Register To Post	« 1 ... 6 7 8 (9)
	Top Previous Topic Next Topic

Currently Active Users Viewing This Thread: 1 ( 0 members and 1 Anonymous Users )