From 5a079a2d114f96d4847d1ee305d5b7c16eeec50e Mon Sep 17 00:00:00 2001 From: 3gg <3gg@shellblade.net> Date: Sat, 27 Dec 2025 12:03:39 -0800 Subject: Initial commit --- .../src/video/kmsdrm/SDL_kmsdrmopengles.c | 203 +++++++++++++++++++++ 1 file changed, 203 insertions(+) create mode 100644 contrib/SDL-3.2.8/src/video/kmsdrm/SDL_kmsdrmopengles.c (limited to 'contrib/SDL-3.2.8/src/video/kmsdrm/SDL_kmsdrmopengles.c') diff --git a/contrib/SDL-3.2.8/src/video/kmsdrm/SDL_kmsdrmopengles.c b/contrib/SDL-3.2.8/src/video/kmsdrm/SDL_kmsdrmopengles.c new file mode 100644 index 0000000..cc93cde --- /dev/null +++ b/contrib/SDL-3.2.8/src/video/kmsdrm/SDL_kmsdrmopengles.c @@ -0,0 +1,203 @@ +/* + Simple DirectMedia Layer + Copyright (C) 1997-2025 Sam Lantinga + + This software is provided 'as-is', without any express or implied + warranty. In no event will the authors be held liable for any damages + arising from the use of this software. + + Permission is granted to anyone to use this software for any purpose, + including commercial applications, and to alter it and redistribute it + freely, subject to the following restrictions: + + 1. The origin of this software must not be misrepresented; you must not + claim that you wrote the original software. If you use this software + in a product, an acknowledgment in the product documentation would be + appreciated but is not required. + 2. Altered source versions must be plainly marked as such, and must not be + misrepresented as being the original software. + 3. This notice may not be removed or altered from any source distribution. +*/ + +#include "SDL_internal.h" + +#ifdef SDL_VIDEO_DRIVER_KMSDRM + +#include "SDL_kmsdrmvideo.h" +#include "SDL_kmsdrmopengles.h" +#include "SDL_kmsdrmdyn.h" +#include + +#ifndef EGL_PLATFORM_GBM_MESA +#define EGL_PLATFORM_GBM_MESA 0x31D7 +#endif + +// EGL implementation of SDL OpenGL support + +void KMSDRM_GLES_DefaultProfileConfig(SDL_VideoDevice *_this, int *mask, int *major, int *minor) +{ + /* if SDL was _also_ built with the Raspberry Pi driver (so we're + definitely a Pi device) or with the ROCKCHIP video driver + (it's a ROCKCHIP device), default to GLES2. */ +#if defined(SDL_VIDEO_DRIVER_RPI) || defined(SDL_VIDEO_DRIVER_ROCKCHIP) + *mask = SDL_GL_CONTEXT_PROFILE_ES; + *major = 2; + *minor = 0; +#endif +} + +bool KMSDRM_GLES_LoadLibrary(SDL_VideoDevice *_this, const char *path) +{ + /* Just pretend you do this here, but don't do it until KMSDRM_CreateWindow(), + where we do the same library load we would normally do here. + because this gets called by SDL_CreateWindow() before KMSDR_CreateWindow(), + so gbm dev isn't yet created when this is called, AND we can't alter the + call order in SDL_CreateWindow(). */ +#if 0 + NativeDisplayType display = (NativeDisplayType)_this->internal->gbm_dev; + return SDL_EGL_LoadLibrary(_this, path, display, EGL_PLATFORM_GBM_MESA); +#endif + return true; +} + +void KMSDRM_GLES_UnloadLibrary(SDL_VideoDevice *_this) +{ + /* As with KMSDRM_GLES_LoadLibrary(), we define our own "dummy" unloading function + so we manually unload the library whenever we want. */ +} + +SDL_EGL_CreateContext_impl(KMSDRM) + +bool KMSDRM_GLES_SetSwapInterval(SDL_VideoDevice *_this, int interval) +{ + if (!_this->egl_data) { + return SDL_SetError("EGL not initialized"); + } + + if (interval == 0 || interval == 1) { + _this->egl_data->egl_swapinterval = interval; + } else { + return SDL_SetError("Only swap intervals of 0 or 1 are supported"); + } + + return true; +} + +bool KMSDRM_GLES_SwapWindow(SDL_VideoDevice *_this, SDL_Window *window) +{ + SDL_WindowData *windata = window->internal; + SDL_DisplayData *dispdata = SDL_GetDisplayDriverDataForWindow(window); + SDL_VideoData *viddata = _this->internal; + KMSDRM_FBInfo *fb_info; + int ret = 0; + + /* Always wait for the previous issued flip before issuing a new one, + even if you do async flips. */ + uint32_t flip_flags = DRM_MODE_PAGE_FLIP_EVENT; + + // Skip the swap if we've switched away to another VT + if (windata->egl_surface == EGL_NO_SURFACE) { + // Wait a bit, throttling to ~100 FPS + SDL_Delay(10); + return true; + } + + // Recreate the GBM / EGL surfaces if the display mode has changed + if (windata->egl_surface_dirty) { + KMSDRM_CreateSurfaces(_this, window); + } + + /* Wait for confirmation that the next front buffer has been flipped, at which + point the previous front buffer can be released */ + if (!KMSDRM_WaitPageflip(_this, windata)) { + return SDL_SetError("Wait for previous pageflip failed"); + } + + // Release the previous front buffer + if (windata->bo) { + KMSDRM_gbm_surface_release_buffer(windata->gs, windata->bo); + windata->bo = NULL; + } + + windata->bo = windata->next_bo; + + /* Mark a buffer to become the next front buffer. + This won't happen until pagelip completes. */ + if (!(_this->egl_data->eglSwapBuffers(_this->egl_data->egl_display, + windata->egl_surface))) { + return SDL_SetError("eglSwapBuffers failed"); + } + + /* From the GBM surface, get the next BO to become the next front buffer, + and lock it so it can't be allocated as a back buffer (to prevent EGL + from drawing into it!) */ + windata->next_bo = KMSDRM_gbm_surface_lock_front_buffer(windata->gs); + if (!windata->next_bo) { + return SDL_SetError("Could not lock front buffer on GBM surface"); + } + + // Get an actual usable fb for the next front buffer. + fb_info = KMSDRM_FBFromBO(_this, windata->next_bo); + if (!fb_info) { + return SDL_SetError("Could not get a framebuffer"); + } + + if (!windata->bo) { + /* On the first swap, immediately present the new front buffer. Before + drmModePageFlip can be used the CRTC has to be configured to use + the current connector and mode with drmModeSetCrtc */ + ret = KMSDRM_drmModeSetCrtc(viddata->drm_fd, + dispdata->crtc->crtc_id, fb_info->fb_id, 0, 0, + &dispdata->connector->connector_id, 1, &dispdata->mode); + + if (ret) { + return SDL_SetError("Could not set videomode on CRTC."); + } + } else { + /* On subsequent swaps, queue the new front buffer to be flipped during + the next vertical blank + + Remember: drmModePageFlip() never blocks, it just issues the flip, + which will be done during the next vblank, or immediately if + we pass the DRM_MODE_PAGE_FLIP_ASYNC flag. + Since calling drmModePageFlip() will return EBUSY if we call it + without having completed the last issued flip, we must pass the + DRM_MODE_PAGE_FLIP_ASYNC if we don't block on EGL (egl_swapinterval = 0). + That makes it flip immediately, without waiting for the next vblank + to do so, so even if we don't block on EGL, the flip will have completed + when we get here again. */ + if (_this->egl_data->egl_swapinterval == 0 && viddata->async_pageflip_support) { + flip_flags |= DRM_MODE_PAGE_FLIP_ASYNC; + } + + ret = KMSDRM_drmModePageFlip(viddata->drm_fd, dispdata->crtc->crtc_id, + fb_info->fb_id, flip_flags, &windata->waiting_for_flip); + + if (ret == 0) { + windata->waiting_for_flip = true; + } else { + SDL_LogError(SDL_LOG_CATEGORY_VIDEO, "Could not queue pageflip: %d", ret); + } + + /* Wait immediately for vsync (as if we only had two buffers). + Even if we are already doing a WaitPageflip at the beginning of this + function, this is NOT redundant because here we wait immediately + after submitting the image to the screen, reducing lag, and if + we have waited here, there won't be a pending pageflip so the + WaitPageflip at the beginning of this function will be a no-op. + Just leave it here and don't worry. + Run your SDL program with "SDL_VIDEO_DOUBLE_BUFFER=1 " + to enable this. */ + if (windata->double_buffer) { + if (!KMSDRM_WaitPageflip(_this, windata)) { + return SDL_SetError("Immediate wait for previous pageflip failed"); + } + } + } + + return true; +} + +SDL_EGL_MakeCurrent_impl(KMSDRM) + +#endif // SDL_VIDEO_DRIVER_KMSDRM -- cgit v1.2.3