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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 20:38:23 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 20:38:23 +0000
commitff6e3c025658a5fa1affd094f220b623e7e1b24b (patch)
tree9faab72d69c92d24e349d184f5869b9796f17e0c /src/opengl/gpu.c
parentInitial commit. (diff)
downloadlibplacebo-ff6e3c025658a5fa1affd094f220b623e7e1b24b.tar.xz
libplacebo-ff6e3c025658a5fa1affd094f220b623e7e1b24b.zip
Adding upstream version 6.338.2.upstream/6.338.2upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/opengl/gpu.c')
-rw-r--r--src/opengl/gpu.c645
1 files changed, 645 insertions, 0 deletions
diff --git a/src/opengl/gpu.c b/src/opengl/gpu.c
new file mode 100644
index 0000000..b711ac5
--- /dev/null
+++ b/src/opengl/gpu.c
@@ -0,0 +1,645 @@
+/*
+ * This file is part of libplacebo.
+ *
+ * libplacebo is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * libplacebo is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with libplacebo. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "gpu.h"
+#include "common.h"
+#include "formats.h"
+#include "utils.h"
+
+#ifdef PL_HAVE_UNIX
+#include <unistd.h>
+#endif
+
+#ifdef PL_HAVE_WIN32
+#include <windows.h>
+#include <sysinfoapi.h>
+#endif
+
+static const struct pl_gpu_fns pl_fns_gl;
+
+static void gl_gpu_destroy(pl_gpu gpu)
+{
+ struct pl_gl *p = PL_PRIV(gpu);
+
+ pl_gpu_finish(gpu);
+ while (p->callbacks.num > 0)
+ gl_poll_callbacks(gpu);
+
+ pl_free((void *) gpu);
+}
+
+pl_opengl pl_opengl_get(pl_gpu gpu)
+{
+ const struct pl_gpu_fns *impl = PL_PRIV(gpu);
+ if (impl->destroy == gl_gpu_destroy) {
+ struct pl_gl *p = (struct pl_gl *) impl;
+ return p->gl;
+ }
+
+ return NULL;
+}
+
+static pl_handle_caps tex_handle_caps(pl_gpu gpu, bool import)
+{
+ pl_handle_caps caps = 0;
+ struct pl_gl *p = PL_PRIV(gpu);
+
+ if (!p->egl_dpy || (!p->has_egl_storage && !p->has_egl_import))
+ return 0;
+
+ if (import) {
+ if (pl_opengl_has_ext(p->gl, "EGL_EXT_image_dma_buf_import"))
+ caps |= PL_HANDLE_DMA_BUF;
+ } else if (!import && p->egl_ctx) {
+ if (pl_opengl_has_ext(p->gl, "EGL_MESA_image_dma_buf_export"))
+ caps |= PL_HANDLE_DMA_BUF;
+ }
+
+ return caps;
+}
+
+static inline size_t get_page_size(void)
+{
+
+#ifdef PL_HAVE_UNIX
+ return sysconf(_SC_PAGESIZE);
+#endif
+
+#ifdef PL_HAVE_WIN32
+ SYSTEM_INFO sysInfo;
+ GetSystemInfo(&sysInfo);
+ return sysInfo.dwAllocationGranularity;
+#endif
+
+ pl_assert(!"Unsupported platform!");
+}
+
+#define get(pname, field) \
+ do { \
+ GLint tmp = 0; \
+ gl->GetIntegerv((pname), &tmp); \
+ *(field) = tmp; \
+ } while (0)
+
+#define geti(pname, i, field) \
+ do { \
+ GLint tmp = 0; \
+ gl->GetIntegeri_v((pname), i, &tmp);\
+ *(field) = tmp; \
+ } while (0)
+
+pl_gpu pl_gpu_create_gl(pl_log log, pl_opengl pl_gl, const struct pl_opengl_params *params)
+{
+ struct pl_gpu_t *gpu = pl_zalloc_obj(NULL, gpu, struct pl_gl);
+ gpu->log = log;
+
+ struct pl_gl *p = PL_PRIV(gpu);
+ p->impl = pl_fns_gl;
+ p->gl = pl_gl;
+
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ struct pl_glsl_version *glsl = &gpu->glsl;
+ glsl->gles = gl_is_gles(pl_gl);
+ int ver = pl_gl->major * 10 + pl_gl->minor;
+ p->gl_ver = glsl->gles ? 0 : ver;
+ p->gles_ver = glsl->gles ? ver : 0;
+
+ // If possible, query the GLSL version from the implementation
+ const char *glslver = (char *) gl->GetString(GL_SHADING_LANGUAGE_VERSION);
+ if (glslver) {
+ PL_INFO(gpu, " GL_SHADING_LANGUAGE_VERSION: %s", glslver);
+ int major = 0, minor = 0;
+ if (sscanf(glslver, "%d.%d", &major, &minor) == 2)
+ glsl->version = major * 100 + minor;
+ }
+
+ if (!glsl->version) {
+ // Otherwise, use the fixed magic versions 100 and 300 for GLES.
+ if (p->gles_ver >= 30) {
+ glsl->version = 300;
+ } else if (p->gles_ver >= 20) {
+ glsl->version = 100;
+ } else {
+ goto error;
+ }
+ }
+
+ static const int glsl_ver_req = 130;
+ if (glsl->version < glsl_ver_req) {
+ PL_FATAL(gpu, "GLSL version too old (%d < %d), please use a newer "
+ "OpenGL implementation or downgrade libplacebo!",
+ glsl->version, glsl_ver_req);
+ goto error;
+ }
+
+ if (params->max_glsl_version && params->max_glsl_version >= glsl_ver_req) {
+ glsl->version = PL_MIN(glsl->version, params->max_glsl_version);
+ PL_INFO(gpu, "Restricting GLSL version to %d... new version is %d",
+ params->max_glsl_version, glsl->version);
+ }
+
+ if (gl_test_ext(gpu, "GL_ARB_compute_shader", 43, 0) && glsl->version >= 420) {
+ glsl->compute = true;
+ get(GL_MAX_COMPUTE_SHARED_MEMORY_SIZE, &glsl->max_shmem_size);
+ get(GL_MAX_COMPUTE_WORK_GROUP_INVOCATIONS, &glsl->max_group_threads);
+ for (int i = 0; i < 3; i++)
+ geti(GL_MAX_COMPUTE_WORK_GROUP_SIZE, i, &glsl->max_group_size[i]);
+ }
+
+ if (gl_test_ext(gpu, "GL_ARB_texture_gather", 40, 0)) {
+ get(GL_MAX_PROGRAM_TEXTURE_GATHER_COMPONENTS_ARB, &p->gather_comps);
+ get(GL_MIN_PROGRAM_TEXTURE_GATHER_OFFSET_ARB, &glsl->min_gather_offset);
+ get(GL_MAX_PROGRAM_TEXTURE_GATHER_OFFSET_ARB, &glsl->max_gather_offset);
+ }
+
+ // Query all device limits
+ struct pl_gpu_limits *limits = &gpu->limits;
+ limits->thread_safe = params->make_current;
+ limits->callbacks = gl_test_ext(gpu, "GL_ARB_sync", 32, 30);
+ limits->align_vertex_stride = 1;
+ if (gl_test_ext(gpu, "GL_ARB_pixel_buffer_object", 31, 0)) {
+ limits->max_buf_size = SIZE_MAX; // no restriction imposed by GL
+ if (gl_test_ext(gpu, "GL_ARB_uniform_buffer_object", 31, 0))
+ get(GL_MAX_UNIFORM_BLOCK_SIZE, &limits->max_ubo_size);
+ if (gl_test_ext(gpu, "GL_ARB_shader_storage_buffer_object", 43, 0) &&
+ gpu->glsl.version >= 140)
+ {
+ get(GL_MAX_SHADER_STORAGE_BLOCK_SIZE, &limits->max_ssbo_size);
+ }
+ limits->max_vbo_size = limits->max_buf_size; // No additional restrictions
+ if (gl_test_ext(gpu, "GL_ARB_buffer_storage", 44, 0)) {
+ const char *vendor = (char *) gl->GetString(GL_VENDOR);
+ limits->max_mapped_size = limits->max_buf_size;
+ limits->host_cached = strcmp(vendor, "AMD") == 0 ||
+ strcmp(vendor, "NVIDIA Corporation") == 0;
+ }
+ }
+
+ get(GL_MAX_TEXTURE_SIZE, &limits->max_tex_2d_dim);
+ if (gl_test_ext(gpu, "GL_EXT_texture3D", 21, 30))
+ get(GL_MAX_3D_TEXTURE_SIZE, &limits->max_tex_3d_dim);
+ // There's no equivalent limit for 1D textures for whatever reason, so
+ // just set it to the same as the 2D limit
+ if (p->gl_ver >= 21)
+ limits->max_tex_1d_dim = limits->max_tex_2d_dim;
+ limits->buf_transfer = true;
+
+ if (p->gl_ver || p->gles_ver >= 30) {
+ get(GL_MAX_FRAGMENT_UNIFORM_COMPONENTS, &limits->max_variable_comps);
+ } else {
+ // fallback for GLES 2.0, which doesn't have max_comps
+ get(GL_MAX_FRAGMENT_UNIFORM_VECTORS, &limits->max_variable_comps);
+ limits->max_variable_comps *= 4;
+ }
+
+ if (glsl->compute) {
+ for (int i = 0; i < 3; i++)
+ geti(GL_MAX_COMPUTE_WORK_GROUP_COUNT, i, &limits->max_dispatch[i]);
+ }
+
+ // Query import/export support
+ p->egl_dpy = params->egl_display;
+ p->egl_ctx = params->egl_context;
+ p->has_egl_storage = pl_opengl_has_ext(p->gl, "GL_EXT_EGL_image_storage");
+ p->has_egl_import = pl_opengl_has_ext(p->gl, "GL_OES_EGL_image_external");
+ gpu->export_caps.tex = tex_handle_caps(gpu, false);
+ gpu->import_caps.tex = tex_handle_caps(gpu, true);
+
+ if (p->egl_dpy) {
+ p->has_modifiers = pl_opengl_has_ext(p->gl,
+ "EGL_EXT_image_dma_buf_import_modifiers");
+ }
+
+ if (pl_opengl_has_ext(pl_gl, "GL_AMD_pinned_memory")) {
+ gpu->import_caps.buf |= PL_HANDLE_HOST_PTR;
+ gpu->limits.align_host_ptr = get_page_size();
+ }
+
+ // Cache some internal capability checks
+ p->has_vao = gl_test_ext(gpu, "GL_ARB_vertex_array_object", 30, 0);
+ p->has_invalidate_fb = gl_test_ext(gpu, "GL_ARB_invalidate_subdata", 43, 30);
+ p->has_invalidate_tex = gl_test_ext(gpu, "GL_ARB_invalidate_subdata", 43, 0);
+ p->has_queries = gl_test_ext(gpu, "GL_ARB_timer_query", 33, 0);
+ p->has_storage = gl_test_ext(gpu, "GL_ARB_shader_image_load_store", 42, 0);
+ p->has_readback = true;
+
+ if (p->has_readback && p->gles_ver) {
+ GLuint fbo = 0, tex = 0;
+ GLint read_type = 0, read_fmt = 0;
+ gl->GenTextures(1, &tex);
+ gl->BindTexture(GL_TEXTURE_2D, tex);
+ gl->GenFramebuffers(1, &fbo);
+ gl->TexImage2D(GL_TEXTURE_2D, 0, GL_R8, 64, 64, 0, GL_RED,
+ GL_UNSIGNED_BYTE, NULL);
+ gl->BindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
+ gl->FramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
+ GL_TEXTURE_2D, tex, 0);
+ gl->GetIntegerv(GL_IMPLEMENTATION_COLOR_READ_TYPE, &read_type);
+ gl->GetIntegerv(GL_IMPLEMENTATION_COLOR_READ_FORMAT, &read_fmt);
+ if (read_type != GL_UNSIGNED_BYTE || read_fmt != GL_RED) {
+ PL_INFO(gpu, "GPU does not seem to support lossless texture "
+ "readback, restricting readback capabilities! This is a "
+ "GLES/driver limitation, there is little we can do to "
+ "work around it.");
+ p->has_readback = false;
+ }
+ gl->BindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
+ gl->BindTexture(GL_TEXTURE_2D, 0);
+ gl->DeleteFramebuffers(1, &fbo);
+ gl->DeleteTextures(1, &tex);
+ }
+
+ // We simply don't know, so make up some values
+ limits->align_tex_xfer_offset = 32;
+ limits->align_tex_xfer_pitch = 4;
+ limits->fragment_queues = 1;
+ limits->compute_queues = glsl->compute ? 1 : 0;
+
+ if (!gl_check_err(gpu, "pl_gpu_create_gl")) {
+ PL_WARN(gpu, "Encountered errors while detecting GPU capabilities... "
+ "ignoring, but expect limitations/issues");
+ p->failed = false;
+ }
+
+ // Filter out error messages during format probing
+ pl_log_level_cap(gpu->log, PL_LOG_INFO);
+ bool formats_ok = gl_setup_formats(gpu);
+ pl_log_level_cap(gpu->log, PL_LOG_NONE);
+ if (!formats_ok)
+ goto error;
+
+ return pl_gpu_finalize(gpu);
+
+error:
+ gl_gpu_destroy(gpu);
+ return NULL;
+}
+
+void gl_buf_destroy(pl_gpu gpu, pl_buf buf)
+{
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ if (!MAKE_CURRENT()) {
+ PL_ERR(gpu, "Failed uninitializing buffer, leaking resources!");
+ return;
+ }
+
+ struct pl_buf_gl *buf_gl = PL_PRIV(buf);
+ if (buf_gl->fence)
+ gl->DeleteSync(buf_gl->fence);
+
+ if (buf_gl->mapped) {
+ gl->BindBuffer(GL_COPY_WRITE_BUFFER, buf_gl->buffer);
+ gl->UnmapBuffer(GL_COPY_WRITE_BUFFER);
+ gl->BindBuffer(GL_COPY_WRITE_BUFFER, 0);
+ }
+
+ gl->DeleteBuffers(1, &buf_gl->buffer);
+ gl_check_err(gpu, "gl_buf_destroy");
+ RELEASE_CURRENT();
+ pl_free((void *) buf);
+}
+
+pl_buf gl_buf_create(pl_gpu gpu, const struct pl_buf_params *params)
+{
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ if (!MAKE_CURRENT())
+ return NULL;
+
+ struct pl_buf_t *buf = pl_zalloc_obj(NULL, buf, struct pl_buf_gl);
+ buf->params = *params;
+ buf->params.initial_data = NULL;
+
+ struct pl_gl *p = PL_PRIV(gpu);
+ struct pl_buf_gl *buf_gl = PL_PRIV(buf);
+ buf_gl->id = ++p->buf_id;
+
+ // Just use this since the generic GL_BUFFER doesn't work
+ GLenum target = GL_ARRAY_BUFFER;
+ const void *data = params->initial_data;
+ size_t total_size = params->size;
+ bool import = false;
+
+ if (params->import_handle == PL_HANDLE_HOST_PTR) {
+ const struct pl_shared_mem *shmem = &params->shared_mem;
+ target = GL_EXTERNAL_VIRTUAL_MEMORY_BUFFER_AMD;
+
+ data = shmem->handle.ptr;
+ buf_gl->offset = shmem->offset;
+ total_size = shmem->size;
+ import = true;
+
+ if (params->host_mapped)
+ buf->data = (uint8_t *) data + buf_gl->offset;
+
+ if (buf_gl->offset > 0 && params->drawable) {
+ PL_ERR(gpu, "Cannot combine non-aligned host pointer imports with "
+ "drawable (vertex) buffers! This is a design limitation, "
+ "open an issue if you absolutely need this.");
+ goto error;
+ }
+ }
+
+ gl->GenBuffers(1, &buf_gl->buffer);
+ gl->BindBuffer(target, buf_gl->buffer);
+
+ if (gl_test_ext(gpu, "GL_ARB_buffer_storage", 44, 0) && !import) {
+
+ GLbitfield mapflags = 0, storflags = 0;
+ if (params->host_writable)
+ storflags |= GL_DYNAMIC_STORAGE_BIT;
+ if (params->host_mapped) {
+ mapflags |= GL_MAP_READ_BIT | GL_MAP_WRITE_BIT |
+ GL_MAP_PERSISTENT_BIT | GL_MAP_COHERENT_BIT;
+ }
+ if (params->memory_type == PL_BUF_MEM_HOST)
+ storflags |= GL_CLIENT_STORAGE_BIT; // hopefully this works
+
+ gl->BufferStorage(target, total_size, data, storflags | mapflags);
+
+ if (params->host_mapped) {
+ buf_gl->mapped = true;
+ buf->data = gl->MapBufferRange(target, buf_gl->offset, params->size,
+ mapflags);
+ if (!buf->data) {
+ gl->BindBuffer(target, 0);
+ if (!gl_check_err(gpu, "gl_buf_create: map"))
+ PL_ERR(gpu, "Failed mapping buffer: unknown reason");
+ goto error;
+ }
+ }
+
+ } else {
+
+ // Make a random guess based on arbitrary criteria we can't know
+ GLenum hint = GL_STREAM_DRAW;
+ if (params->initial_data && !params->host_writable && !params->host_mapped)
+ hint = GL_STATIC_DRAW;
+ if (params->host_readable && !params->host_writable && !params->host_mapped)
+ hint = GL_STREAM_READ;
+ if (params->storable)
+ hint = GL_DYNAMIC_COPY;
+
+ gl->BufferData(target, total_size, data, hint);
+
+ if (import && gl->GetError() == GL_INVALID_OPERATION) {
+ PL_ERR(gpu, "Failed importing host pointer!");
+ goto error;
+ }
+
+ }
+
+ gl->BindBuffer(target, 0);
+ if (!gl_check_err(gpu, "gl_buf_create"))
+ goto error;
+
+ if (params->storable) {
+ buf_gl->barrier = GL_BUFFER_UPDATE_BARRIER_BIT | // for buf_copy etc.
+ GL_PIXEL_BUFFER_BARRIER_BIT | // for tex_upload
+ GL_SHADER_STORAGE_BARRIER_BIT;
+
+ if (params->host_mapped)
+ buf_gl->barrier |= GL_CLIENT_MAPPED_BUFFER_BARRIER_BIT;
+ if (params->uniform)
+ buf_gl->barrier |= GL_UNIFORM_BARRIER_BIT;
+ if (params->drawable)
+ buf_gl->barrier |= GL_VERTEX_ATTRIB_ARRAY_BARRIER_BIT;
+ }
+
+ RELEASE_CURRENT();
+ return buf;
+
+error:
+ gl_buf_destroy(gpu, buf);
+ RELEASE_CURRENT();
+ return NULL;
+}
+
+bool gl_buf_poll(pl_gpu gpu, pl_buf buf, uint64_t timeout)
+{
+ const gl_funcs *gl = gl_funcs_get(gpu);
+
+ // Non-persistently mapped buffers are always implicitly reusable in OpenGL,
+ // the implementation will create more buffers under the hood if needed.
+ if (!buf->data)
+ return false;
+
+ if (!MAKE_CURRENT())
+ return true; // conservative guess
+
+ struct pl_buf_gl *buf_gl = PL_PRIV(buf);
+ if (buf_gl->fence) {
+ GLenum res = gl->ClientWaitSync(buf_gl->fence,
+ timeout ? GL_SYNC_FLUSH_COMMANDS_BIT : 0,
+ timeout);
+ if (res == GL_ALREADY_SIGNALED || res == GL_CONDITION_SATISFIED) {
+ gl->DeleteSync(buf_gl->fence);
+ buf_gl->fence = NULL;
+ }
+ }
+
+ gl_poll_callbacks(gpu);
+ RELEASE_CURRENT();
+ return !!buf_gl->fence;
+}
+
+void gl_buf_write(pl_gpu gpu, pl_buf buf, size_t offset,
+ const void *data, size_t size)
+{
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ if (!MAKE_CURRENT())
+ return;
+
+ struct pl_buf_gl *buf_gl = PL_PRIV(buf);
+ gl->BindBuffer(GL_ARRAY_BUFFER, buf_gl->buffer);
+ gl->BufferSubData(GL_ARRAY_BUFFER, buf_gl->offset + offset, size, data);
+ gl->BindBuffer(GL_ARRAY_BUFFER, 0);
+ gl_check_err(gpu, "gl_buf_write");
+ RELEASE_CURRENT();
+}
+
+bool gl_buf_read(pl_gpu gpu, pl_buf buf, size_t offset,
+ void *dest, size_t size)
+{
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ if (!MAKE_CURRENT())
+ return false;
+
+ struct pl_buf_gl *buf_gl = PL_PRIV(buf);
+ gl->BindBuffer(GL_ARRAY_BUFFER, buf_gl->buffer);
+ gl->GetBufferSubData(GL_ARRAY_BUFFER, buf_gl->offset + offset, size, dest);
+ gl->BindBuffer(GL_ARRAY_BUFFER, 0);
+ bool ok = gl_check_err(gpu, "gl_buf_read");
+ RELEASE_CURRENT();
+ return ok;
+}
+
+void gl_buf_copy(pl_gpu gpu, pl_buf dst, size_t dst_offset,
+ pl_buf src, size_t src_offset, size_t size)
+{
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ if (!MAKE_CURRENT())
+ return;
+
+ struct pl_buf_gl *src_gl = PL_PRIV(src);
+ struct pl_buf_gl *dst_gl = PL_PRIV(dst);
+ gl->BindBuffer(GL_COPY_READ_BUFFER, src_gl->buffer);
+ gl->BindBuffer(GL_COPY_WRITE_BUFFER, dst_gl->buffer);
+ gl->CopyBufferSubData(GL_COPY_READ_BUFFER, GL_COPY_WRITE_BUFFER,
+ src_gl->offset + src_offset,
+ dst_gl->offset + dst_offset, size);
+ gl_check_err(gpu, "gl_buf_copy");
+ RELEASE_CURRENT();
+}
+
+#define QUERY_OBJECT_NUM 8
+
+struct pl_timer_t {
+ GLuint query[QUERY_OBJECT_NUM];
+ int index_write; // next index to write to
+ int index_read; // next index to read from
+};
+
+static pl_timer gl_timer_create(pl_gpu gpu)
+{
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ struct pl_gl *p = PL_PRIV(gpu);
+ if (!p->has_queries || !MAKE_CURRENT())
+ return NULL;
+
+ pl_timer timer = pl_zalloc_ptr(NULL, timer);
+ gl->GenQueries(QUERY_OBJECT_NUM, timer->query);
+ RELEASE_CURRENT();
+ return timer;
+}
+
+static void gl_timer_destroy(pl_gpu gpu, pl_timer timer)
+{
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ if (!MAKE_CURRENT()) {
+ PL_ERR(gpu, "Failed uninitializing timer, leaking resources!");
+ return;
+ }
+
+ gl->DeleteQueries(QUERY_OBJECT_NUM, timer->query);
+ gl_check_err(gpu, "gl_timer_destroy");
+ RELEASE_CURRENT();
+ pl_free(timer);
+}
+
+static uint64_t gl_timer_query(pl_gpu gpu, pl_timer timer)
+{
+ if (timer->index_read == timer->index_write)
+ return 0; // no more unprocessed results
+
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ if (!MAKE_CURRENT())
+ return 0;
+
+ uint64_t res = 0;
+ GLuint query = timer->query[timer->index_read];
+ int avail = 0;
+ gl->GetQueryObjectiv(query, GL_QUERY_RESULT_AVAILABLE, &avail);
+ if (!avail)
+ goto done;
+ gl->GetQueryObjectui64v(query, GL_QUERY_RESULT, &res);
+
+ timer->index_read = (timer->index_read + 1) % QUERY_OBJECT_NUM;
+ // fall through
+
+done:
+ RELEASE_CURRENT();
+ return res;
+}
+
+void gl_timer_begin(pl_gpu gpu, pl_timer timer)
+{
+ if (!timer)
+ return;
+
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ gl->BeginQuery(GL_TIME_ELAPSED, timer->query[timer->index_write]);
+}
+
+void gl_timer_end(pl_gpu gpu, pl_timer timer)
+{
+ if (!timer)
+ return;
+
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ gl->EndQuery(GL_TIME_ELAPSED);
+
+ timer->index_write = (timer->index_write + 1) % QUERY_OBJECT_NUM;
+ if (timer->index_write == timer->index_read) {
+ // forcibly drop the least recent result to make space
+ timer->index_read = (timer->index_read + 1) % QUERY_OBJECT_NUM;
+ }
+}
+
+static void gl_gpu_flush(pl_gpu gpu)
+{
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ if (!MAKE_CURRENT())
+ return;
+
+ gl->Flush();
+ gl_check_err(gpu, "gl_gpu_flush");
+ RELEASE_CURRENT();
+}
+
+static void gl_gpu_finish(pl_gpu gpu)
+{
+ const gl_funcs *gl = gl_funcs_get(gpu);
+ if (!MAKE_CURRENT())
+ return;
+
+ gl->Finish();
+ gl_check_err(gpu, "gl_gpu_finish");
+ RELEASE_CURRENT();
+}
+
+static bool gl_gpu_is_failed(pl_gpu gpu)
+{
+ struct pl_gl *gl = PL_PRIV(gpu);
+ return gl->failed;
+}
+
+static const struct pl_gpu_fns pl_fns_gl = {
+ .destroy = gl_gpu_destroy,
+ .tex_create = gl_tex_create,
+ .tex_destroy = gl_tex_destroy,
+ .tex_invalidate = gl_tex_invalidate,
+ .tex_clear_ex = gl_tex_clear_ex,
+ .tex_blit = gl_tex_blit,
+ .tex_upload = gl_tex_upload,
+ .tex_download = gl_tex_download,
+ .buf_create = gl_buf_create,
+ .buf_destroy = gl_buf_destroy,
+ .buf_write = gl_buf_write,
+ .buf_read = gl_buf_read,
+ .buf_copy = gl_buf_copy,
+ .buf_poll = gl_buf_poll,
+ .desc_namespace = gl_desc_namespace,
+ .pass_create = gl_pass_create,
+ .pass_destroy = gl_pass_destroy,
+ .pass_run = gl_pass_run,
+ .timer_create = gl_timer_create,
+ .timer_destroy = gl_timer_destroy,
+ .timer_query = gl_timer_query,
+ .gpu_flush = gl_gpu_flush,
+ .gpu_finish = gl_gpu_finish,
+ .gpu_is_failed = gl_gpu_is_failed,
+};