diff options
| -rw-r--r-- | video/out/opengl/utils.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/video/out/opengl/utils.c b/video/out/opengl/utils.c index 9e786c6dcc..9870936bc5 100644 --- a/video/out/opengl/utils.c +++ b/video/out/opengl/utils.c @@ -232,7 +232,7 @@ void gl_vao_draw_data(struct gl_vao *vao, GLenum prim, void *ptr, size_t num) if (ptr) { gl->BindBuffer(GL_ARRAY_BUFFER, vao->buffer); - gl->BufferData(GL_ARRAY_BUFFER, num * vao->stride, ptr, GL_DYNAMIC_DRAW); + gl->BufferData(GL_ARRAY_BUFFER, num * vao->stride, ptr, GL_STREAM_DRAW); gl->BindBuffer(GL_ARRAY_BUFFER, 0); } @@ -1328,8 +1328,17 @@ void gl_pbo_upload_tex(struct gl_pbo_upload *pbo, GL *gl, bool use_pbo, pbo->buffer_size = buffer_size; gl->GenBuffers(1, &pbo->buffer); gl->BindBuffer(GL_PIXEL_UNPACK_BUFFER, pbo->buffer); + // Magic time: Because we memcpy once from RAM to the buffer, and then + // the GPU needs to read from this anyway, we actually *don't* want + // this buffer to be allocated in RAM. If we allocate it in VRAM + // instead, we can reduce this to a single copy: from RAM into VRAM. + // Unfortunately, drivers e.g. nvidia will think GL_STREAM_DRAW is best + // allocated on host memory instead of device memory, so we lie about + // the usage to fool the driver into giving us a buffer in VRAM instead + // of RAM, which can be significantly faster for our use case. + // Seriously, fuck OpenGL. gl->BufferData(GL_PIXEL_UNPACK_BUFFER, NUM_PBO_BUFFERS * buffer_size, - NULL, GL_DYNAMIC_COPY); + NULL, GL_STREAM_COPY); } size_t offset = buffer_size * pbo->index; |