From ba6e917b49fcb192bc658557742106e29159dff7 Mon Sep 17 00:00:00 2001 From: Michael Maltese Date: Sun, 5 Mar 2017 15:34:30 -0800 Subject: OGL: implement Bounding Box on systems w/o SSBO MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This commit should have zero performance effect if SSBOs are supported. If they aren't (e.g. on all Macs), this commit alters FramebufferManager to attach a new stencil buffer and VertexManager to draw to it when bounding box is active. `BBoxRead` gets the pixel data from the buffer and dumbly loops through it to find the bounding box. This patch can run Paper Mario: The Thousand-Year Door at almost full speed (50–60 FPS) without Dual-Core enabled for all common bounding box-using actions I tested (going through pipes, Plane Mode, Paper Mode, Prof. Frankly's gate, combat, walking around the overworld, etc.) on my computer (macOS 10.12.3, 2.8 GHz Intel Core i7, 16 GB 1600 MHz DDR3, and Intel Iris 1536 MB). A few more demanding scenes (e.g. the self-building bridge on the way to Petalburg) slow to ~15% of their speed without this patch (though they don't run quite at full speed even on master). The slowdown is caused almost solely by `glReadPixels` in `OGL::BoundingBox::Get`. Other implementation ideas: - Use a stencil buffer that's separate from the depth buffer. This would require ARB_texture_stencil8 / OpenGL 4.4, which isn't available on macOS. - Use `glGetTexImage` instead of `glReadPixels`. This is ~5 FPS slower on my computer, presumably because it has to transfer the entire combined depth-stencil buffer instead of only the stencil data. Getting only stencil data from `glGetTexImage` requires ARB_texture_stencil8 / OpenGL 4.4, which (again) is not available on macOS. - Don't use a PBO, and use `glReadPixels` synchronously. This has no visible performance effect on my computer, and is theoretically slower. --- Source/Core/VideoBackends/OGL/main.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Source/Core/VideoBackends/OGL/main.cpp') diff --git a/Source/Core/VideoBackends/OGL/main.cpp b/Source/Core/VideoBackends/OGL/main.cpp index 3be16a6cbf..c1cf73f413 100644 --- a/Source/Core/VideoBackends/OGL/main.cpp +++ b/Source/Core/VideoBackends/OGL/main.cpp @@ -212,7 +212,7 @@ void VideoBackend::Video_Prepare() g_sampler_cache = std::make_unique(); static_cast(g_renderer.get())->Init(); TextureConverter::Init(); - BoundingBox::Init(); + BoundingBox::Init(g_renderer->GetTargetWidth(), g_renderer->GetTargetHeight()); } void VideoBackend::Shutdown() -- cgit v1.2.3