Refactor xcomposite into abstract capture api

Refactor c++ files into c files, more usable

src/capture/capture.c

@@ -1,17 +1,47 @@
 #include "../../include/capture/capture.h"
+#include <stdio.h>
 
-int gsr_capture_start(gsr_capture *cap) {
-    return cap->start(cap);
+int gsr_capture_start(gsr_capture *cap, AVCodecContext *video_codec_context) {
+    if(cap->started)
+        return -1;
+
+    int res = cap->start(cap, video_codec_context);
+    if(res == 0)
+        cap->started = true;
+
+    return res;
 }
 
-void gsr_capture_stop(gsr_capture *cap) {
-    cap->stop(cap);
+void gsr_capture_tick(gsr_capture *cap, AVCodecContext *video_codec_context, AVFrame **frame) {
+    if(!cap->started) {
+        fprintf(stderr, "gsr error: gsp_capture_tick failed: the gsr capture has not been started\n");
+        return;
+    }
+
+    if(cap->tick)
+        cap->tick(cap, video_codec_context, frame);
+}
+
+bool gsr_capture_should_stop(gsr_capture *cap, bool *err) {
+    if(!cap->started) {
+        fprintf(stderr, "gsr error: gsr_capture_should_stop failed: the gsr capture has not been started\n");
+        return false;
+    }
+
+    if(!cap->should_stop)
+        return false;
+
+    return cap->should_stop(cap, err);
 }
 
 int gsr_capture_capture(gsr_capture *cap, AVFrame *frame) {
+    if(!cap->started) {
+        fprintf(stderr, "gsr error: gsr_capture_capture failed: the gsr capture has not been started\n");
+        return -1;
+    }
     return cap->capture(cap, frame);
 }
 
-void gsr_capture_destroy(gsr_capture *cap) {
-    cap->destroy(cap);
+void gsr_capture_destroy(gsr_capture *cap, AVCodecContext *video_codec_context) {
+    cap->destroy(cap, video_codec_context);
 }

src/capture/nvfbc.c

@@ -1,10 +1,16 @@
 #include "../../include/capture/nvfbc.h"
 #include "../../external/NvFBC.h"
+#include "../../include/cuda.h"
 #include <dlfcn.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
+#include <X11/Xlib.h>
+#include <libavutil/hwcontext.h>
+#include <libavutil/hwcontext_cuda.h>
 #include <libavutil/frame.h>
+#include <libavutil/version.h>
+#include <libavcodec/avcodec.h>
 
 typedef struct {
     gsr_capture_nvfbc_params params;
@@ -14,6 +20,8 @@ typedef struct {
     PNVFBCCREATEINSTANCE nv_fbc_create_instance;
     NVFBC_API_FUNCTION_LIST nv_fbc_function_list;
     bool fbc_handle_created;
+
+    gsr_cuda cuda;
 } gsr_capture_nvfbc;
 
 #if defined(_WIN64) || defined(__LP64__)
@@ -28,13 +36,16 @@ static int max_int(int a, int b) {
 }
 
 /* Returns 0 on failure */
-static uint32_t get_output_id_from_display_name(NVFBC_RANDR_OUTPUT_INFO *outputs, uint32_t num_outputs, const char *display_name) {
+static uint32_t get_output_id_from_display_name(NVFBC_RANDR_OUTPUT_INFO *outputs, uint32_t num_outputs, const char *display_name, uint32_t *width, uint32_t *height) {
     if(!outputs)
         return 0;
 
     for(uint32_t i = 0; i < num_outputs; ++i) {
-        if(strcmp(outputs[i].name, display_name) == 0) 
+        if(strcmp(outputs[i].name, display_name) == 0) {
+            *width = outputs[i].trackedBox.w;
+            *height = outputs[i].trackedBox.h;
             return outputs[i].dwId;
+        }
     }
 
     return 0;
@@ -95,16 +106,78 @@ static bool gsr_capture_nvfbc_load_library(gsr_capture *cap) {
     return true;
 }
 
-static int gsr_capture_nvfbc_start(gsr_capture *cap) {
+#if LIBAVUTIL_VERSION_MAJOR < 57
+static AVBufferRef* dummy_hw_frame_init(int size) {
+    return av_buffer_alloc(size);
+}
+#else
+static AVBufferRef* dummy_hw_frame_init(size_t size) {
+    return av_buffer_alloc(size);
+}
+#endif
+
+static bool ffmpeg_create_cuda_contexts(gsr_capture_nvfbc *cap_nvfbc, AVCodecContext *video_codec_context) {
+    AVBufferRef *device_ctx = av_hwdevice_ctx_alloc(AV_HWDEVICE_TYPE_CUDA);
+    if(!device_ctx) {
+        fprintf(stderr, "gsr error: cuda_create_codec_context failed: failed to create hardware device context\n");
+        return false;
+    }
+
+    AVHWDeviceContext *hw_device_context = (AVHWDeviceContext*)device_ctx->data;
+    AVCUDADeviceContext *cuda_device_context = (AVCUDADeviceContext*)hw_device_context->hwctx;
+    cuda_device_context->cuda_ctx = cap_nvfbc->cuda.cu_ctx;
+    if(av_hwdevice_ctx_init(device_ctx) < 0) {
+        fprintf(stderr, "gsr error: cuda_create_codec_context failed: failed to create hardware device context\n");
+        av_buffer_unref(&device_ctx);
+        return false;
+    }
+
+    AVBufferRef *frame_context = av_hwframe_ctx_alloc(device_ctx);
+    if(!frame_context) {
+        fprintf(stderr, "gsr error: cuda_create_codec_context failed: failed to create hwframe context\n");
+        av_buffer_unref(&device_ctx);
+        return false;
+    }
+
+    AVHWFramesContext *hw_frame_context = (AVHWFramesContext*)frame_context->data;
+    hw_frame_context->width = video_codec_context->width;
+    hw_frame_context->height = video_codec_context->height;
+    hw_frame_context->sw_format = AV_PIX_FMT_0RGB32;
+    hw_frame_context->format = video_codec_context->pix_fmt;
+    hw_frame_context->device_ref = device_ctx;
+    hw_frame_context->device_ctx = (AVHWDeviceContext*)device_ctx->data;
+
+    hw_frame_context->pool = av_buffer_pool_init(1, dummy_hw_frame_init);
+    hw_frame_context->initial_pool_size = 1;
+
+    if (av_hwframe_ctx_init(frame_context) < 0) {
+        fprintf(stderr, "gsr error: cuda_create_codec_context failed: failed to initialize hardware frame context "
+                        "(note: ffmpeg version needs to be > 4.0)\n");
+        av_buffer_unref(&device_ctx);
+        av_buffer_unref(&frame_context);
+        return false;
+    }
+
+    video_codec_context->hw_device_ctx = device_ctx;
+    video_codec_context->hw_frames_ctx = frame_context;
+    return true;
+}
+
+static int gsr_capture_nvfbc_start(gsr_capture *cap, AVCodecContext *video_codec_context) {
     gsr_capture_nvfbc *cap_nvfbc = cap->priv;
+    if(!gsr_cuda_load(&cap_nvfbc->cuda))
+        return -1;
+
+    if(!gsr_capture_nvfbc_load_library(cap)) {
+        gsr_cuda_unload(&cap_nvfbc->cuda);
+        return -1;
+    }
+
     const uint32_t x = max_int(cap_nvfbc->params.pos.x, 0);
     const uint32_t y = max_int(cap_nvfbc->params.pos.y, 0);
     const uint32_t width = max_int(cap_nvfbc->params.size.x, 0);
     const uint32_t height = max_int(cap_nvfbc->params.size.y, 0);
 
-    if(!cap_nvfbc->library || !cap_nvfbc->params.display_to_capture || cap_nvfbc->fbc_handle_created)
-        return -1;
-
     const bool capture_region = (x > 0 || y > 0 || width > 0 || height > 0);
 
     NVFBCSTATUS status;
@@ -127,7 +200,7 @@ static int gsr_capture_nvfbc_start(gsr_capture *cap) {
         status = cap_nvfbc->nv_fbc_function_list.nvFBCCreateHandle(&cap_nvfbc->nv_fbc_handle, &create_params);
         if(status != NVFBC_SUCCESS) {
             fprintf(stderr, "gsr error: gsr_capture_nvfbc_start failed: %s\n", cap_nvfbc->nv_fbc_function_list.nvFBCGetLastErrorStr(cap_nvfbc->nv_fbc_handle));
-            return -1;
+            goto error_cleanup;
         }
     }
     cap_nvfbc->fbc_handle_created = true;
@@ -147,6 +220,8 @@ static int gsr_capture_nvfbc_start(gsr_capture *cap) {
         goto error_cleanup;
     }
 
+    uint32_t tracking_width = XWidthOfScreen(DefaultScreenOfDisplay(cap_nvfbc->params.dpy));
+    uint32_t tracking_height = XHeightOfScreen(DefaultScreenOfDisplay(cap_nvfbc->params.dpy));
     tracking_type = strcmp(cap_nvfbc->params.display_to_capture, "screen") == 0 ? NVFBC_TRACKING_SCREEN : NVFBC_TRACKING_OUTPUT;
     if(tracking_type == NVFBC_TRACKING_OUTPUT) {
         if(!status_params.bXRandRAvailable) {
@@ -159,7 +234,7 @@ static int gsr_capture_nvfbc_start(gsr_capture *cap) {
             goto error_cleanup;
         }
 
-        output_id = get_output_id_from_display_name(status_params.outputs, status_params.dwOutputNum, cap_nvfbc->params.display_to_capture);
+        output_id = get_output_id_from_display_name(status_params.outputs, status_params.dwOutputNum, cap_nvfbc->params.display_to_capture, &tracking_width, &tracking_height);
         if(output_id == 0) {
             fprintf(stderr, "gsr error: gsr_capture_nvfbc_start failed: display '%s' not found\n", cap_nvfbc->params.display_to_capture);
             goto error_cleanup;
@@ -198,6 +273,17 @@ static int gsr_capture_nvfbc_start(gsr_capture *cap) {
         goto error_cleanup;
     }
 
+    if(capture_region) {
+        video_codec_context->width = width & ~1;
+        video_codec_context->height = height & ~1;
+    } else {
+        video_codec_context->width = tracking_width & ~1;
+        video_codec_context->height = tracking_height & ~1;
+    }
+
+    if(!ffmpeg_create_cuda_contexts(cap_nvfbc, video_codec_context))
+        goto error_cleanup;
+
     return 0;
 
     error_cleanup:
@@ -215,17 +301,16 @@ static int gsr_capture_nvfbc_start(gsr_capture *cap) {
         cap_nvfbc->nv_fbc_function_list.nvFBCDestroyHandle(cap_nvfbc->nv_fbc_handle, &destroy_params);
         cap_nvfbc->fbc_handle_created = false;
     }
-    output_id = 0;
+
+    av_buffer_unref(&video_codec_context->hw_device_ctx);
+    av_buffer_unref(&video_codec_context->hw_frames_ctx);
+    gsr_cuda_unload(&cap_nvfbc->cuda);
     return -1;
 }
 
-static void gsr_capture_nvfbc_stop(gsr_capture *cap) {
+static void gsr_capture_nvfbc_destroy_session(gsr_capture *cap) {
     gsr_capture_nvfbc *cap_nvfbc = cap->priv;
 
-    /* Intentionally ignore failure on destroy */
-    if(!cap_nvfbc->nv_fbc_handle)
-        return;
-
     NVFBC_DESTROY_CAPTURE_SESSION_PARAMS destroy_capture_params;
     memset(&destroy_capture_params, 0, sizeof(destroy_capture_params));
     destroy_capture_params.dwVersion = NVFBC_DESTROY_CAPTURE_SESSION_PARAMS_VER;
@@ -241,8 +326,6 @@ static void gsr_capture_nvfbc_stop(gsr_capture *cap) {
 
 static int gsr_capture_nvfbc_capture(gsr_capture *cap, AVFrame *frame) {
     gsr_capture_nvfbc *cap_nvfbc = cap->priv;
-    if(!cap_nvfbc->library || !cap_nvfbc->fbc_handle_created)
-        return -1;
 
     CUdeviceptr cu_device_ptr = 0;
 
@@ -274,18 +357,19 @@ static int gsr_capture_nvfbc_capture(gsr_capture *cap, AVFrame *frame) {
     return 0;
 }
 
-static void gsr_capture_nvfbc_destroy(gsr_capture *cap) {
-    if(cap) {
-        gsr_capture_nvfbc *cap_nvfbc = cap->priv;
-        gsr_capture_nvfbc_stop(cap);
-        if(cap_nvfbc) {
-            dlclose(cap_nvfbc->library);
-            free((void*)cap_nvfbc->params.display_to_capture);
-            free(cap->priv);
-            cap->priv = NULL;
-        }
-        free(cap);
+static void gsr_capture_nvfbc_destroy(gsr_capture *cap, AVCodecContext *video_codec_context) {
+    gsr_capture_nvfbc *cap_nvfbc = cap->priv;
+    gsr_capture_nvfbc_destroy_session(cap);
+    av_buffer_unref(&video_codec_context->hw_device_ctx);
+    av_buffer_unref(&video_codec_context->hw_frames_ctx);
+    if(cap_nvfbc) {
+        gsr_cuda_unload(&cap_nvfbc->cuda);
+        dlclose(cap_nvfbc->library);
+        free((void*)cap_nvfbc->params.display_to_capture);
+        free(cap->priv);
+        cap->priv = NULL;
     }
+    free(cap);
 }
 
 gsr_capture* gsr_capture_nvfbc_create(const gsr_capture_nvfbc_params *params) {
@@ -294,6 +378,11 @@ gsr_capture* gsr_capture_nvfbc_create(const gsr_capture_nvfbc_params *params) {
         return NULL;
     }
 
+    if(!params->display_to_capture) {
+        fprintf(stderr, "gsr error: gsr_capture_nvfbc_create params.display_to_capture is NULL\n");
+        return NULL;
+    }
+
     gsr_capture *cap = calloc(1, sizeof(gsr_capture));
     if(!cap)
         return NULL;
@@ -317,16 +406,12 @@ gsr_capture* gsr_capture_nvfbc_create(const gsr_capture_nvfbc_params *params) {
     
     *cap = (gsr_capture) {
         .start = gsr_capture_nvfbc_start,
-        .stop = gsr_capture_nvfbc_stop,
+        .tick = NULL,
+        .should_stop = NULL,
         .capture = gsr_capture_nvfbc_capture,
         .destroy = gsr_capture_nvfbc_destroy,
         .priv = cap_nvfbc
     };
 
-    if(!gsr_capture_nvfbc_load_library(cap)) {
-        gsr_capture_nvfbc_destroy(cap);
-        return NULL;
-    }
-
     return cap;
 }

src/capture/xcomposite.c

@@ -0,0 +1,517 @@
+#include "../../include/capture/xcomposite.h"
+#include "../../include/gl.h"
+#include "../../include/cuda.h"
+#include "../../include/window_texture.h"
+#include "../../include/time.h"
+#include <X11/extensions/Xcomposite.h>
+#include <libavutil/hwcontext.h>
+#include <libavutil/hwcontext_cuda.h>
+#include <libavutil/frame.h>
+#include <libavcodec/avcodec.h>
+
+/* TODO: Proper error checks and cleanups */
+
+typedef struct {
+    gsr_capture_xcomposite_params params;
+    Display *dpy;
+    XEvent xev;
+    bool should_stop;
+    bool stop_is_error;
+    bool window_resized;
+    bool created_hw_frame;
+    double window_resize_timer;
+
+    vec2i window_size;
+    vec2i window_pos;
+
+    unsigned int target_texture_id;
+    vec2i texture_size;
+    Window composite_window;
+    WindowTexture window_texture;
+
+    CUgraphicsResource cuda_graphics_resource;
+    CUarray mapped_array;
+
+    gsr_gl gl;
+    gsr_cuda cuda;
+} gsr_capture_xcomposite;
+
+static int max_int(int a, int b) {
+    return a > b ? a : b;
+}
+
+static int min_int(int a, int b) {
+    return a < b ? a : b;
+}
+
+static void gsr_capture_xcomposite_stop(gsr_capture *cap, AVCodecContext *video_codec_context);
+
+static Window get_compositor_window(Display *display) {
+    Window overlay_window = XCompositeGetOverlayWindow(display, DefaultRootWindow(display));
+    XCompositeReleaseOverlayWindow(display, DefaultRootWindow(display));
+
+    Window root_window, parent_window;
+    Window *children = NULL;
+    unsigned int num_children = 0;
+    if(XQueryTree(display, overlay_window, &root_window, &parent_window, &children, &num_children) == 0)
+        return None;
+
+    Window compositor_window = None;
+    if(num_children == 1) {
+        compositor_window = children[0];
+        const int screen_width = XWidthOfScreen(DefaultScreenOfDisplay(display));
+        const int screen_height = XHeightOfScreen(DefaultScreenOfDisplay(display));
+
+        XWindowAttributes attr;
+        if(!XGetWindowAttributes(display, compositor_window, &attr) || attr.width != screen_width || attr.height != screen_height)
+            compositor_window = None;
+    }
+
+    if(children)
+        XFree(children);
+
+    return compositor_window;
+}
+
+/* TODO: check for glx swap control extension string (GLX_EXT_swap_control, etc) */
+static void set_vertical_sync_enabled(Display *display, Window window, gsr_gl *gl, bool enabled) {
+    int result = 0;
+
+    if(gl->glXSwapIntervalEXT) {
+        gl->glXSwapIntervalEXT(display, window, enabled ? 1 : 0);
+    } else if(gl->glXSwapIntervalMESA) {
+        result = gl->glXSwapIntervalMESA(enabled ? 1 : 0);
+    } else if(gl->glXSwapIntervalSGI) {
+        result = gl->glXSwapIntervalSGI(enabled ? 1 : 0);
+    } else {
+        static int warned = 0;
+        if (!warned) {
+            warned = 1;
+            fprintf(stderr, "Warning: setting vertical sync not supported\n");
+        }
+    }
+
+    if(result != 0)
+        fprintf(stderr, "Warning: setting vertical sync failed\n");
+}
+
+static bool cuda_register_opengl_texture(gsr_capture_xcomposite *cap_xcomp) {
+    CUresult res;
+    CUcontext old_ctx;
+    res = cap_xcomp->cuda.cuCtxPushCurrent_v2(cap_xcomp->cuda.cu_ctx);
+    res = cap_xcomp->cuda.cuGraphicsGLRegisterImage(
+        &cap_xcomp->cuda_graphics_resource, cap_xcomp->target_texture_id, GL_TEXTURE_2D,
+        CU_GRAPHICS_REGISTER_FLAGS_READ_ONLY);
+    if (res != CUDA_SUCCESS) {
+        const char *err_str = "unknown";
+        cap_xcomp->cuda.cuGetErrorString(res, &err_str);
+        fprintf(stderr,
+                "Error: cuGraphicsGLRegisterImage failed, error %s, texture "
+                "id: %u\n",
+                err_str, cap_xcomp->target_texture_id);
+        return false;
+    }
+
+    /* Get texture */
+    res = cap_xcomp->cuda.cuGraphicsResourceSetMapFlags(cap_xcomp->cuda_graphics_resource, CU_GRAPHICS_MAP_RESOURCE_FLAGS_READ_ONLY);
+    res = cap_xcomp->cuda.cuGraphicsMapResources(1, &cap_xcomp->cuda_graphics_resource, 0);
+
+    /* Map texture to cuda array */
+    res = cap_xcomp->cuda.cuGraphicsSubResourceGetMappedArray(&cap_xcomp->mapped_array, cap_xcomp->cuda_graphics_resource, 0, 0);
+    res = cap_xcomp->cuda.cuCtxPopCurrent_v2(&old_ctx);
+    return true;
+}
+
+static bool cuda_create_codec_context(gsr_capture_xcomposite *cap_xcomp, AVCodecContext *video_codec_context) {
+    CUcontext old_ctx;
+    cap_xcomp->cuda.cuCtxPushCurrent_v2(cap_xcomp->cuda.cu_ctx);
+
+    AVBufferRef *device_ctx = av_hwdevice_ctx_alloc(AV_HWDEVICE_TYPE_CUDA);
+    if(!device_ctx) {
+        fprintf(stderr, "Error: Failed to create hardware device context\n");
+        return false;
+    }
+
+    AVHWDeviceContext *hw_device_context = (AVHWDeviceContext*)device_ctx->data;
+    AVCUDADeviceContext *cuda_device_context = (AVCUDADeviceContext*)hw_device_context->hwctx;
+    cuda_device_context->cuda_ctx = cap_xcomp->cuda.cu_ctx;
+    if(av_hwdevice_ctx_init(device_ctx) < 0) {
+        fprintf(stderr, "Error: Failed to create hardware device context\n");
+        av_buffer_unref(&device_ctx);
+        cap_xcomp->cuda.cuCtxPopCurrent_v2(&old_ctx);
+        return false;
+    }
+
+    AVBufferRef *frame_context = av_hwframe_ctx_alloc(device_ctx);
+    if(!frame_context) {
+        fprintf(stderr, "Error: Failed to create hwframe context\n");
+        av_buffer_unref(&device_ctx);
+        cap_xcomp->cuda.cuCtxPopCurrent_v2(&old_ctx);
+        return false;
+    }
+
+    AVHWFramesContext *hw_frame_context =
+        (AVHWFramesContext *)frame_context->data;
+    hw_frame_context->width = video_codec_context->width;
+    hw_frame_context->height = video_codec_context->height;
+    hw_frame_context->sw_format = AV_PIX_FMT_0RGB32;
+    hw_frame_context->format = video_codec_context->pix_fmt;
+    hw_frame_context->device_ref = device_ctx;
+    hw_frame_context->device_ctx = (AVHWDeviceContext*)device_ctx->data;
+
+    if (av_hwframe_ctx_init(frame_context) < 0) {
+        fprintf(stderr, "Error: Failed to initialize hardware frame context "
+                        "(note: ffmpeg version needs to be > 4.0)\n");
+        av_buffer_unref(&device_ctx);
+        av_buffer_unref(&frame_context);
+        cap_xcomp->cuda.cuCtxPopCurrent_v2(&old_ctx);
+        return false;
+    }
+
+    video_codec_context->hw_device_ctx = device_ctx;
+    video_codec_context->hw_frames_ctx = frame_context;
+    return true;
+}
+
+static unsigned int gl_create_texture(gsr_capture_xcomposite *cap_xcomp, int width, int height) {
+    // Generating this second texture is needed because
+    // cuGraphicsGLRegisterImage cant be used with the texture that is mapped
+    // directly to the pixmap.
+    // TODO: Investigate if it's somehow possible to use the pixmap texture
+    // directly, this should improve performance since only less image copy is
+    // then needed every frame.
+    // Ignoring failure for now.. TODO: Show proper error
+    unsigned int texture_id = 0;
+    cap_xcomp->gl.glGenTextures(1, &texture_id);
+    cap_xcomp->gl.glBindTexture(GL_TEXTURE_2D, texture_id);
+    cap_xcomp->gl.glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
+
+    cap_xcomp->gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    cap_xcomp->gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    cap_xcomp->gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    cap_xcomp->gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+
+    cap_xcomp->gl.glBindTexture(GL_TEXTURE_2D, 0);
+    return texture_id;
+}
+
+static int gsr_capture_xcomposite_start(gsr_capture *cap, AVCodecContext *video_codec_context) {
+    gsr_capture_xcomposite *cap_xcomp = cap->priv;
+
+    XWindowAttributes attr;
+    if(!XGetWindowAttributes(cap_xcomp->dpy, cap_xcomp->params.window, &attr)) {
+        fprintf(stderr, "gsr error: gsr_capture_xcomposite_start failed: invalid window id: %lu\n", cap_xcomp->params.window);
+        return -1;
+    }
+
+    cap_xcomp->window_size.x = max_int(attr.width, 0);
+    cap_xcomp->window_size.y = max_int(attr.height, 0);
+    Window c;
+    XTranslateCoordinates(cap_xcomp->dpy, cap_xcomp->params.window, DefaultRootWindow(cap_xcomp->dpy), 0, 0, &cap_xcomp->window_pos.x, &cap_xcomp->window_pos.y, &c);
+
+    XSelectInput(cap_xcomp->dpy, cap_xcomp->params.window, StructureNotifyMask | ExposureMask);
+
+    if(!gsr_gl_load(&cap_xcomp->gl, cap_xcomp->dpy)) {
+        fprintf(stderr, "gsr error: gsr_capture_xcomposite_start: failed to load opengl\n");
+        return -1;
+    }
+
+    set_vertical_sync_enabled(cap_xcomp->dpy, cap_xcomp->gl.window, &cap_xcomp->gl, false);
+    if(window_texture_init(&cap_xcomp->window_texture, cap_xcomp->dpy, cap_xcomp->params.window, &cap_xcomp->gl) != 0) {
+        fprintf(stderr, "gsr error: gsr_capture_xcomposite_start: failed get window texture for window %ld\n", cap_xcomp->params.window);
+        gsr_gl_unload(&cap_xcomp->gl);
+        return -1;
+    }
+
+    cap_xcomp->gl.glBindTexture(GL_TEXTURE_2D, window_texture_get_opengl_texture_id(&cap_xcomp->window_texture));
+    cap_xcomp->texture_size.x = 0;
+    cap_xcomp->texture_size.y = 0;
+    cap_xcomp->gl.glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_WIDTH, &cap_xcomp->texture_size.x);
+    cap_xcomp->gl.glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_HEIGHT, &cap_xcomp->texture_size.y);
+    cap_xcomp->gl.glBindTexture(GL_TEXTURE_2D, 0);
+
+    cap_xcomp->texture_size.x = max_int(2, cap_xcomp->texture_size.x & ~1);
+    cap_xcomp->texture_size.y = max_int(2, cap_xcomp->texture_size.y & ~1);
+
+    cap_xcomp->target_texture_id = gl_create_texture(cap_xcomp, cap_xcomp->texture_size.x, cap_xcomp->texture_size.y);
+    if(cap_xcomp->target_texture_id == 0) {
+        fprintf(stderr, "gsr error: gsr_capture_xcomposite_start: failed to create opengl texture\n");
+        gsr_capture_xcomposite_stop(cap, video_codec_context);
+        return -1;
+    }
+
+    video_codec_context->width = cap_xcomp->texture_size.x;
+    video_codec_context->height = cap_xcomp->texture_size.y;
+
+    if(!gsr_cuda_load(&cap_xcomp->cuda)) {
+        gsr_capture_xcomposite_stop(cap, video_codec_context);
+        return -1;
+    }
+
+    if(!cuda_create_codec_context(cap_xcomp, video_codec_context)) {
+        gsr_capture_xcomposite_stop(cap, video_codec_context);
+        return -1;
+    }
+
+    if(!cuda_register_opengl_texture(cap_xcomp)) {
+        gsr_capture_xcomposite_stop(cap, video_codec_context);
+        return -1;
+    }
+
+    cap_xcomp->window_resize_timer = clock_get_monotonic_seconds();
+    return 0;
+}
+
+static void gsr_capture_xcomposite_stop(gsr_capture *cap, AVCodecContext *video_codec_context) {
+    gsr_capture_xcomposite *cap_xcomp = cap->priv;
+
+    window_texture_deinit(&cap_xcomp->window_texture);
+
+    if(cap_xcomp->target_texture_id) {
+        cap_xcomp->gl.glDeleteTextures(1, &cap_xcomp->target_texture_id);
+        cap_xcomp->target_texture_id = 0;
+    }
+
+    if(cap_xcomp->composite_window) {
+        XCompositeUnredirectWindow(cap_xcomp->dpy, cap_xcomp->composite_window, CompositeRedirectAutomatic);
+        cap_xcomp->composite_window = None;
+    }
+
+    av_buffer_unref(&video_codec_context->hw_device_ctx);
+    av_buffer_unref(&video_codec_context->hw_frames_ctx);
+
+    cap_xcomp->cuda.cuGraphicsUnmapResources(1, &cap_xcomp->cuda_graphics_resource, 0);
+    cap_xcomp->cuda.cuGraphicsUnregisterResource(cap_xcomp->cuda_graphics_resource);
+    gsr_cuda_unload(&cap_xcomp->cuda);
+
+    gsr_gl_unload(&cap_xcomp->gl);
+    if(cap_xcomp->dpy) {
+        XCloseDisplay(cap_xcomp->dpy);
+        cap_xcomp->dpy = NULL;
+    }
+}
+
+static void gsr_capture_xcomposite_tick(gsr_capture *cap, AVCodecContext *video_codec_context, AVFrame **frame) {
+    gsr_capture_xcomposite *cap_xcomp = cap->priv;
+
+    cap_xcomp->gl.glClear(GL_COLOR_BUFFER_BIT);
+
+    if(!cap_xcomp->created_hw_frame) {
+        CUcontext old_ctx;
+        cap_xcomp->cuda.cuCtxPushCurrent_v2(cap_xcomp->cuda.cu_ctx);
+
+        if(av_hwframe_get_buffer(video_codec_context->hw_frames_ctx, *frame, 0) < 0) {
+            fprintf(stderr, "gsr error: gsr_capture_xcomposite_tick: av_hwframe_get_buffer failed\n");
+            cap_xcomp->should_stop = true;
+            cap_xcomp->stop_is_error = true;
+            cap_xcomp->cuda.cuCtxPopCurrent_v2(&old_ctx);
+            return;
+        }
+
+        cap_xcomp->created_hw_frame = true;
+        cap_xcomp->cuda.cuCtxPopCurrent_v2(&old_ctx);
+    }
+
+    if(XCheckTypedWindowEvent(cap_xcomp->dpy, cap_xcomp->params.window, DestroyNotify, &cap_xcomp->xev)) {
+        cap_xcomp->should_stop = true;
+        cap_xcomp->stop_is_error = false;
+    }
+
+    if(XCheckTypedWindowEvent(cap_xcomp->dpy, cap_xcomp->params.window, Expose, &cap_xcomp->xev) && cap_xcomp->xev.xexpose.count == 0) {
+        cap_xcomp->window_resize_timer = clock_get_monotonic_seconds();
+        cap_xcomp->window_resized = true;
+    }
+
+    if(XCheckTypedWindowEvent(cap_xcomp->dpy, cap_xcomp->params.window, ConfigureNotify, &cap_xcomp->xev) && cap_xcomp->xev.xconfigure.window == cap_xcomp->params.window) {
+        while(XCheckTypedWindowEvent(cap_xcomp->dpy, cap_xcomp->params.window, ConfigureNotify, &cap_xcomp->xev)) {}
+        Window c;
+        XTranslateCoordinates(cap_xcomp->dpy, cap_xcomp->params.window, DefaultRootWindow(cap_xcomp->dpy), 0, 0, &cap_xcomp->xev.xconfigure.x, &cap_xcomp->xev.xconfigure.y, &c);
+        cap_xcomp->window_pos.x = cap_xcomp->xev.xconfigure.x;
+        cap_xcomp->window_pos.y = cap_xcomp->xev.xconfigure.y;
+
+        /* Window resize */
+        if(cap_xcomp->xev.xconfigure.width != cap_xcomp->window_size.x || cap_xcomp->xev.xconfigure.height != cap_xcomp->window_size.y) {
+            cap_xcomp->window_size.x = max_int(cap_xcomp->xev.xconfigure.width, 0);
+            cap_xcomp->window_size.y = max_int(cap_xcomp->xev.xconfigure.height, 0);
+            cap_xcomp->window_resize_timer = clock_get_monotonic_seconds();
+            cap_xcomp->window_resized = true;
+        }
+    }
+
+    const double window_resize_timeout = 1.0; // 1 second
+    if(cap_xcomp->window_resized && clock_get_monotonic_seconds() - cap_xcomp->window_resize_timer >= window_resize_timeout) {
+        cap_xcomp->window_resized = false;
+        fprintf(stderr, "Resize window!\n");
+        if(window_texture_on_resize(&cap_xcomp->window_texture) != 0) {
+            fprintf(stderr, "gsr error: gsr_capture_xcomposite_tick: window_texture_on_resize failed\n");
+            cap_xcomp->should_stop = true;
+            cap_xcomp->stop_is_error = true;
+            return;
+        }
+
+        cap_xcomp->gl.glBindTexture(GL_TEXTURE_2D, window_texture_get_opengl_texture_id(&cap_xcomp->window_texture));
+        cap_xcomp->texture_size.x = 0;
+        cap_xcomp->texture_size.y = 0;
+        cap_xcomp->gl.glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_WIDTH, &cap_xcomp->texture_size.x);
+        cap_xcomp->gl.glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_HEIGHT, &cap_xcomp->texture_size.y);
+        cap_xcomp->gl.glBindTexture(GL_TEXTURE_2D, 0);
+
+        cap_xcomp->texture_size.x = min_int(video_codec_context->width, max_int(2, cap_xcomp->texture_size.x & ~1));
+        cap_xcomp->texture_size.y = min_int(video_codec_context->height, max_int(2, cap_xcomp->texture_size.y & ~1));
+
+        cap_xcomp->gl.glBindTexture(GL_TEXTURE_2D, cap_xcomp->target_texture_id);
+        cap_xcomp->gl.glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, cap_xcomp->texture_size.x, cap_xcomp->texture_size.y, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
+        cap_xcomp->gl.glBindTexture(GL_TEXTURE_2D, 0);
+
+        CUcontext old_ctx;
+        CUresult res = cap_xcomp->cuda.cuCtxPushCurrent_v2(cap_xcomp->cuda.cu_ctx);
+
+        cap_xcomp->cuda.cuGraphicsUnmapResources(1, &cap_xcomp->cuda_graphics_resource, 0);
+        cap_xcomp->cuda.cuGraphicsUnregisterResource(cap_xcomp->cuda_graphics_resource);
+        res = cap_xcomp->cuda.cuGraphicsGLRegisterImage(&cap_xcomp->cuda_graphics_resource, cap_xcomp->target_texture_id, GL_TEXTURE_2D, CU_GRAPHICS_REGISTER_FLAGS_READ_ONLY);
+        if (res != CUDA_SUCCESS) {
+            const char *err_str = "unknown";
+            cap_xcomp->cuda.cuGetErrorString(res, &err_str);
+            fprintf(stderr, "gsr error: gsr_capture_xcomposite_tick: cuGraphicsGLRegisterImage failed, error %s, texture id: %u\n", err_str, cap_xcomp->target_texture_id);
+            cap_xcomp->should_stop = true;
+            cap_xcomp->stop_is_error = true;
+            res = cap_xcomp->cuda.cuCtxPopCurrent_v2(&old_ctx);
+            return;
+        }
+
+        res = cap_xcomp->cuda.cuGraphicsResourceSetMapFlags(cap_xcomp->cuda_graphics_resource, CU_GRAPHICS_MAP_RESOURCE_FLAGS_READ_ONLY);
+        res = cap_xcomp->cuda.cuGraphicsMapResources(1, &cap_xcomp->cuda_graphics_resource, 0);
+        res = cap_xcomp->cuda.cuGraphicsSubResourceGetMappedArray(&cap_xcomp->mapped_array, cap_xcomp->cuda_graphics_resource, 0, 0);
+
+        av_frame_free(frame);
+        *frame = av_frame_alloc();
+        if(!frame) {
+            fprintf(stderr, "gsr error: gsr_capture_xcomposite_tick: failed to allocate frame\n");
+            cap_xcomp->should_stop = true;
+            cap_xcomp->stop_is_error = true;
+            res = cap_xcomp->cuda.cuCtxPopCurrent_v2(&old_ctx);
+            return;
+        }
+        (*frame)->format = video_codec_context->pix_fmt;
+        (*frame)->width = video_codec_context->width;
+        (*frame)->height = video_codec_context->height;
+
+        if(av_hwframe_get_buffer(video_codec_context->hw_frames_ctx, *frame, 0) < 0) {
+            fprintf(stderr, "gsr error: gsr_capture_xcomposite_tick: av_hwframe_get_buffer failed\n");
+            cap_xcomp->should_stop = true;
+            cap_xcomp->stop_is_error = true;
+            res = cap_xcomp->cuda.cuCtxPopCurrent_v2(&old_ctx);
+            return;
+        }
+
+        // Make it completely black to clear unused parts
+        // TODO: cuMemsetD32?
+        res = cap_xcomp->cuda.cuMemsetD8_v2((CUdeviceptr)(*frame)->data[0], 0, (*frame)->width * (*frame)->height * 4);
+        res = cap_xcomp->cuda.cuCtxPopCurrent_v2(&old_ctx);
+    }
+}
+
+static bool gsr_capture_xcomposite_should_stop(gsr_capture *cap, bool *err) {
+    gsr_capture_xcomposite *cap_xcomp = cap->priv;
+    if(cap_xcomp->should_stop) {
+        if(err)
+            *err = cap_xcomp->stop_is_error;
+        return true;
+    }
+
+    if(err)
+        *err = false;
+    return false;
+}
+
+static int gsr_capture_xcomposite_capture(gsr_capture *cap, AVFrame *frame) {
+    gsr_capture_xcomposite *cap_xcomp = cap->priv;
+
+    // TODO: Use a framebuffer instead. glCopyImageSubData requires opengl 4.2
+    vec2i source_pos = { 0, 0 };
+    vec2i source_size = cap_xcomp->texture_size;
+
+    // Requires opengl 4.2... TODO: Replace with earlier opengl if opengl < 4.2.
+    cap_xcomp->gl.glCopyImageSubData(
+        window_texture_get_opengl_texture_id(&cap_xcomp->window_texture), GL_TEXTURE_2D, 0, source_pos.x, source_pos.y, 0,
+        cap_xcomp->target_texture_id, GL_TEXTURE_2D, 0, 0, 0, 0,
+        source_size.x, source_size.y, 1);
+    unsigned int err = cap_xcomp->gl.glGetError();
+    if(err != 0) {
+        static bool error_shown = false;
+        if(!error_shown) {
+            error_shown = true;
+            fprintf(stderr, "Error: glCopyImageSubData failed, gl error: %d\n", err);
+        }
+    }
+    cap_xcomp->gl.glXSwapBuffers(cap_xcomp->dpy, cap_xcomp->gl.window);
+    // TODO: Remove this copy, which is only possible by using nvenc directly and encoding window_pixmap.target_texture_id
+
+    frame->linesize[0] = frame->width * 4;
+
+    CUDA_MEMCPY2D memcpy_struct;
+    memcpy_struct.srcXInBytes = 0;
+    memcpy_struct.srcY = 0;
+    memcpy_struct.srcMemoryType = CU_MEMORYTYPE_ARRAY;
+
+    memcpy_struct.dstXInBytes = 0;
+    memcpy_struct.dstY = 0;
+    memcpy_struct.dstMemoryType = CU_MEMORYTYPE_DEVICE;
+
+    memcpy_struct.srcArray = cap_xcomp->mapped_array;
+    memcpy_struct.dstDevice = (CUdeviceptr)frame->data[0];
+    memcpy_struct.dstPitch = frame->linesize[0];
+    memcpy_struct.WidthInBytes = frame->width * 4;
+    memcpy_struct.Height = frame->height;
+    cap_xcomp->cuda.cuMemcpy2D_v2(&memcpy_struct);
+
+    return 0;
+}
+
+static void gsr_capture_xcomposite_destroy(gsr_capture *cap, AVCodecContext *video_codec_context) {
+    gsr_capture_xcomposite_stop(cap, video_codec_context);
+    if(cap->priv) {
+        free(cap->priv);
+        cap->priv = NULL;
+    }
+    free(cap);
+}
+
+gsr_capture* gsr_capture_xcomposite_create(const gsr_capture_xcomposite_params *params) {
+    if(!params) {
+        fprintf(stderr, "gsr error: gsr_capture_xcomposite_create params is NULL\n");
+        return NULL;
+    }
+
+    gsr_capture *cap = calloc(1, sizeof(gsr_capture));
+    if(!cap)
+        return NULL;
+
+    gsr_capture_xcomposite *cap_xcomp = calloc(1, sizeof(gsr_capture_xcomposite));
+    if(!cap_xcomp) {
+        free(cap);
+        return NULL;
+    }
+
+    Display *display = XOpenDisplay(NULL);
+    if(!display) {
+        fprintf(stderr, "gsr error: gsr_capture_xcomposite_create failed: XOpenDisplay failed\n");
+        free(cap);
+        free(cap_xcomp);
+        return NULL;
+    }
+
+    cap_xcomp->dpy = display;
+    cap_xcomp->params = *params;
+    
+    *cap = (gsr_capture) {
+        .start = gsr_capture_xcomposite_start,
+        .tick = gsr_capture_xcomposite_tick,
+        .should_stop = gsr_capture_xcomposite_should_stop,
+        .capture = gsr_capture_xcomposite_capture,
+        .destroy = gsr_capture_xcomposite_destroy,
+        .priv = cap_xcomp
+    };
+
+    return cap;
+}