Files
gpu-screen-recorder/src/cursor.c
2025-12-28 13:55:10 -08:00

145 lines
4.3 KiB
C

#include "../include/cursor.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <X11/extensions/Xfixes.h>
// TODO: Test cursor visibility with XFixesHideCursor
static bool gsr_cursor_set_from_x11_cursor_image(gsr_cursor *self, XFixesCursorImage *x11_cursor_image, bool *visible) {
uint8_t *cursor_data = NULL;
uint8_t *out = NULL;
*visible = false;
if(!x11_cursor_image)
goto err;
if(!x11_cursor_image->pixels)
goto err;
self->hotspot.x = x11_cursor_image->xhot;
self->hotspot.y = x11_cursor_image->yhot;
self->egl->glBindTexture(GL_TEXTURE_2D, self->texture_id);
self->size.x = x11_cursor_image->width;
self->size.y = x11_cursor_image->height;
const unsigned long *pixels = x11_cursor_image->pixels;
cursor_data = malloc(self->size.x * self->size.y * 4);
if(!cursor_data)
goto err;
out = cursor_data;
/* Un-premultiply alpha */
for(int y = 0; y < self->size.y; ++y) {
for(int x = 0; x < self->size.x; ++x) {
uint32_t pixel = *pixels++;
uint8_t *in = (uint8_t*)&pixel;
uint8_t alpha = in[3];
if(alpha == 0) {
alpha = 1;
} else {
*visible = true;
}
out[0] = (float)in[2] * 255.0/(float)alpha;
out[1] = (float)in[1] * 255.0/(float)alpha;
out[2] = (float)in[0] * 255.0/(float)alpha;
out[3] = in[3];
out += 4;
in += 4;
}
}
// TODO: glTextureSubImage2D if same size
self->egl->glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, self->size.x, self->size.y, 0, GL_RGBA, GL_UNSIGNED_BYTE, cursor_data);
free(cursor_data);
self->egl->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
self->egl->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
self->egl->glBindTexture(GL_TEXTURE_2D, 0);
XFree(x11_cursor_image);
return true;
err:
self->egl->glBindTexture(GL_TEXTURE_2D, 0);
if(x11_cursor_image)
XFree(x11_cursor_image);
return false;
}
int gsr_cursor_init(gsr_cursor *self, gsr_egl *egl, Display *display) {
int x_fixes_error_base = 0;
assert(egl);
assert(display);
memset(self, 0, sizeof(*self));
self->egl = egl;
self->display = display;
self->x_fixes_event_base = 0;
if(!XFixesQueryExtension(self->display, &self->x_fixes_event_base, &x_fixes_error_base)) {
fprintf(stderr, "gsr error: gsr_cursor_init: your X11 server is missing the XFixes extension\n");
gsr_cursor_deinit(self);
return -1;
}
self->egl->glGenTextures(1, &self->texture_id);
XFixesSelectCursorInput(self->display, DefaultRootWindow(self->display), XFixesDisplayCursorNotifyMask);
gsr_cursor_set_from_x11_cursor_image(self, XFixesGetCursorImage(self->display), &self->visible);
self->cursor_image_set = true;
return 0;
}
void gsr_cursor_deinit(gsr_cursor *self) {
if(!self->display)
return;
if(self->texture_id) {
self->egl->glDeleteTextures(1, &self->texture_id);
self->texture_id = 0;
}
if(self->display)
XFixesSelectCursorInput(self->display, DefaultRootWindow(self->display), 0);
self->display = NULL;
self->egl = NULL;
}
bool gsr_cursor_on_event(gsr_cursor *self, XEvent *xev) {
if(!self->display)
return false;
bool updated = false;
if(xev->type == self->x_fixes_event_base + XFixesCursorNotify) {
XFixesCursorNotifyEvent *cursor_notify_event = (XFixesCursorNotifyEvent*)xev;
if(cursor_notify_event->subtype == XFixesDisplayCursorNotify && cursor_notify_event->window == DefaultRootWindow(self->display)) {
self->cursor_image_set = false;
}
}
if(!self->cursor_image_set) {
self->cursor_image_set = true;
gsr_cursor_set_from_x11_cursor_image(self, XFixesGetCursorImage(self->display), &self->visible);
updated = true;
}
return updated;
}
void gsr_cursor_tick(gsr_cursor *self, Window relative_to) {
if(!self->display)
return;
Window dummy_window;
int dummy_i;
unsigned int dummy_u;
XQueryPointer(self->display, relative_to, &dummy_window, &dummy_window, &dummy_i, &dummy_i, &self->position.x, &self->position.y, &dummy_u);
}