read surface size from shm

osd.c

@@ -317,8 +317,8 @@ static const display_info_t fhd_display_info = {
 
 char font_2_name[256];
 
-uint16_t OVERLAY_WIDTH =1280;
-uint16_t OVERLAY_HEIGHT =720;
+uint16_t OVERLAY_WIDTH =1800;
+uint16_t OVERLAY_HEIGHT =1000;
 
 
 static displayport_vtable_t *display_driver;
@@ -1973,6 +1973,7 @@ static void InitMSPHook(){
         if (DrawOSD)
             Init_x86(&OVERLAY_WIDTH, &OVERLAY_HEIGHT);
         height=OVERLAY_HEIGHT;
+        printf("OSD is %ix%i pixels\n",OVERLAY_WIDTH,OVERLAY_HEIGHT);
     #endif
 
     //Get video resolution

osd/util/Render_Rockchip.c

@@ -21,32 +21,77 @@ cairo_surface_t* surface=NULL;
 cairo_surface_t* image_surface = NULL;
 cairo_t* cr=NULL;
 Pixmap backbuffer_pixmap;
-cairo_surface_t* backbuffer_surface;
 
+// Define the shared memory region structure
+typedef struct {
+    uint16_t width;  // Image width
+    uint16_t height; // Image height
+    unsigned char data[]; // Flexible array for image data
+} SharedMemoryRegion;
 
 extern int AHI_TiltY;
 int Init_x86(uint16_t *width, uint16_t *height) {
     // Create shared memory region
 
+    const char *shm_name = "msposd"; // Name of the shared memory region
+
     // Open the shared memory segment
-    int shm_fd = shm_open("msposd", O_RDWR, 0666);
+    int shm_fd = shm_open(shm_name, O_RDWR, 0666);
     if (shm_fd == -1) {
-    	perror("Failed to open shared memory");
+        perror("Failed to open shared memory");
+        return -1;
+    }
+
+    // Map just the header to read width and height
+    size_t header_size = sizeof(SharedMemoryRegion);
+    SharedMemoryRegion *shm_region = (SharedMemoryRegion *) mmap(0, header_size, PROT_READ, MAP_SHARED, shm_fd, 0);
+    if (shm_region == MAP_FAILED) {
+        perror("Failed to map shared memory header");
+        close(shm_fd);
+        return -1;
+    }
+
+    // Validate width and height (optional)
+    if (shm_region->width <= 0 || shm_region->width <= 0) {
+        fprintf(stderr, "Invalid width or height in shared memory\n");
+        munmap(shm_region, header_size);
+        close(shm_fd);
+        return -1;
+    }
+
+    int shm_width = shm_region->width;
+    int shm_height = shm_region->height;
+    *width = shm_region->width;
+    *height = shm_region->height;
+
+    printf("Surface is %ix%i pixels\n",shm_width,shm_height);
+
+    // Unmap the header (optional, as we'll remap everything)
+    munmap(shm_region, header_size);
+
+    // Calculate the total size of shared memory
+    size_t shm_size = header_size + (shm_width * shm_height * 4); // Header + Image data
+
+    // Remap the entire shared memory region (header + image data)
+    shm_region = (SharedMemoryRegion *) mmap(0, shm_size, PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, 0);
+    if (shm_region == MAP_FAILED) {
+        perror("Failed to remap shared memory");
+        close(shm_fd);
+        return -1;
     }
 
-    // Map the shared memory to the process's address space
-    size_t shm_size = (*width) * (*height) * 4; // 4 bytes per pixel (RGBA)
-    unsigned char *shm_data = (unsigned char*) mmap(0, shm_size, PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, 0);
-    if (shm_data == MAP_FAILED) {
-    	perror("Failed to map shared memory");
-    	close(shm_fd);
+    // Create a Cairo surface for the image data
+    surface = cairo_image_surface_create_for_data(
+        shm_region->data, CAIRO_FORMAT_ARGB32, shm_width, shm_height, shm_width * 4);
+    if (cairo_surface_status(surface) != CAIRO_STATUS_SUCCESS) {
+        fprintf(stderr, "Failed to create Cairo surface\n");
+        munmap(shm_region, shm_size);
+        close(shm_fd);
+        return -1;
     }
 
-    // Create a Cairo image surface on the shared memory buffer
-    cairo_surface_t *surface = cairo_image_surface_create_for_data(
-        shm_data, CAIRO_FORMAT_ARGB32, (*width) , (*height), (*width) * 4
-    );
-    cr = cairo_create(surface);        
+    // Create a Cairo context
+    cr = cairo_create(surface);  
 
 }