/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ #include "config.h" #include "common/rect.h" #include "common/surface.h" #include #include #include #include #include #include #include #include #include #include #include /** * The width of an update which should be considered negible and thus * trivial overhead compared ot the cost of two updates. */ #define GUAC_SURFACE_NEGLIGIBLE_WIDTH 64 /** * The height of an update which should be considered negible and thus * trivial overhead compared ot the cost of two updates. */ #define GUAC_SURFACE_NEGLIGIBLE_HEIGHT 64 /** * The proportional increase in cost contributed by transfer and processing of * image data, compared to processing an equivalent amount of client-side * data. */ #define GUAC_SURFACE_DATA_FACTOR 16 /** * The base cost of every update. Each update should be considered to have * this starting cost, plus any additional cost estimated from its * content. */ #define GUAC_SURFACE_BASE_COST 4096 /** * An increase in cost is negligible if it is less than * 1/GUAC_SURFACE_NEGLIGIBLE_INCREASE of the old cost. */ #define GUAC_SURFACE_NEGLIGIBLE_INCREASE 4 /** * If combining an update because it appears to be follow a fill pattern, * the combined cost must not exceed * GUAC_SURFACE_FILL_PATTERN_FACTOR * (total uncombined cost). */ #define GUAC_SURFACE_FILL_PATTERN_FACTOR 3 /* Define cairo_format_stride_for_width() if missing */ #ifndef HAVE_CAIRO_FORMAT_STRIDE_FOR_WIDTH #define cairo_format_stride_for_width(format, width) (width*4) #endif /** * The JPEG image quality ('quantization') setting to use. Range 0-100 where * 100 is the highest quality/largest file size, and 0 is the lowest * quality/smallest file size. */ #define GUAC_SURFACE_JPEG_IMAGE_QUALITY 90 /** * The framerate which, if exceeded, indicates that JPEG is preferred. */ #define GUAC_COMMON_SURFACE_JPEG_FRAMERATE 3 /** * Minimum JPEG bitmap size (area). If the bitmap is smaller than this threshold, * it should be compressed as a PNG image to avoid the JPEG compression tax. */ #define GUAC_SURFACE_JPEG_MIN_BITMAP_SIZE 4096 /** * The WebP image quality ('quantization') setting to use. Range 0-100 where * 100 is the highest quality/largest file size, and 0 is the lowest * quality/smallest file size. */ #define GUAC_SURFACE_WEBP_IMAGE_QUALITY 90 /** * The JPEG compression min block size. This defines the optimal rectangle block * size factor for JPEG compression. Usually 8x8 would suffice, but use 16 to * reduce the occurrence of ringing artifacts further. */ #define GUAC_SURFACE_JPEG_BLOCK_SIZE 16 /** * The WebP compression min block size. This defines the optimal rectangle block * size factor for WebP compression. WebP does utilize variable block size, but * ensuring a block size factor reduces any noise on the image edges. */ #define GUAC_SURFACE_WEBP_BLOCK_SIZE 8 void guac_common_surface_move(guac_common_surface* surface, int x, int y) { pthread_mutex_lock(&surface->_lock); surface->x = x; surface->y = y; surface->location_dirty = 1; pthread_mutex_unlock(&surface->_lock); } void guac_common_surface_stack(guac_common_surface* surface, int z) { pthread_mutex_lock(&surface->_lock); surface->z = z; surface->location_dirty = 1; pthread_mutex_unlock(&surface->_lock); } void guac_common_surface_set_parent(guac_common_surface* surface, const guac_layer* parent) { pthread_mutex_lock(&surface->_lock); surface->parent = parent; surface->location_dirty = 1; pthread_mutex_unlock(&surface->_lock); } void guac_common_surface_set_opacity(guac_common_surface* surface, int opacity) { pthread_mutex_lock(&surface->_lock); surface->opacity = opacity; surface->opacity_dirty = 1; pthread_mutex_unlock(&surface->_lock); } /** * Updates the coordinates of the given rectangle to be within the bounds of * the given surface. * * @param surface The surface to use for clipping. * @param rect The rectangle to clip. * @param sx The X coordinate of the source rectangle, if any. * @param sy The Y coordinate of the source rectangle, if any. */ static void __guac_common_bound_rect(guac_common_surface* surface, guac_common_rect* rect, int* sx, int* sy) { guac_common_rect bounds_rect = { .x = 0, .y = 0, .width = surface->width, .height = surface->height }; int orig_x = rect->x; int orig_y = rect->y; guac_common_rect_constrain(rect, &bounds_rect); /* Update source X/Y if given */ if (sx != NULL) *sx += rect->x - orig_x; if (sy != NULL) *sy += rect->y - orig_y; } /** * Updates the coordinates of the given rectangle to be within the clipping * rectangle of the given surface, which must always be within the bounding * rectangle of the given surface. * * @param surface The surface to use for clipping. * @param rect The rectangle to clip. * @param sx The X coordinate of the source rectangle, if any. * @param sy The Y coordinate of the source rectangle, if any. */ static void __guac_common_clip_rect(guac_common_surface* surface, guac_common_rect* rect, int* sx, int* sy) { int orig_x = rect->x; int orig_y = rect->y; /* Just bound within surface if no clipping rectangle applied */ if (!surface->clipped) { __guac_common_bound_rect(surface, rect, sx, sy); return; } guac_common_rect_constrain(rect, &surface->clip_rect); /* Update source X/Y if given */ if (sx != NULL) *sx += rect->x - orig_x; if (sy != NULL) *sy += rect->y - orig_y; } /** * Returns whether a rectangle within the given surface contains only fully * opaque pixels. * * @param surface * The surface to check. * * @param rect * The rectangle to check. * * @return * Non-zero if the rectangle contains only fully opaque pixels, zero * otherwise. */ static int __guac_common_surface_is_opaque(guac_common_surface* surface, guac_common_rect* rect) { int x, y; int stride = surface ->stride; unsigned char* buffer = surface->buffer + (stride * rect->y) + (4 * rect->x); /* For each row */ for (y = 0; y < rect->height; y++) { /* Search for a non-opaque pixel */ uint32_t* current = (uint32_t*) buffer; for (x=0; x < rect->width; x++) { /* Rectangle is non-opaque if a single non-opaque pixel is found */ uint32_t color = *(current++); if ((color & 0xFF000000) != 0xFF000000) return 0; } /* Next row */ buffer += stride; } /* Rectangle is opaque */ return 1; } /** * Returns whether the given rectangle should be combined into the existing * dirty rectangle, to be eventually flushed as a "png" instruction. * * @param surface The surface to be queried. * @param rect The update rectangle. * @param rect_only Non-zero if this update, by its nature, contains only * metainformation about the update's rectangle, zero if * the update also contains image data. * @return Non-zero if the update should be combined with any existing update, * zero otherwise. */ static int __guac_common_should_combine(guac_common_surface* surface, const guac_common_rect* rect, int rect_only) { if (surface->dirty) { int combined_cost, dirty_cost, update_cost; /* Simulate combination */ guac_common_rect combined = surface->dirty_rect; guac_common_rect_extend(&combined, rect); /* Combine if result is still small */ if (combined.width <= GUAC_SURFACE_NEGLIGIBLE_WIDTH && combined.height <= GUAC_SURFACE_NEGLIGIBLE_HEIGHT) return 1; /* Estimate costs of the existing update, new update, and both combined */ combined_cost = GUAC_SURFACE_BASE_COST + combined.width * combined.height; dirty_cost = GUAC_SURFACE_BASE_COST + surface->dirty_rect.width * surface->dirty_rect.height; update_cost = GUAC_SURFACE_BASE_COST + rect->width * rect->height; /* Reduce cost if no image data */ if (rect_only) update_cost /= GUAC_SURFACE_DATA_FACTOR; /* Combine if cost estimate shows benefit */ if (combined_cost <= update_cost + dirty_cost) return 1; /* Combine if increase in cost is negligible */ if (combined_cost - dirty_cost <= dirty_cost / GUAC_SURFACE_NEGLIGIBLE_INCREASE) return 1; if (combined_cost - update_cost <= update_cost / GUAC_SURFACE_NEGLIGIBLE_INCREASE) return 1; /* Combine if we anticipate further updates, as this update follows a common fill pattern */ if (rect->x == surface->dirty_rect.x && rect->y == surface->dirty_rect.y + surface->dirty_rect.height) { if (combined_cost <= (dirty_cost + update_cost) * GUAC_SURFACE_FILL_PATTERN_FACTOR) return 1; } } /* Otherwise, do not combine */ return 0; } /** * Expands the dirty rect of the given surface to contain the rect described by the given * coordinates. * * @param surface The surface to mark as dirty. * @param rect The rectangle of the update which is dirtying the surface. */ static void __guac_common_mark_dirty(guac_common_surface* surface, const guac_common_rect* rect) { /* Ignore empty rects */ if (rect->width <= 0 || rect->height <= 0) return; /* If already dirty, update existing rect */ if (surface->dirty) guac_common_rect_extend(&surface->dirty_rect, rect); /* Otherwise init dirty rect */ else { surface->dirty_rect = *rect; surface->dirty = 1; } } /** * Calculate the current average framerate for a given area on the surface. * * @param surface * The surface on which the framerate will be calculated. * * @param rect * The rect containing the area for which the average framerate will be * calculated. * * @return * The average framerate of the given area, in frames per second. */ static unsigned int __guac_common_surface_calculate_framerate( guac_common_surface* surface, const guac_common_rect* rect) { int x, y; /* Calculate heat map dimensions */ int heat_width = GUAC_COMMON_SURFACE_HEAT_DIMENSION(surface->width); /* Calculate minimum X/Y coordinates intersecting given rect */ int min_x = rect->x / GUAC_COMMON_SURFACE_HEAT_CELL_SIZE; int min_y = rect->y / GUAC_COMMON_SURFACE_HEAT_CELL_SIZE; /* Calculate maximum X/Y coordinates intersecting given rect */ int max_x = min_x + (rect->width - 1) / GUAC_COMMON_SURFACE_HEAT_CELL_SIZE; int max_y = min_y + (rect->height - 1) / GUAC_COMMON_SURFACE_HEAT_CELL_SIZE; unsigned int sum_framerate = 0; unsigned int count = 0; /* Get start of buffer at given coordinates */ const guac_common_surface_heat_cell* heat_row = surface->heat_map + min_y * heat_width + min_x; /* Iterate over all the heat map cells for the area * and calculate the average framerate */ for (y = min_y; y < max_y; y++) { /* Get current row of heat map */ const guac_common_surface_heat_cell* heat_cell = heat_row; /* For each cell in subset of row */ for (x = min_x; x < max_x; x++) { /* Calculate indicies for latest and oldest history entries */ int oldest_entry = heat_cell->oldest_entry; int latest_entry = oldest_entry - 1; if (latest_entry < 0) latest_entry = GUAC_COMMON_SURFACE_HEAT_CELL_HISTORY_SIZE - 1; /* Calculate elapsed time covering entire history for this cell */ int elapsed_time = heat_cell->history[latest_entry] - heat_cell->history[oldest_entry]; /* Calculate and add framerate */ if (elapsed_time) sum_framerate += GUAC_COMMON_SURFACE_HEAT_CELL_HISTORY_SIZE * 1000 / elapsed_time; /* Next heat map cell */ heat_cell++; count++; } /* Next heat map row */ heat_row += heat_width; } /* Calculate the average framerate over entire rect */ if (count) return sum_framerate / count; return 0; } /** * Guesses whether a rectangle within a particular surface would be better * compressed as PNG or using a lossy format like JPEG. Positive values * indicate PNG is likely to be superior, while negative values indicate the * opposite. * * @param surface * The surface containing the image data to check. * * @param rect * The rect to check within the given surface. * * @return * Positive values if PNG compression is likely to perform better than * lossy alternatives, or negative values if PNG is likely to perform * worse. */ static int __guac_common_surface_png_optimality(guac_common_surface* surface, const guac_common_rect* rect) { int x, y; int num_same = 0; int num_different = 1; /* Get image/buffer metrics */ int width = rect->width; int height = rect->height; int stride = surface->stride; /* Get buffer from surface */ unsigned char* buffer = surface->buffer + rect->y * stride + rect->x * 4; /* Image must be at least 1x1 */ if (width < 1 || height < 1) return 0; /* For each row */ for (y = 0; y < height; y++) { uint32_t* row = (uint32_t*) buffer; uint32_t last_pixel = *(row++) | 0xFF000000; /* For each pixel in current row */ for (x = 1; x < width; x++) { /* Get next pixel */ uint32_t current_pixel = *(row++) | 0xFF000000; /* Update same/different counts according to pixel value */ if (current_pixel == last_pixel) num_same++; else num_different++; last_pixel = current_pixel; } /* Advance to next row */ buffer += stride; } /* Return rough approximation of optimality for PNG compression */ return 0x100 * num_same / num_different - 0x400; } /** * Returns whether the given rectangle would be optimally encoded as JPEG * rather than PNG. * * @param surface * The surface to be queried. * * @param rect * The rectangle to check. * * @return * Non-zero if the rectangle would be optimally encoded as JPEG, zero * otherwise. */ static int __guac_common_surface_should_use_jpeg(guac_common_surface* surface, const guac_common_rect* rect) { /* Calculate the average framerate for the given rect */ int framerate = __guac_common_surface_calculate_framerate(surface, rect); int rect_size = rect->width * rect->height; /* JPEG is preferred if: * - frame rate is high enough * - image size is large enough * - PNG is not more optimal based on image contents */ return framerate >= GUAC_COMMON_SURFACE_JPEG_FRAMERATE && rect_size > GUAC_SURFACE_JPEG_MIN_BITMAP_SIZE && __guac_common_surface_png_optimality(surface, rect) < 0; } /** * Returns whether the given rectangle would be optimally encoded as WebP * rather than PNG. * * @param surface * The surface to be queried. * * @param rect * The rectangle to check. * * @return * Non-zero if the rectangle would be optimally encoded as WebP, zero * otherwise. */ static int __guac_common_surface_should_use_webp(guac_common_surface* surface, const guac_common_rect* rect) { /* Do not use WebP if not supported */ if (!guac_client_supports_webp(surface->client)) return 0; /* Calculate the average framerate for the given rect */ int framerate = __guac_common_surface_calculate_framerate(surface, rect); /* WebP is preferred if: * - frame rate is high enough * - PNG is not more optimal based on image contents */ return framerate >= GUAC_COMMON_SURFACE_JPEG_FRAMERATE && __guac_common_surface_png_optimality(surface, rect) < 0; } /** * Updates the heat map cells which intersect the given rectangle using the * given timestamp. This timestamp, along with timestamps from past updates, * is used to calculate the framerate of each heat cell. * * @param surface * The surface containing the heat map cells to be updated. * * @param rect * The rectangle containing the heat map cells to be updated. * * @param time * The timestamp to use when updating the heat map cells which intersect * the given rectangle. */ static void __guac_common_surface_touch_rect(guac_common_surface* surface, guac_common_rect* rect, guac_timestamp time) { int x, y; /* Calculate heat map dimensions */ int heat_width = GUAC_COMMON_SURFACE_HEAT_DIMENSION(surface->width); /* Calculate minimum X/Y coordinates intersecting given rect */ int min_x = rect->x / GUAC_COMMON_SURFACE_HEAT_CELL_SIZE; int min_y = rect->y / GUAC_COMMON_SURFACE_HEAT_CELL_SIZE; /* Calculate maximum X/Y coordinates intersecting given rect */ int max_x = min_x + (rect->width - 1) / GUAC_COMMON_SURFACE_HEAT_CELL_SIZE; int max_y = min_y + (rect->height - 1) / GUAC_COMMON_SURFACE_HEAT_CELL_SIZE; /* Get start of buffer at given coordinates */ guac_common_surface_heat_cell* heat_row = surface->heat_map + min_y * heat_width + min_x; /* Update all heat map cells which intersect with rectangle */ for (y = min_y; y <= max_y; y++) { /* Get current row of heat map */ guac_common_surface_heat_cell* heat_cell = heat_row; /* For each cell in subset of row */ for (x = min_x; x <= max_x; x++) { /* Replace oldest entry with new timestamp */ heat_cell->history[heat_cell->oldest_entry] = time; /* Update to next oldest entry */ heat_cell->oldest_entry++; if (heat_cell->oldest_entry >= GUAC_COMMON_SURFACE_HEAT_CELL_HISTORY_SIZE) heat_cell->oldest_entry = 0; /* Advance to next heat map cell */ heat_cell++; } /* Next heat map row */ heat_row += heat_width; } } /** * Flushes the bitmap update currently described by the dirty rectangle within the * given surface to that surface's bitmap queue. There MUST be space within the * queue. * * @param surface The surface to flush. */ static void __guac_common_surface_flush_to_queue(guac_common_surface* surface) { guac_common_surface_bitmap_rect* rect; /* Do not flush if not dirty */ if (!surface->dirty) return; /* Add new rect to queue */ rect = &(surface->bitmap_queue[surface->bitmap_queue_length++]); rect->rect = surface->dirty_rect; rect->flushed = 0; /* Surface now flushed */ surface->dirty = 0; } /** * Flushes the given surface, drawing any pending operations on the remote * display. Surface properties are not flushed. * * @param surface * The surface to flush. */ static void __guac_common_surface_flush(guac_common_surface* surface); /** * Schedules a deferred flush of the given surface. This will not immediately * flush the surface to the client. Instead, the result of the flush is * added to a queue which is reinspected and combined (if possible) with other * deferred flushes during the call to guac_common_surface_flush(). * * @param surface The surface to flush. */ static void __guac_common_surface_flush_deferred(guac_common_surface* surface) { /* Do not flush if not dirty */ if (!surface->dirty) return; /* Flush if queue size has reached maximum (space is reserved for the final * dirty rect, as __guac_common_surface_flush() MAY add an additional rect * to the queue */ if (surface->bitmap_queue_length == GUAC_COMMON_SURFACE_QUEUE_SIZE-1) __guac_common_surface_flush(surface); /* Append dirty rect to queue */ __guac_common_surface_flush_to_queue(surface); } /** * Transfers a single uint32_t using the given transfer function. * * @param op The transfer function to use. * @param src The source of the uint32_t value. * @param dst THe destination which will hold the result of the transfer. * @return Non-zero if the destination value was changed, zero otherwise. */ static int __guac_common_surface_transfer_int(guac_transfer_function op, uint32_t* src, uint32_t* dst) { uint32_t orig = *dst; switch (op) { case GUAC_TRANSFER_BINARY_BLACK: *dst = 0xFF000000; break; case GUAC_TRANSFER_BINARY_WHITE: *dst = 0xFFFFFFFF; break; case GUAC_TRANSFER_BINARY_SRC: *dst = *src; break; case GUAC_TRANSFER_BINARY_DEST: /* NOP */ break; case GUAC_TRANSFER_BINARY_NSRC: *dst = ~(*src); break; case GUAC_TRANSFER_BINARY_NDEST: *dst = ~(*dst); break; case GUAC_TRANSFER_BINARY_AND: *dst = (*dst) & (*src); break; case GUAC_TRANSFER_BINARY_NAND: *dst = ~((*dst) & (*src)); break; case GUAC_TRANSFER_BINARY_OR: *dst = (*dst) | (*src); break; case GUAC_TRANSFER_BINARY_NOR: *dst = ~((*dst) | (*src)); break; case GUAC_TRANSFER_BINARY_XOR: *dst = (*dst) ^ (*src); break; case GUAC_TRANSFER_BINARY_XNOR: *dst = ~((*dst) ^ (*src)); break; case GUAC_TRANSFER_BINARY_NSRC_AND: *dst = (*dst) & ~(*src); break; case GUAC_TRANSFER_BINARY_NSRC_NAND: *dst = ~((*dst) & ~(*src)); break; case GUAC_TRANSFER_BINARY_NSRC_OR: *dst = (*dst) | ~(*src); break; case GUAC_TRANSFER_BINARY_NSRC_NOR: *dst = ~((*dst) | ~(*src)); break; } return *dst != orig; } /** * Assigns the given value to all pixels within a rectangle of the backing * surface of the given destination surface. The color of all pixels within the * rectangle, including the alpha component, is entirely replaced. * * @param dst * The destination surface. * * @param rect * The rectangle to draw. * * @param red * The red component of the color value to assign to all pixels within the * rectangle. * * @param green * The green component of the color value to assign to all pixels within * the rectangle. * * @param blue * The blue component of the color value to assign to all pixels within the * rectangle. * * @param alpha * The alpha component of the color value to assign to all pixels within * the rectangle. */ static void __guac_common_surface_set(guac_common_surface* dst, guac_common_rect* rect, int red, int green, int blue, int alpha) { int x, y; int dst_stride; unsigned char* dst_buffer; uint32_t color = (alpha << 24) | (red << 16) | (green << 8) | blue; int min_x = rect->width - 1; int min_y = rect->height - 1; int max_x = 0; int max_y = 0; dst_stride = dst->stride; dst_buffer = dst->buffer + (dst_stride * rect->y) + (4 * rect->x); /* For each row */ for (y=0; y < rect->height; y++) { uint32_t* dst_current = (uint32_t*) dst_buffer; /* Set row */ for (x=0; x < rect->width; x++) { uint32_t old_color = *dst_current; if (old_color != color) { if (x < min_x) min_x = x; if (y < min_y) min_y = y; if (x > max_x) max_x = x; if (y > max_y) max_y = y; *dst_current = color; } dst_current++; } /* Next row */ dst_buffer += dst_stride; } /* Restrict destination rect to only updated pixels */ if (max_x >= min_x && max_y >= min_y) { rect->x += min_x; rect->y += min_y; rect->width = max_x - min_x + 1; rect->height = max_y - min_y + 1; } else { rect->width = 0; rect->height = 0; } } /** * Copies data from the given buffer to the surface at the given coordinates. * The dimensions and location of the destination rectangle will be altered * to remove as many unchanged pixels as possible. * * @param src_buffer The buffer to copy. * @param src_stride The number of bytes in each row of the source buffer. * @param sx The X coordinate of the source rectangle. * @param sy The Y coordinate of the source rectangle. * @param dst The destination surface. * @param rect The destination rectangle. * @param opaque Non-zero if the source surface is opaque (its alpha channel * should be ignored), zero otherwise. */ static void __guac_common_surface_put(unsigned char* src_buffer, int src_stride, int* sx, int* sy, guac_common_surface* dst, guac_common_rect* rect, int opaque) { unsigned char* dst_buffer = dst->buffer; int dst_stride = dst->stride; int x, y; int min_x = rect->width; int min_y = rect->height; int max_x = 0; int max_y = 0; int orig_x = rect->x; int orig_y = rect->y; src_buffer += src_stride * (*sy) + 4 * (*sx); dst_buffer += (dst_stride * rect->y) + (4 * rect->x); /* For each row */ for (y=0; y < rect->height; y++) { uint32_t* src_current = (uint32_t*) src_buffer; uint32_t* dst_current = (uint32_t*) dst_buffer; /* Copy row */ for (x=0; x < rect->width; x++) { if (opaque || (*src_current & 0xFF000000)) { uint32_t new_color = *src_current | 0xFF000000; uint32_t old_color = *dst_current; if (old_color != new_color) { if (x < min_x) min_x = x; if (y < min_y) min_y = y; if (x > max_x) max_x = x; if (y > max_y) max_y = y; *dst_current = new_color; } } src_current++; dst_current++; } /* Next row */ src_buffer += src_stride; dst_buffer += dst_stride; } /* Restrict destination rect to only updated pixels */ if (max_x >= min_x && max_y >= min_y) { rect->x += min_x; rect->y += min_y; rect->width = max_x - min_x + 1; rect->height = max_y - min_y + 1; } else { rect->width = 0; rect->height = 0; } /* Update source X/Y */ *sx += rect->x - orig_x; *sy += rect->y - orig_y; } /** * Fills the given surface with color, using the given buffer as a mask. Color * will be added to the given surface iff the corresponding pixel within the * buffer is opaque. * * @param src_buffer The buffer to use as a mask. * @param src_stride The number of bytes in each row of the source buffer. * @param sx The X coordinate of the source rectangle. * @param sy The Y coordinate of the source rectangle. * @param dst The destination surface. * @param rect The destination rectangle. * @param red The red component of the color of the fill. * @param green The green component of the color of the fill. * @param blue The blue component of the color of the fill. */ static void __guac_common_surface_fill_mask(unsigned char* src_buffer, int src_stride, int sx, int sy, guac_common_surface* dst, guac_common_rect* rect, int red, int green, int blue) { unsigned char* dst_buffer = dst->buffer; int dst_stride = dst->stride; uint32_t color = 0xFF000000 | (red << 16) | (green << 8) | blue; int x, y; src_buffer += src_stride*sy + 4*sx; dst_buffer += (dst_stride * rect->y) + (4 * rect->x); /* For each row */ for (y=0; y < rect->height; y++) { uint32_t* src_current = (uint32_t*) src_buffer; uint32_t* dst_current = (uint32_t*) dst_buffer; /* Stencil row */ for (x=0; x < rect->width; x++) { /* Fill with color if opaque */ if (*src_current & 0xFF000000) *dst_current = color; src_current++; dst_current++; } /* Next row */ src_buffer += src_stride; dst_buffer += dst_stride; } } /** * Copies data from the given surface to the given destination surface using * the specified transfer function. * * @param src_buffer The buffer to copy. * @param src_stride The number of bytes in each row of the source buffer. * @param sx The X coordinate of the source rectangle. * @param sy The Y coordinate of the source rectangle. * @param op The transfer function to use. * @param dst The destination surface. * @param rect The destination rectangle. */ static void __guac_common_surface_transfer(guac_common_surface* src, int* sx, int* sy, guac_transfer_function op, guac_common_surface* dst, guac_common_rect* rect) { unsigned char* src_buffer = src->buffer; unsigned char* dst_buffer = dst->buffer; int x, y; int src_stride, dst_stride; int step = 1; int min_x = rect->width - 1; int min_y = rect->height - 1; int max_x = 0; int max_y = 0; int orig_x = rect->x; int orig_y = rect->y; /* Copy forwards only if destination is in a different surface or is before source */ if (src != dst || rect->y < *sy || (rect->y == *sy && rect->x < *sx)) { src_buffer += src->stride * (*sy) + 4 * (*sx); dst_buffer += (dst->stride * rect->y) + (4 * rect->x); src_stride = src->stride; dst_stride = dst->stride; step = 1; } /* Otherwise, copy backwards */ else { src_buffer += src->stride * (*sy + rect->height - 1) + 4 * (*sx + rect->width - 1); dst_buffer += dst->stride * (rect->y + rect->height - 1) + 4 * (rect->x + rect->width - 1); src_stride = -src->stride; dst_stride = -dst->stride; step = -1; } /* For each row */ for (y=0; y < rect->height; y++) { uint32_t* src_current = (uint32_t*) src_buffer; uint32_t* dst_current = (uint32_t*) dst_buffer; /* Transfer each pixel in row */ for (x=0; x < rect->width; x++) { if (__guac_common_surface_transfer_int(op, src_current, dst_current)) { if (x < min_x) min_x = x; if (y < min_y) min_y = y; if (x > max_x) max_x = x; if (y > max_y) max_y = y; } src_current += step; dst_current += step; } /* Next row */ src_buffer += src_stride; dst_buffer += dst_stride; } /* Translate X coordinate space of moving backwards */ if (step < 0) { int old_max_x = max_x; max_x = rect->width - 1 - min_x; min_x = rect->width - 1 - old_max_x; } /* Translate Y coordinate space of moving backwards */ if (dst_stride < 0) { int old_max_y = max_y; max_y = rect->height - 1 - min_y; min_y = rect->height - 1 - old_max_y; } /* Restrict destination rect to only updated pixels */ if (max_x >= min_x && max_y >= min_y) { rect->x += min_x; rect->y += min_y; rect->width = max_x - min_x + 1; rect->height = max_y - min_y + 1; } else { rect->width = 0; rect->height = 0; } /* Update source X/Y */ *sx += rect->x - orig_x; *sy += rect->y - orig_y; } guac_common_surface* guac_common_surface_alloc(guac_client* client, guac_socket* socket, const guac_layer* layer, int w, int h) { /* Calculate heat map dimensions */ int heat_width = GUAC_COMMON_SURFACE_HEAT_DIMENSION(w); int heat_height = GUAC_COMMON_SURFACE_HEAT_DIMENSION(h); /* Init surface */ guac_common_surface* surface = calloc(1, sizeof(guac_common_surface)); surface->client = client; surface->socket = socket; surface->layer = layer; surface->parent = GUAC_DEFAULT_LAYER; surface->width = w; surface->height = h; pthread_mutex_init(&surface->_lock, NULL); /* Create corresponding Cairo surface */ surface->stride = cairo_format_stride_for_width(CAIRO_FORMAT_ARGB32, w); surface->buffer = calloc(h, surface->stride); /* Create corresponding heat map */ surface->heat_map = calloc(heat_width * heat_height, sizeof(guac_common_surface_heat_cell)); /* Reset clipping rect */ guac_common_surface_reset_clip(surface); /* Layers must initially exist */ if (layer->index >= 0) { guac_protocol_send_size(socket, layer, w, h); surface->realized = 1; } /* Defer creation of buffers */ else surface->realized = 0; return surface; } void guac_common_surface_free(guac_common_surface* surface) { /* Only dispose of surface if it exists */ if (surface->realized) guac_protocol_send_dispose(surface->socket, surface->layer); pthread_mutex_destroy(&surface->_lock); free(surface->heat_map); free(surface->buffer); free(surface); } void guac_common_surface_resize(guac_common_surface* surface, int w, int h) { pthread_mutex_lock(&surface->_lock); /* Ignore if resize will have no effect */ if (w == surface->width && h == surface->height) goto complete; guac_socket* socket = surface->socket; const guac_layer* layer = surface->layer; unsigned char* old_buffer; int old_stride; guac_common_rect old_rect; int sx = 0; int sy = 0; /* Calculate heat map dimensions */ int heat_width = GUAC_COMMON_SURFACE_HEAT_DIMENSION(w); int heat_height = GUAC_COMMON_SURFACE_HEAT_DIMENSION(h); /* Copy old surface data */ old_buffer = surface->buffer; old_stride = surface->stride; guac_common_rect_init(&old_rect, 0, 0, surface->width, surface->height); /* Re-initialize at new size */ surface->width = w; surface->height = h; surface->stride = cairo_format_stride_for_width(CAIRO_FORMAT_ARGB32, w); surface->buffer = calloc(h, surface->stride); __guac_common_bound_rect(surface, &surface->clip_rect, NULL, NULL); /* Copy relevant old data */ __guac_common_bound_rect(surface, &old_rect, NULL, NULL); __guac_common_surface_put(old_buffer, old_stride, &sx, &sy, surface, &old_rect, 1); /* Free old data */ free(old_buffer); /* Allocate completely new heat map (can safely discard old stats) */ free(surface->heat_map); surface->heat_map = calloc(heat_width * heat_height, sizeof(guac_common_surface_heat_cell)); /* Resize dirty rect to fit new surface dimensions */ if (surface->dirty) { __guac_common_bound_rect(surface, &surface->dirty_rect, NULL, NULL); if (surface->dirty_rect.width <= 0 || surface->dirty_rect.height <= 0) surface->dirty = 0; } /* Update Guacamole layer */ if (surface->realized) guac_protocol_send_size(socket, layer, w, h); complete: pthread_mutex_unlock(&surface->_lock); } void guac_common_surface_draw(guac_common_surface* surface, int x, int y, cairo_surface_t* src) { pthread_mutex_lock(&surface->_lock); unsigned char* buffer = cairo_image_surface_get_data(src); cairo_format_t format = cairo_image_surface_get_format(src); int stride = cairo_image_surface_get_stride(src); int w = cairo_image_surface_get_width(src); int h = cairo_image_surface_get_height(src); int sx = 0; int sy = 0; guac_common_rect rect; guac_common_rect_init(&rect, x, y, w, h); /* Clip operation */ __guac_common_clip_rect(surface, &rect, &sx, &sy); if (rect.width <= 0 || rect.height <= 0) goto complete; /* Update backing surface */ __guac_common_surface_put(buffer, stride, &sx, &sy, surface, &rect, format != CAIRO_FORMAT_ARGB32); if (rect.width <= 0 || rect.height <= 0) goto complete; /* Update the heat map for the update rectangle. */ guac_timestamp time = guac_timestamp_current(); __guac_common_surface_touch_rect(surface, &rect, time); /* Flush if not combining */ if (!__guac_common_should_combine(surface, &rect, 0)) __guac_common_surface_flush_deferred(surface); /* Always defer draws */ __guac_common_mark_dirty(surface, &rect); complete: pthread_mutex_unlock(&surface->_lock); } void guac_common_surface_paint(guac_common_surface* surface, int x, int y, cairo_surface_t* src, int red, int green, int blue) { pthread_mutex_lock(&surface->_lock); unsigned char* buffer = cairo_image_surface_get_data(src); int stride = cairo_image_surface_get_stride(src); int w = cairo_image_surface_get_width(src); int h = cairo_image_surface_get_height(src); int sx = 0; int sy = 0; guac_common_rect rect; guac_common_rect_init(&rect, x, y, w, h); /* Clip operation */ __guac_common_clip_rect(surface, &rect, &sx, &sy); if (rect.width <= 0 || rect.height <= 0) goto complete; /* Update backing surface */ __guac_common_surface_fill_mask(buffer, stride, sx, sy, surface, &rect, red, green, blue); /* Flush if not combining */ if (!__guac_common_should_combine(surface, &rect, 0)) __guac_common_surface_flush_deferred(surface); /* Always defer draws */ __guac_common_mark_dirty(surface, &rect); complete: pthread_mutex_unlock(&surface->_lock); } void guac_common_surface_copy(guac_common_surface* src, int sx, int sy, int w, int h, guac_common_surface* dst, int dx, int dy) { /* Lock both surfaces */ pthread_mutex_lock(&dst->_lock); if (src != dst) pthread_mutex_lock(&src->_lock); guac_socket* socket = dst->socket; const guac_layer* src_layer = src->layer; const guac_layer* dst_layer = dst->layer; guac_common_rect srect; guac_common_rect_init(&srect, sx, sy, w, h); /* Clip operation source rect to bounds */ __guac_common_bound_rect(src, &srect, &dx, &dy); if (srect.width <= 0 || srect.height <= 0) goto complete; guac_common_rect drect; guac_common_rect_init(&drect, dx, dy, srect.width, srect.height); /* Clip operation destination rect */ __guac_common_clip_rect(dst, &drect, &srect.x, &srect.y); if (drect.width <= 0 || drect.height <= 0) goto complete; /* NOTE: Being the last rectangle to be adjusted, only the width/height of * drect is now correct! */ /* Update backing surface first only if drect cannot intersect srect */ if (src != dst) { __guac_common_surface_transfer(src, &srect.x, &srect.y, GUAC_TRANSFER_BINARY_SRC, dst, &drect); if (drect.width <= 0 || drect.height <= 0) goto complete; } /* Defer if combining */ if (__guac_common_should_combine(dst, &drect, 1)) __guac_common_mark_dirty(dst, &drect); /* Otherwise, flush and draw immediately */ else { __guac_common_surface_flush(dst); __guac_common_surface_flush(src); guac_protocol_send_copy(socket, src_layer, srect.x, srect.y, drect.width, drect.height, GUAC_COMP_OVER, dst_layer, drect.x, drect.y); dst->realized = 1; } /* Update backing surface last if drect can intersect srect */ if (src == dst) __guac_common_surface_transfer(src, &srect.x, &srect.y, GUAC_TRANSFER_BINARY_SRC, dst, &drect); complete: /* Unlock both surfaces */ pthread_mutex_unlock(&dst->_lock); if (src != dst) pthread_mutex_unlock(&src->_lock); } void guac_common_surface_transfer(guac_common_surface* src, int sx, int sy, int w, int h, guac_transfer_function op, guac_common_surface* dst, int dx, int dy) { /* Lock both surfaces */ pthread_mutex_lock(&dst->_lock); if (src != dst) pthread_mutex_lock(&src->_lock); guac_socket* socket = dst->socket; const guac_layer* src_layer = src->layer; const guac_layer* dst_layer = dst->layer; guac_common_rect srect; guac_common_rect_init(&srect, sx, sy, w, h); /* Clip operation source rect to bounds */ __guac_common_bound_rect(src, &srect, &dx, &dy); if (srect.width <= 0 || srect.height <= 0) goto complete; guac_common_rect drect; guac_common_rect_init(&drect, dx, dy, srect.width, srect.height); /* Clip operation destination rect */ __guac_common_clip_rect(dst, &drect, &srect.x, &srect.y); if (drect.width <= 0 || drect.height <= 0) goto complete; /* NOTE: Being the last rectangle to be adjusted, only the width/height of * drect is now correct! */ /* Update backing surface first only if drect cannot intersect srect */ if (src != dst) { __guac_common_surface_transfer(src, &srect.x, &srect.y, op, dst, &drect); if (drect.width <= 0 || drect.height <= 0) goto complete; } /* Defer if combining */ if (__guac_common_should_combine(dst, &drect, 1)) __guac_common_mark_dirty(dst, &drect); /* Otherwise, flush and draw immediately */ else { __guac_common_surface_flush(dst); __guac_common_surface_flush(src); guac_protocol_send_transfer(socket, src_layer, srect.x, srect.y, drect.width, drect.height, op, dst_layer, drect.x, drect.y); dst->realized = 1; } /* Update backing surface last if drect can intersect srect */ if (src == dst) __guac_common_surface_transfer(src, &srect.x, &srect.y, op, dst, &drect); complete: /* Unlock both surfaces */ pthread_mutex_unlock(&dst->_lock); if (src != dst) pthread_mutex_unlock(&src->_lock); } void guac_common_surface_set(guac_common_surface* surface, int x, int y, int w, int h, int red, int green, int blue, int alpha) { pthread_mutex_lock(&surface->_lock); guac_socket* socket = surface->socket; const guac_layer* layer = surface->layer; guac_common_rect rect; guac_common_rect_init(&rect, x, y, w, h); /* Clip operation */ __guac_common_clip_rect(surface, &rect, NULL, NULL); if (rect.width <= 0 || rect.height <= 0) goto complete; /* Update backing surface */ __guac_common_surface_set(surface, &rect, red, green, blue, alpha); if (rect.width <= 0 || rect.height <= 0) goto complete; /* Handle as normal draw if non-opaque */ if (alpha != 0xFF) { /* Flush if not combining */ if (!__guac_common_should_combine(surface, &rect, 0)) __guac_common_surface_flush_deferred(surface); /* Always defer draws */ __guac_common_mark_dirty(surface, &rect); } /* Defer if combining */ else if (__guac_common_should_combine(surface, &rect, 1)) __guac_common_mark_dirty(surface, &rect); /* Otherwise, flush and draw immediately */ else { __guac_common_surface_flush(surface); guac_protocol_send_rect(socket, layer, rect.x, rect.y, rect.width, rect.height); guac_protocol_send_cfill(socket, GUAC_COMP_OVER, layer, red, green, blue, alpha); surface->realized = 1; } complete: pthread_mutex_unlock(&surface->_lock); } void guac_common_surface_clip(guac_common_surface* surface, int x, int y, int w, int h) { pthread_mutex_lock(&surface->_lock); guac_common_rect clip; /* Init clipping rectangle if clipping not already applied */ if (!surface->clipped) { guac_common_rect_init(&surface->clip_rect, 0, 0, surface->width, surface->height); surface->clipped = 1; } guac_common_rect_init(&clip, x, y, w, h); guac_common_rect_constrain(&surface->clip_rect, &clip); pthread_mutex_unlock(&surface->_lock); } void guac_common_surface_reset_clip(guac_common_surface* surface) { pthread_mutex_lock(&surface->_lock); surface->clipped = 0; pthread_mutex_unlock(&surface->_lock); } /** * Flushes the bitmap update currently described by the dirty rectangle within * the given surface directly via an "img" instruction as PNG data. The * resulting instructions will be sent over the socket associated with the * given surface. * * @param surface * The surface to flush. * * @param opaque * Whether the rectangle being flushed contains only fully-opaque pixels. */ static void __guac_common_surface_flush_to_png(guac_common_surface* surface, int opaque) { if (surface->dirty) { guac_socket* socket = surface->socket; const guac_layer* layer = surface->layer; /* Get Cairo surface for specified rect */ unsigned char* buffer = surface->buffer + surface->dirty_rect.y * surface->stride + surface->dirty_rect.x * 4; cairo_surface_t* rect; /* Use RGB24 if the image is fully opaque */ if (opaque) rect = cairo_image_surface_create_for_data(buffer, CAIRO_FORMAT_RGB24, surface->dirty_rect.width, surface->dirty_rect.height, surface->stride); /* Otherwise ARGB32 is needed */ else { rect = cairo_image_surface_create_for_data(buffer, CAIRO_FORMAT_ARGB32, surface->dirty_rect.width, surface->dirty_rect.height, surface->stride); /* Clear destination rect first */ guac_protocol_send_rect(socket, layer, surface->dirty_rect.x, surface->dirty_rect.y, surface->dirty_rect.width, surface->dirty_rect.height); guac_protocol_send_cfill(socket, GUAC_COMP_ROUT, layer, 0x00, 0x00, 0x00, 0xFF); } /* Send PNG for rect */ guac_client_stream_png(surface->client, socket, GUAC_COMP_OVER, layer, surface->dirty_rect.x, surface->dirty_rect.y, rect); cairo_surface_destroy(rect); surface->realized = 1; /* Surface is no longer dirty */ surface->dirty = 0; } } /** * Flushes the bitmap update currently described by the dirty rectangle within * the given surface directly via an "img" instruction as JPEG data. The * resulting instructions will be sent over the socket associated with the * given surface. * * @param surface * The surface to flush. */ static void __guac_common_surface_flush_to_jpeg(guac_common_surface* surface) { if (surface->dirty) { guac_socket* socket = surface->socket; const guac_layer* layer = surface->layer; guac_common_rect max; guac_common_rect_init(&max, 0, 0, surface->width, surface->height); /* Expand the dirty rect size to fit in a grid with cells equal to the * minimum JPEG block size */ guac_common_rect_expand_to_grid(GUAC_SURFACE_JPEG_BLOCK_SIZE, &surface->dirty_rect, &max); /* Get Cairo surface for specified rect */ unsigned char* buffer = surface->buffer + surface->dirty_rect.y * surface->stride + surface->dirty_rect.x * 4; cairo_surface_t* rect = cairo_image_surface_create_for_data(buffer, CAIRO_FORMAT_RGB24, surface->dirty_rect.width, surface->dirty_rect.height, surface->stride); /* Send JPEG for rect */ guac_client_stream_jpeg(surface->client, socket, GUAC_COMP_OVER, layer, surface->dirty_rect.x, surface->dirty_rect.y, rect, GUAC_SURFACE_JPEG_IMAGE_QUALITY); cairo_surface_destroy(rect); surface->realized = 1; /* Surface is no longer dirty */ surface->dirty = 0; } } /** * Flushes the bitmap update currently described by the dirty rectangle within * the given surface directly via an "img" instruction as WebP data. The * resulting instructions will be sent over the socket associated with the * given surface. * * @param surface * The surface to flush. * * @param opaque * Whether the rectangle being flushed contains only fully-opaque pixels. */ static void __guac_common_surface_flush_to_webp(guac_common_surface* surface, int opaque) { if (surface->dirty) { guac_socket* socket = surface->socket; const guac_layer* layer = surface->layer; guac_common_rect max; guac_common_rect_init(&max, 0, 0, surface->width, surface->height); /* Expand the dirty rect size to fit in a grid with cells equal to the * minimum WebP block size */ guac_common_rect_expand_to_grid(GUAC_SURFACE_WEBP_BLOCK_SIZE, &surface->dirty_rect, &max); /* Get Cairo surface for specified rect */ unsigned char* buffer = surface->buffer + surface->dirty_rect.y * surface->stride + surface->dirty_rect.x * 4; cairo_surface_t* rect; /* Use RGB24 if the image is fully opaque */ if (opaque) rect = cairo_image_surface_create_for_data(buffer, CAIRO_FORMAT_RGB24, surface->dirty_rect.width, surface->dirty_rect.height, surface->stride); /* Otherwise ARGB32 is needed */ else rect = cairo_image_surface_create_for_data(buffer, CAIRO_FORMAT_ARGB32, surface->dirty_rect.width, surface->dirty_rect.height, surface->stride); /* Send WebP for rect */ guac_client_stream_webp(surface->client, socket, GUAC_COMP_OVER, layer, surface->dirty_rect.x, surface->dirty_rect.y, rect, GUAC_SURFACE_WEBP_IMAGE_QUALITY, 0); cairo_surface_destroy(rect); surface->realized = 1; /* Surface is no longer dirty */ surface->dirty = 0; } } /** * Comparator for instances of guac_common_surface_bitmap_rect, the elements * which make up a surface's bitmap buffer. * * @see qsort */ static int __guac_common_surface_bitmap_rect_compare(const void* a, const void* b) { guac_common_surface_bitmap_rect* ra = (guac_common_surface_bitmap_rect*) a; guac_common_surface_bitmap_rect* rb = (guac_common_surface_bitmap_rect*) b; /* Order roughly top to bottom, left to right */ if (ra->rect.y != rb->rect.y) return ra->rect.y - rb->rect.y; if (ra->rect.x != rb->rect.x) return ra->rect.x - rb->rect.x; /* Wider updates should come first (more likely to intersect later) */ if (ra->rect.width != rb->rect.width) return rb->rect.width - ra->rect.width; /* Shorter updates should come first (less likely to increase cost) */ return ra->rect.height - rb->rect.height; } /** * Flushes only the properties of the given surface, such as layer location or * opacity. Image state is not flushed. If the surface represents a buffer or * the default layer, this function has no effect. * * @param surface * The surface to flush. */ static void __guac_common_surface_flush_properties( guac_common_surface* surface) { guac_socket* socket = surface->socket; /* Only applicable to non-default visible layers */ if (surface->layer->index <= 0) return; /* Flush opacity */ if (surface->opacity_dirty) { guac_protocol_send_shade(socket, surface->layer, surface->opacity); surface->opacity_dirty = 0; } /* Flush location and hierarchy */ if (surface->location_dirty) { guac_protocol_send_move(socket, surface->layer, surface->parent, surface->x, surface->y, surface->z); surface->location_dirty = 0; } } static void __guac_common_surface_flush(guac_common_surface* surface) { /* Flush final dirty rectangle to queue. */ __guac_common_surface_flush_to_queue(surface); guac_common_surface_bitmap_rect* current = surface->bitmap_queue; int i, j; int original_queue_length; int flushed = 0; original_queue_length = surface->bitmap_queue_length; /* Sort updates to make combination less costly */ qsort(surface->bitmap_queue, surface->bitmap_queue_length, sizeof(guac_common_surface_bitmap_rect), __guac_common_surface_bitmap_rect_compare); /* Flush all rects in queue */ for (i=0; i < surface->bitmap_queue_length; i++) { /* Get next unflushed candidate */ guac_common_surface_bitmap_rect* candidate = current; if (!candidate->flushed) { int combined = 0; /* Build up rect as much as possible */ for (j=i; j < surface->bitmap_queue_length; j++) { if (!candidate->flushed) { /* Clip candidate within current bounds */ __guac_common_bound_rect(surface, &candidate->rect, NULL, NULL); if (candidate->rect.width <= 0 || candidate->rect.height <= 0) candidate->flushed = 1; /* Combine if reasonable */ else if (__guac_common_should_combine(surface, &candidate->rect, 0) || !surface->dirty) { __guac_common_mark_dirty(surface, &candidate->rect); candidate->flushed = 1; combined++; } } candidate++; } /* Re-add to queue if there's room and this update was modified or we expect others might be */ if ((combined > 1 || i < original_queue_length) && surface->bitmap_queue_length < GUAC_COMMON_SURFACE_QUEUE_SIZE) __guac_common_surface_flush_to_queue(surface); /* Flush as bitmap otherwise */ else if (surface->dirty) { flushed++; int opaque = __guac_common_surface_is_opaque(surface, &surface->dirty_rect); /* Prefer WebP when reasonable */ if (__guac_common_surface_should_use_webp(surface, &surface->dirty_rect)) __guac_common_surface_flush_to_webp(surface, opaque); /* If not WebP, JPEG is the next best (lossy) choice */ else if (opaque && __guac_common_surface_should_use_jpeg( surface, &surface->dirty_rect)) __guac_common_surface_flush_to_jpeg(surface); /* Use PNG if no lossy formats are appropriate */ else __guac_common_surface_flush_to_png(surface, opaque); } } current++; } /* Flush complete */ surface->bitmap_queue_length = 0; } void guac_common_surface_flush(guac_common_surface* surface) { pthread_mutex_lock(&surface->_lock); /* Flush any applicable layer properties */ __guac_common_surface_flush_properties(surface); /* Flush surface contents */ __guac_common_surface_flush(surface); pthread_mutex_unlock(&surface->_lock); } void guac_common_surface_dup(guac_common_surface* surface, guac_user* user, guac_socket* socket) { pthread_mutex_lock(&surface->_lock); /* Do nothing if not realized */ if (!surface->realized) goto complete; /* Synchronize layer-specific properties if applicable */ if (surface->layer->index > 0) { /* Synchronize opacity */ guac_protocol_send_shade(socket, surface->layer, surface->opacity); /* Synchronize location and hierarchy */ guac_protocol_send_move(socket, surface->layer, surface->parent, surface->x, surface->y, surface->z); } /* Sync size to new socket */ guac_protocol_send_size(socket, surface->layer, surface->width, surface->height); /* Send contents of layer, if non-empty */ if (surface->width > 0 && surface->height > 0) { /* Get entire surface */ cairo_surface_t* rect = cairo_image_surface_create_for_data( surface->buffer, CAIRO_FORMAT_ARGB32, surface->width, surface->height, surface->stride); /* Send PNG for rect */ guac_user_stream_png(user, socket, GUAC_COMP_OVER, surface->layer, 0, 0, rect); cairo_surface_destroy(rect); } complete: pthread_mutex_unlock(&surface->_lock); }