compositor: transform surface coordinates if a surface scaler is used

Implements wl_surface_scaler.set by setting desired
src_{x,y,width,height} and dst_{width,height} values in the
weston_buffer_viewport struct, then altering coordinates in
weston_surface_to_buffer* functions if there is a scaler set for said
surface.

diff --git a/src/compositor.c b/src/compositor.c
index 8a6ff38..5169921 100644 (file)
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -475,10 +475,13 @@ weston_surface_create(struct weston_compositor *compositor)
 
        surface->buffer_viewport.transform = WL_OUTPUT_TRANSFORM_NORMAL;
        surface->buffer_viewport.scale = 1;
+       surface->buffer_viewport.scaler_set = 0;
        surface->pending.buffer_viewport = surface->buffer_viewport;
        surface->output = NULL;
        surface->pending.newly_attached = 0;
 
+       surface->surface_scaler_resource = NULL;
+
        pixman_region32_init(&surface->damage);
        pixman_region32_init(&surface->opaque);
        region_init_infinite(&surface->input);
@@ -705,15 +708,38 @@ weston_transformed_region(int width, int height,
        free(dest_rects);
 }
 
+static void
+scaler_surface_to_buffer(struct weston_surface *surface,
+                        float sx, float sy, float *bx, float *by)
+{
+       if (surface->buffer_viewport.scaler_set) {
+               double a, b;
+
+               a = sx / surface->buffer_viewport.dst_width;
+               b = a * wl_fixed_to_double(surface->buffer_viewport.src_width);
+               *bx = b + wl_fixed_to_double(surface->buffer_viewport.src_x);
+
+               a = sy / surface->buffer_viewport.dst_height;
+               b = a * wl_fixed_to_double(surface->buffer_viewport.src_height);
+               *by = b + wl_fixed_to_double(surface->buffer_viewport.src_y);
+       } else {
+               *bx = sx;
+               *by = sy;
+       }
+}
+
 WL_EXPORT void
 weston_surface_to_buffer_float(struct weston_surface *surface,
                               float sx, float sy, float *bx, float *by)
 {
+       /* first transform coordinates if the scaler is set */
+       scaler_surface_to_buffer(surface, sx, sy, bx, by);
+
        weston_transformed_coord(surface->width,
                                 surface->height,
                                 surface->buffer_viewport.transform,
                                 surface->buffer_viewport.scale,
-                                sx, sy, bx, by);
+                                *bx, *by, bx, by);
 }
 
 WL_EXPORT void
@@ -722,11 +748,9 @@ weston_surface_to_buffer(struct weston_surface *surface,
 {
        float bxf, byf;
 
-       weston_transformed_coord(surface->width,
-                                surface->height,
-                                surface->buffer_viewport.transform,
-                                surface->buffer_viewport.scale,
-                                sx, sy, &bxf, &byf);
+       weston_surface_to_buffer_float(surface,
+                                      sx, sy, &bxf, &byf);
+
        *bx = floorf(bxf);
        *by = floorf(byf);
 }
@@ -735,6 +759,17 @@ WL_EXPORT pixman_box32_t
 weston_surface_to_buffer_rect(struct weston_surface *surface,
                              pixman_box32_t rect)
 {
+       float xf, yf;
+
+       /* first transform box coordinates if the scaler is set */
+       scaler_surface_to_buffer(surface, rect.x1, rect.y1, &xf, &yf);
+       rect.x1 = floorf(xf);
+       rect.y1 = floorf(yf);
+
+       scaler_surface_to_buffer(surface, rect.x2, rect.y2, &xf, &yf);
+       rect.x2 = floorf(xf);
+       rect.y2 = floorf(yf);
+
        return weston_transformed_rect(surface->width,
                                       surface->height,
                                       surface->buffer_viewport.transform,
@@ -1252,6 +1287,12 @@ weston_surface_set_size_from_buffer(struct weston_surface *surface)
                return;
        }
 
+       if (surface->buffer_viewport.scaler_set) {
+               surface->width = surface->buffer_viewport.dst_width;
+               surface->height = surface->buffer_viewport.dst_height;
+               return;
+       }
+
        switch (surface->buffer_viewport.transform) {
        case WL_OUTPUT_TRANSFORM_90:
        case WL_OUTPUT_TRANSFORM_270:
@@ -2054,6 +2095,7 @@ weston_surface_commit(struct weston_surface *surface)
 
        /* wl_surface.set_buffer_transform */
        /* wl_surface.set_buffer_scale */
+       /* wl_surface_scaler.set */
        surface->buffer_viewport = surface->pending.buffer_viewport;
 
        /* wl_surface.attach */
@@ -2279,6 +2321,7 @@ weston_subsurface_commit_from_cache(struct weston_subsurface *sub)
 
        /* wl_surface.set_buffer_transform */
        /* wl_surface.set_buffer_scale */
+       /* wl_surface_scaler.set */
        surface->buffer_viewport = sub->cached.buffer_viewport;
 
        /* wl_surface.attach */
@@ -3405,6 +3448,11 @@ weston_output_transform_coordinate(struct weston_output *output,
 static void
 destroy_surface_scaler(struct wl_resource *resource)
 {
+       struct weston_surface *surface =
+               wl_resource_get_user_data(resource);
+
+       surface->surface_scaler_resource = NULL;
+       surface->pending.buffer_viewport.scaler_set = 0;
 }
 
 static void
@@ -3424,6 +3472,11 @@ surface_scaler_set(struct wl_client *client,
                   int32_t dst_width,
                   int32_t dst_height)
 {
+       struct weston_surface *surface =
+               wl_resource_get_user_data(resource);
+
+       assert(surface->surface_scaler_resource != NULL);
+
        if (wl_fixed_to_double(src_width) < 0 ||
            wl_fixed_to_double(src_height) < 0) {
                wl_resource_post_error(resource,
@@ -3442,7 +3495,14 @@ surface_scaler_set(struct wl_client *client,
                return;
        }
 
-       /* TODO */
+       surface->pending.buffer_viewport.scaler_set = 1;
+
+       surface->pending.buffer_viewport.src_x = src_x;
+       surface->pending.buffer_viewport.src_y = src_y;
+       surface->pending.buffer_viewport.src_width = src_width;
+       surface->pending.buffer_viewport.src_height = src_height;
+       surface->pending.buffer_viewport.dst_width = dst_width;
+       surface->pending.buffer_viewport.dst_height = dst_height;
 }
 
 static const struct wl_surface_scaler_interface surface_scaler_interface = {
@@ -3466,7 +3526,13 @@ scaler_get_surface_scaler(struct wl_client *client,
        struct weston_surface *surface = wl_resource_get_user_data(surface_resource);
        struct wl_resource *resource;
 
-       /* TODO: check we don't already have one for this surface */
+       if (surface->surface_scaler_resource) {
+               wl_resource_post_error(scaler,
+                       WL_SCALER_ERROR_SCALER_EXISTS,
+                       "a surface scaler for that surface already exists");
+               return;
+       }
+
        resource = wl_resource_create(client, &wl_surface_scaler_interface,
                                      1, id);
        if (resource == NULL) {
@@ -3476,6 +3542,8 @@ scaler_get_surface_scaler(struct wl_client *client,
 
        wl_resource_set_implementation(resource, &surface_scaler_interface,
                                       surface, destroy_surface_scaler);
+
+       surface->surface_scaler_resource = resource;
 }
 
 static const struct wl_scaler_interface scaler_interface = {

diff --git a/src/compositor.h b/src/compositor.h
index f32a497..2b9bb6e 100644 (file)
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -658,6 +658,15 @@ struct weston_buffer_viewport {
 
        /* wl_surface.set_scaling_factor */
        int32_t scale;
+
+       /* bool for whether wl_surface_scaler.set has been
+        * called yet (before this is called there is no
+        * cropping or scaling on the surface) */
+       int scaler_set; /* bool */
+
+       wl_fixed_t src_x, src_y;
+       wl_fixed_t src_width, src_height;
+       int32_t dst_width, dst_height;
 };
 
 struct weston_region {
@@ -851,6 +860,9 @@ struct weston_surface {
        struct weston_buffer_viewport buffer_viewport;
        int keep_buffer; /* bool for backends to prevent early release */
 
+       /* wl_surface_scaler resource for this surface */
+       struct wl_resource *surface_scaler_resource;
+
        /* All the pending state, that wl_surface.commit will apply. */
        struct {
                /* wl_surface.attach */
@@ -874,6 +886,7 @@ struct weston_surface {
 
                /* wl_surface.set_buffer_transform */
                /* wl_surface.set_scaling_factor */
+               /* wl_surface_scaler.set */
                struct weston_buffer_viewport buffer_viewport;
        } pending;