/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Copyright (C) 2010 Intel Corporation.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
* Author:
* Emmanuele Bassi <ebassi@linux.intel.com>
*
* Based on the MxDeformTexture class, written by:
* Chris Lord <chris@linux.intel.com>
*/
/**
* SECTION:clutter-deform-effect
* @Title: ClutterDeformEffect
* @Short_Description: A base class for effects deforming the geometry
* of an actor
*
* #ClutterDeformEffect is an abstract class providing all the plumbing
* for creating effects that result in the deformation of an actor's
* geometry.
*
* #ClutterDeformEffect uses offscreen buffers to render the contents of
* a #ClutterActor and then the Cogl vertex buffers API to submit the
* geometry to the GPU.
*
* <refsect2>
* <title>Implementing ClutterDeformEffect</title>
* <para>Sub-classes of #ClutterDeformEffect should override the
* #ClutterDeformEffectClass.deform_vertex() virtual function; this function
* is called on every vertex that needs to be deformed by the effect.
* Each passed vertex is an in-out parameter that initially contains the
* position of the vertex and should be modified according to a specific
* deformation algorithm.</para>
* </refsect2>
*
* #ClutterDeformEffect is available since Clutter 1.4
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#define CLUTTER_ENABLE_EXPERIMENTAL_API
#include "clutter-deform-effect.h"
#include <cogl/cogl.h>
#include "clutter-debug.h"
#include "clutter-enum-types.h"
#include "clutter-offscreen-effect-private.h"
#include "clutter-private.h"
#define DEFAULT_N_TILES 32
struct _ClutterDeformEffectPrivate
{
CoglPipeline *back_pipeline;
gint x_tiles;
gint y_tiles;
CoglAttributeBuffer *buffer;
CoglPrimitive *primitive;
CoglPrimitive *lines_primitive;
gint n_vertices;
gulong allocation_id;
guint is_dirty : 1;
};
enum
{
PROP_0,
PROP_X_TILES,
PROP_Y_TILES,
PROP_BACK_MATERIAL,
PROP_LAST
};
static GParamSpec *obj_props[PROP_LAST];
G_DEFINE_ABSTRACT_TYPE (ClutterDeformEffect,
clutter_deform_effect,
CLUTTER_TYPE_OFFSCREEN_EFFECT);
static void
clutter_deform_effect_real_deform_vertex (ClutterDeformEffect *effect,
gfloat width,
gfloat height,
CoglTextureVertex *vertex)
{
g_warning ("%s: Deformation effect of type '%s' does not implement "
"the required ClutterDeformEffect::deform_vertex virtual "
"function.",
G_STRLOC,
G_OBJECT_TYPE_NAME (effect));
}
static void
clutter_deform_effect_deform_vertex (ClutterDeformEffect *effect,
gfloat width,
gfloat height,
CoglTextureVertex *vertex)
{
CLUTTER_DEFORM_EFFECT_GET_CLASS (effect)->deform_vertex (effect,
width, height,
vertex);
}
static void
vbo_invalidate (ClutterActor *actor,
const ClutterActorBox *allocation,
ClutterAllocationFlags flags,
ClutterDeformEffect *effect)
{
effect->priv->is_dirty = TRUE;
}
static void
clutter_deform_effect_set_actor (ClutterActorMeta *meta,
ClutterActor *actor)
{
ClutterDeformEffectPrivate *priv = CLUTTER_DEFORM_EFFECT (meta)->priv;
if (priv->allocation_id != 0)
{
ClutterActor *old_actor = clutter_actor_meta_get_actor (meta);
if (old_actor != NULL)
g_signal_handler_disconnect (old_actor, priv->allocation_id);
priv->allocation_id = 0;
}
/* we need to invalidate the VBO whenever the allocation of the actor
* changes
*/
if (actor != NULL)
priv->allocation_id = g_signal_connect (actor, "allocation-changed",
G_CALLBACK (vbo_invalidate),
meta);
priv->is_dirty = TRUE;
CLUTTER_ACTOR_META_CLASS (clutter_deform_effect_parent_class)->set_actor (meta, actor);
}
static void
clutter_deform_effect_paint_target (ClutterOffscreenEffect *effect)
{
ClutterDeformEffect *self= CLUTTER_DEFORM_EFFECT (effect);
ClutterDeformEffectPrivate *priv = self->priv;
CoglHandle material;
CoglPipeline *pipeline;
CoglDepthState depth_state;
CoglFramebuffer *fb = cogl_get_draw_framebuffer ();
if (priv->is_dirty)
{
gboolean mapped_buffer;
CoglVertexP3T2C4 *verts;
ClutterActor *actor;
gfloat width, height;
guint opacity;
gint i, j;
actor = clutter_actor_meta_get_actor (CLUTTER_ACTOR_META (effect));
opacity = clutter_actor_get_paint_opacity (actor);
/* if we don't have a target size, fall back to the actor's
* allocation, though wrong it might be
*/
if (!clutter_offscreen_effect_get_target_size (effect, &width, &height))
clutter_actor_get_size (actor, &width, &height);
/* XXX ideally, the sub-classes should tell us what they
* changed in the texture vertices; we then would be able to
* avoid resubmitting the same data, if it did not change. for
* the time being, we resubmit everything
*/
verts = cogl_buffer_map (COGL_BUFFER (priv->buffer),
COGL_BUFFER_ACCESS_WRITE,
COGL_BUFFER_MAP_HINT_DISCARD);
/* If the map failed then we'll resort to allocating a temporary
buffer */
if (verts == NULL)
{
mapped_buffer = FALSE;
verts = g_malloc (sizeof (*verts) * priv->n_vertices);
}
else
mapped_buffer = TRUE;
for (i = 0; i < priv->y_tiles + 1; i++)
{
for (j = 0; j < priv->x_tiles + 1; j++)
{
CoglVertexP3T2C4 *vertex_out;
CoglTextureVertex vertex;
/* CoglTextureVertex isn't an ideal structure to use for
this because it contains a CoglColor. The internal
layout of CoglColor is mean to be private so Clutter
can not pass a pointer to it as a vertex
attribute. Also it contains padding so we end up
storing more data in the vertex buffer than we need
to. Instead we let the application modify a dummy
vertex and then copy the details back out to a more
well-defined struct */
vertex.tx = (float) j / priv->x_tiles;
vertex.ty = (float) i / priv->y_tiles;
vertex.x = width * vertex.tx;
vertex.y = height * vertex.ty;
vertex.z = 0.0f;
cogl_color_init_from_4ub (&vertex.color, 255, 255, 255, opacity);
clutter_deform_effect_deform_vertex (self,
width, height,
&vertex);
vertex_out = verts + i * (priv->x_tiles + 1) + j;
vertex_out->x = vertex.x;
vertex_out->y = vertex.y;
vertex_out->z = vertex.z;
vertex_out->s = vertex.tx;
vertex_out->t = vertex.ty;
vertex_out->r = cogl_color_get_red_byte (&vertex.color);
vertex_out->g = cogl_color_get_green_byte (&vertex.color);
vertex_out->b = cogl_color_get_blue_byte (&vertex.color);
vertex_out->a = cogl_color_get_alpha_byte (&vertex.color);
}
}
if (mapped_buffer)
cogl_buffer_unmap (COGL_BUFFER (priv->buffer));
else
{
cogl_buffer_set_data (COGL_BUFFER (priv->buffer),
0, /* offset */
verts,
sizeof (*verts) * priv->n_vertices);
g_free (verts);
}
priv->is_dirty = FALSE;
}
material = clutter_offscreen_effect_get_target (effect);
pipeline = COGL_PIPELINE (material);
/* enable depth testing */
cogl_depth_state_init (&depth_state);
cogl_depth_state_set_test_enabled (&depth_state, TRUE);
cogl_pipeline_set_depth_state (pipeline, &depth_state, NULL);
/* enable backface culling if we have a back material */
if (priv->back_pipeline != NULL)
cogl_pipeline_set_cull_face_mode (pipeline,
COGL_PIPELINE_CULL_FACE_MODE_BACK);
/* draw the front */
if (material != NULL)
cogl_framebuffer_draw_primitive (fb, pipeline, priv->primitive);
/* draw the back */
if (priv->back_pipeline != NULL)
{
CoglPipeline *back_pipeline;
/* We probably shouldn't be modifying the user's material so
instead we make a temporary copy */
back_pipeline = cogl_pipeline_copy (priv->back_pipeline);
cogl_pipeline_set_depth_state (back_pipeline, &depth_state, NULL);
cogl_pipeline_set_cull_face_mode (pipeline,
COGL_PIPELINE_CULL_FACE_MODE_FRONT);
cogl_framebuffer_draw_primitive (fb, back_pipeline, priv->primitive);
cogl_object_unref (back_pipeline);
}
if (G_UNLIKELY (priv->lines_primitive != NULL))
{
CoglContext *ctx =
clutter_backend_get_cogl_context (clutter_get_default_backend ());
CoglPipeline *lines_pipeline = cogl_pipeline_new (ctx);
cogl_pipeline_set_color4f (lines_pipeline, 1.0, 0, 0, 1.0);
cogl_framebuffer_draw_primitive (fb, lines_pipeline,
priv->lines_primitive);
cogl_object_unref (lines_pipeline);
}
}
static inline void
clutter_deform_effect_free_arrays (ClutterDeformEffect *self)
{
ClutterDeformEffectPrivate *priv = self->priv;
if (priv->buffer)
{
cogl_object_unref (priv->buffer);
priv->buffer = NULL;
}
if (priv->primitive)
{
cogl_object_unref (priv->primitive);
priv->primitive = NULL;
}
if (priv->lines_primitive)
{
cogl_object_unref (priv->lines_primitive);
priv->lines_primitive = NULL;
}
}
static void
clutter_deform_effect_init_arrays (ClutterDeformEffect *self)
{
ClutterDeformEffectPrivate *priv = self->priv;
gint x, y, direction, n_indices;
CoglAttribute *attributes[3];
guint16 *static_indices;
CoglContext *ctx =
clutter_backend_get_cogl_context (clutter_get_default_backend ());
CoglIndices *indices;
guint16 *idx;
int i;
clutter_deform_effect_free_arrays (self);
n_indices = ((2 + 2 * priv->x_tiles)
* priv->y_tiles
+ (priv->y_tiles - 1));
static_indices = g_new (guint16, n_indices);
#define MESH_INDEX(x,y) ((y) * (priv->x_tiles + 1) + (x))
/* compute all the triangles from the various tiles */
direction = 1;
idx = static_indices;
idx[0] = MESH_INDEX (0, 0);
idx[1] = MESH_INDEX (0, 1);
idx += 2;
for (y = 0; y < priv->y_tiles; y++)
{
for (x = 0; x < priv->x_tiles; x++)
{
if (direction)
{
idx[0] = MESH_INDEX (x + 1, y);
idx[1] = MESH_INDEX (x + 1, y + 1);
}
else
{
idx[0] = MESH_INDEX (priv->x_tiles - x - 1, y);
idx[1] = MESH_INDEX (priv->x_tiles - x - 1, y + 1);
}
idx += 2;
}
if (y == (priv->y_tiles - 1))
break;
if (direction)
{
idx[0] = MESH_INDEX (priv->x_tiles, y + 1);
idx[1] = MESH_INDEX (priv->x_tiles, y + 1);
idx[2] = MESH_INDEX (priv->x_tiles, y + 2);
}
else
{
idx[0] = MESH_INDEX (0, y + 1);
idx[1] = MESH_INDEX (0, y + 1);
idx[2] = MESH_INDEX (0, y + 2);
}
idx += 3;
direction = !direction;
}
#undef MESH_INDEX
indices = cogl_indices_new (ctx,
COGL_INDICES_TYPE_UNSIGNED_SHORT,
static_indices,
n_indices);
g_free (static_indices);
priv->n_vertices = (priv->x_tiles + 1) * (priv->y_tiles + 1);
priv->buffer =
cogl_attribute_buffer_new (ctx,
sizeof (CoglVertexP3T2C4) *
priv->n_vertices,
NULL);
/* The application is expected to continuously modify the vertices
so we should give a hint to Cogl about that */
cogl_buffer_set_update_hint (COGL_BUFFER (priv->buffer),
COGL_BUFFER_UPDATE_HINT_DYNAMIC);
attributes[0] = cogl_attribute_new (priv->buffer,
"cogl_position_in",
sizeof (CoglVertexP3T2C4),
G_STRUCT_OFFSET (CoglVertexP3T2C4, x),
3, /* n_components */
COGL_ATTRIBUTE_TYPE_FLOAT);
attributes[1] = cogl_attribute_new (priv->buffer,
"cogl_tex_coord0_in",
sizeof (CoglVertexP3T2C4),
G_STRUCT_OFFSET (CoglVertexP3T2C4, s),
2, /* n_components */
COGL_ATTRIBUTE_TYPE_FLOAT);
attributes[2] = cogl_attribute_new (priv->buffer,
"cogl_color_in",
sizeof (CoglVertexP3T2C4),
G_STRUCT_OFFSET (CoglVertexP3T2C4, r),
4, /* n_components */
COGL_ATTRIBUTE_TYPE_UNSIGNED_BYTE);
priv->primitive =
cogl_primitive_new_with_attributes (COGL_VERTICES_MODE_TRIANGLE_STRIP,
priv->n_vertices,
attributes,
3 /* n_attributes */);
cogl_primitive_set_indices (priv->primitive,
indices,
n_indices);
if (G_UNLIKELY (clutter_paint_debug_flags & CLUTTER_DEBUG_PAINT_DEFORM_TILES))
{
priv->lines_primitive =
cogl_primitive_new_with_attributes (COGL_VERTICES_MODE_LINE_STRIP,
priv->n_vertices,
attributes,
2 /* n_attributes */);
cogl_primitive_set_indices (priv->lines_primitive,
indices,
n_indices);
}
cogl_object_unref (indices);
for (i = 0; i < 3; i++)
cogl_object_unref (attributes[i]);
priv->is_dirty = TRUE;
}
static inline void
clutter_deform_effect_free_back_pipeline (ClutterDeformEffect *self)
{
ClutterDeformEffectPrivate *priv = self->priv;
if (priv->back_pipeline != NULL)
{
cogl_object_unref (priv->back_pipeline);
priv->back_pipeline = NULL;
}
}
static void
clutter_deform_effect_finalize (GObject *gobject)
{
ClutterDeformEffect *self = CLUTTER_DEFORM_EFFECT (gobject);
clutter_deform_effect_free_arrays (self);
clutter_deform_effect_free_back_pipeline (self);
G_OBJECT_CLASS (clutter_deform_effect_parent_class)->finalize (gobject);
}
static void
clutter_deform_effect_set_property (GObject *gobject,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
ClutterDeformEffect *self = CLUTTER_DEFORM_EFFECT (gobject);
switch (prop_id)
{
case PROP_X_TILES:
clutter_deform_effect_set_n_tiles (self, g_value_get_uint (value),
self->priv->y_tiles);
break;
case PROP_Y_TILES:
clutter_deform_effect_set_n_tiles (self, self->priv->x_tiles,
g_value_get_uint (value));
break;
case PROP_BACK_MATERIAL:
clutter_deform_effect_set_back_material (self, g_value_get_boxed (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_deform_effect_get_property (GObject *gobject,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
ClutterDeformEffectPrivate *priv = CLUTTER_DEFORM_EFFECT (gobject)->priv;
switch (prop_id)
{
case PROP_X_TILES:
g_value_set_uint (value, priv->x_tiles);
break;
case PROP_Y_TILES:
g_value_set_uint (value, priv->y_tiles);
break;
case PROP_BACK_MATERIAL:
g_value_set_boxed (value, priv->back_pipeline);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_deform_effect_class_init (ClutterDeformEffectClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
ClutterActorMetaClass *meta_class = CLUTTER_ACTOR_META_CLASS (klass);
ClutterOffscreenEffectClass *offscreen_class = CLUTTER_OFFSCREEN_EFFECT_CLASS (klass);
g_type_class_add_private (klass, sizeof (ClutterDeformEffectPrivate));
klass->deform_vertex = clutter_deform_effect_real_deform_vertex;
/**
* ClutterDeformEffect:x-tiles:
*
* The number of horizontal tiles. The bigger the number, the
* smaller the tiles
*
* Since: 1.4
*/
obj_props[PROP_X_TILES] =
g_param_spec_uint ("x-tiles",
P_("Horizontal Tiles"),
P_("The number of horizontal tiles"),
1, G_MAXUINT,
DEFAULT_N_TILES,
CLUTTER_PARAM_READWRITE);
/**
* ClutterDeformEffect:y-tiles:
*
* The number of vertical tiles. The bigger the number, the
* smaller the tiles
*
* Since: 1.4
*/
obj_props[PROP_Y_TILES] =
g_param_spec_uint ("y-tiles",
P_("Vertical Tiles"),
P_("The number of vertical tiles"),
1, G_MAXUINT,
DEFAULT_N_TILES,
CLUTTER_PARAM_READWRITE);
/**
* ClutterDeformEffect:back-material:
*
* A material to be used when painting the back of the actor
* to which this effect has been applied
*
* By default, no material will be used
*
* Since: 1.4
*/
obj_props[PROP_BACK_MATERIAL] =
g_param_spec_boxed ("back-material",
P_("Back Material"),
P_("The material to be used when painting the back of the actor"),
COGL_TYPE_HANDLE,
CLUTTER_PARAM_READWRITE);
gobject_class->finalize = clutter_deform_effect_finalize;
gobject_class->set_property = clutter_deform_effect_set_property;
gobject_class->get_property = clutter_deform_effect_get_property;
g_object_class_install_properties (gobject_class,
PROP_LAST,
obj_props);
meta_class->set_actor = clutter_deform_effect_set_actor;
offscreen_class->paint_target = clutter_deform_effect_paint_target;
}
static void
clutter_deform_effect_init (ClutterDeformEffect *self)
{
self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self, CLUTTER_TYPE_DEFORM_EFFECT,
ClutterDeformEffectPrivate);
self->priv->x_tiles = self->priv->y_tiles = DEFAULT_N_TILES;
self->priv->back_pipeline = NULL;
clutter_deform_effect_init_arrays (self);
}
/**
* clutter_deform_effect_set_back_material:
* @effect: a #ClutterDeformEffect
* @material: (allow-none): a handle to a Cogl material
*
* Sets the material that should be used when drawing the back face
* of the actor during a deformation
*
* The #ClutterDeformEffect will take a reference on the material's
* handle
*
* Since: 1.4
*/
void
clutter_deform_effect_set_back_material (ClutterDeformEffect *effect,
CoglHandle material)
{
ClutterDeformEffectPrivate *priv;
CoglPipeline *pipeline = COGL_PIPELINE (material);
g_return_if_fail (CLUTTER_IS_DEFORM_EFFECT (effect));
g_return_if_fail (pipeline == NULL || cogl_is_pipeline (pipeline));
priv = effect->priv;
clutter_deform_effect_free_back_pipeline (effect);
priv->back_pipeline = material;
if (priv->back_pipeline != NULL)
cogl_object_ref (priv->back_pipeline);
clutter_deform_effect_invalidate (effect);
}
/**
* clutter_deform_effect_get_back_material:
* @effect: a #ClutterDeformEffect
*
* Retrieves the handle to the back face material used by @effect
*
* Return value: (transfer none): a handle for the material, or %NULL.
* The returned material is owned by the #ClutterDeformEffect and it
* should not be freed directly
*
* Since: 1.4
*/
CoglHandle
clutter_deform_effect_get_back_material (ClutterDeformEffect *effect)
{
g_return_val_if_fail (CLUTTER_IS_DEFORM_EFFECT (effect), NULL);
return effect->priv->back_pipeline;
}
/**
* clutter_deform_effect_set_n_tiles:
* @effect: a #ClutterDeformEffect
* @x_tiles: number of horizontal tiles
* @y_tiles: number of vertical tiles
*
* Sets the number of horizontal and vertical tiles to be used
* when applying the effect
*
* More tiles allow a finer grained deformation at the expenses
* of computation
*
* Since: 1.4
*/
void
clutter_deform_effect_set_n_tiles (ClutterDeformEffect *effect,
guint x_tiles,
guint y_tiles)
{
ClutterDeformEffectPrivate *priv;
gboolean tiles_changed = FALSE;
g_return_if_fail (CLUTTER_IS_DEFORM_EFFECT (effect));
g_return_if_fail (x_tiles > 0 && y_tiles > 0);
priv = effect->priv;
g_object_freeze_notify (G_OBJECT (effect));
if (priv->x_tiles != x_tiles)
{
priv->x_tiles = x_tiles;
g_object_notify_by_pspec (G_OBJECT (effect), obj_props[PROP_X_TILES]);
tiles_changed = TRUE;
}
if (priv->y_tiles != y_tiles)
{
priv->y_tiles = y_tiles;
g_object_notify_by_pspec (G_OBJECT (effect), obj_props[PROP_Y_TILES]);
tiles_changed = TRUE;
}
if (tiles_changed)
{
clutter_deform_effect_init_arrays (effect);
clutter_deform_effect_invalidate (effect);
}
g_object_thaw_notify (G_OBJECT (effect));
}
/**
* clutter_deform_effect_get_n_tiles:
* @effect: a #ClutterDeformEffect
* @x_tiles: (out): return location for the number of horizontal tiles,
* or %NULL
* @y_tiles: (out): return location for the number of vertical tiles,
* or %NULL
*
* Retrieves the number of horizontal and vertical tiles used to sub-divide
* the actor's geometry during the effect
*
* Since: 1.4
*/
void
clutter_deform_effect_get_n_tiles (ClutterDeformEffect *effect,
guint *x_tiles,
guint *y_tiles)
{
g_return_if_fail (CLUTTER_IS_DEFORM_EFFECT (effect));
if (x_tiles != NULL)
*x_tiles = effect->priv->x_tiles;
if (y_tiles != NULL)
*y_tiles = effect->priv->y_tiles;
}
/**
* clutter_deform_effect_invalidate:
* @effect: a #ClutterDeformEffect
*
* Invalidates the @effect<!-- -->'s vertices and, if it is associated
* to an actor, it will queue a redraw
*
* Since: 1.4
*/
void
clutter_deform_effect_invalidate (ClutterDeformEffect *effect)
{
ClutterActor *actor;
g_return_if_fail (CLUTTER_IS_DEFORM_EFFECT (effect));
if (effect->priv->is_dirty)
return;
effect->priv->is_dirty = TRUE;
actor = clutter_actor_meta_get_actor (CLUTTER_ACTOR_META (effect));
if (actor != NULL)
clutter_effect_queue_repaint (CLUTTER_EFFECT (effect));
}