/**************************************************************************
 *
 * Copyright 2009 Younes Manton.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 **************************************************************************/

#include <assert.h>

#include <pipe/p_compiler.h>
#include <pipe/p_context.h>

#include <util/u_memory.h>
#include <util/u_draw.h>
#include <util/u_surface.h>

#include <tgsi/tgsi_ureg.h>

#include "vl_csc.h"
#include "vl_types.h"
#include "vl_compositor.h"

typedef float csc_matrix[16];

static void *
create_vert_shader(struct vl_compositor *c)
{
   struct ureg_program *shader;
   struct ureg_src vpos, vtex;
   struct ureg_dst o_vpos, o_vtex;

   shader = ureg_create(TGSI_PROCESSOR_VERTEX);
   if (!shader)
      return false;

   vpos = ureg_DECL_vs_input(shader, 0);
   vtex = ureg_DECL_vs_input(shader, 1);
   o_vpos = ureg_DECL_output(shader, TGSI_SEMANTIC_POSITION, 0);
   o_vtex = ureg_DECL_output(shader, TGSI_SEMANTIC_GENERIC, 1);

   /*
    * o_vpos = vpos
    * o_vtex = vtex
    */
   ureg_MOV(shader, o_vpos, vpos);
   ureg_MOV(shader, o_vtex, vtex);

   ureg_END(shader);

   return ureg_create_shader_and_destroy(shader, c->pipe);
}

static void *
create_frag_shader_video_buffer(struct vl_compositor *c)
{
   struct ureg_program *shader;
   struct ureg_src tc;
   struct ureg_src csc[3];
   struct ureg_src sampler[3];
   struct ureg_dst texel;
   struct ureg_dst fragment;
   unsigned i;

   shader = ureg_create(TGSI_PROCESSOR_FRAGMENT);
   if (!shader)
      return false;

   tc = ureg_DECL_fs_input(shader, TGSI_SEMANTIC_GENERIC, 1, TGSI_INTERPOLATE_LINEAR);
   for (i = 0; i < 3; ++i) {
      csc[i] = ureg_DECL_constant(shader, i);
      sampler[i] = ureg_DECL_sampler(shader, i);
   }
   texel = ureg_DECL_temporary(shader);
   fragment = ureg_DECL_output(shader, TGSI_SEMANTIC_COLOR, 0);

   /*
    * texel.xyz = tex(tc, sampler[i])
    * fragment = csc * texel
    */
   for (i = 0; i < 3; ++i)
      ureg_TEX(shader, ureg_writemask(texel, TGSI_WRITEMASK_X << i), TGSI_TEXTURE_2D, tc, sampler[i]);

   ureg_MOV(shader, ureg_writemask(texel, TGSI_WRITEMASK_W), ureg_imm1f(shader, 1.0f));

   for (i = 0; i < 3; ++i)
      ureg_DP4(shader, ureg_writemask(fragment, TGSI_WRITEMASK_X << i), csc[i], ureg_src(texel));

   ureg_MOV(shader, ureg_writemask(fragment, TGSI_WRITEMASK_W), ureg_imm1f(shader, 1.0f));

   ureg_release_temporary(shader, texel);
   ureg_END(shader);

   return ureg_create_shader_and_destroy(shader, c->pipe);
}

static void *
create_frag_shader_palette(struct vl_compositor *c)
{
   struct ureg_program *shader;
   struct ureg_src csc[3];
   struct ureg_src tc;
   struct ureg_src sampler;
   struct ureg_src palette;
   struct ureg_dst texel;
   struct ureg_dst fragment;
   unsigned i;

   shader = ureg_create(TGSI_PROCESSOR_FRAGMENT);
   if (!shader)
      return false;

   for (i = 0; i < 3; ++i)
      csc[i] = ureg_DECL_constant(shader, i);

   tc = ureg_DECL_fs_input(shader, TGSI_SEMANTIC_GENERIC, 1, TGSI_INTERPOLATE_LINEAR);
   sampler = ureg_DECL_sampler(shader, 0);
   palette = ureg_DECL_sampler(shader, 1);
   texel = ureg_DECL_temporary(shader);
   fragment = ureg_DECL_output(shader, TGSI_SEMANTIC_COLOR, 0);

   /*
    * texel = tex(tc, sampler)
    * fragment.xyz = tex(texel, palette) * csc
    * fragment.a = texel.a
    */
   ureg_TEX(shader, texel, TGSI_TEXTURE_2D, tc, sampler);
   ureg_MUL(shader, ureg_writemask(texel, TGSI_WRITEMASK_X), ureg_src(texel), ureg_imm1f(shader, 15.0f / 16.0f));
   ureg_MOV(shader, ureg_writemask(fragment, TGSI_WRITEMASK_W), ureg_src(texel));

   ureg_TEX(shader, texel, TGSI_TEXTURE_1D, ureg_src(texel), palette);

   for (i = 0; i < 3; ++i)
      ureg_DP4(shader, ureg_writemask(fragment, TGSI_WRITEMASK_X << i), csc[i], ureg_src(texel));

   ureg_release_temporary(shader, texel);
   ureg_END(shader);

   return ureg_create_shader_and_destroy(shader, c->pipe);
}

static void *
create_frag_shader_rgba(struct vl_compositor *c)
{
   struct ureg_program *shader;
   struct ureg_src tc;
   struct ureg_src sampler;
   struct ureg_dst fragment;

   shader = ureg_create(TGSI_PROCESSOR_FRAGMENT);
   if (!shader)
      return false;

   tc = ureg_DECL_fs_input(shader, TGSI_SEMANTIC_GENERIC, 1, TGSI_INTERPOLATE_LINEAR);
   sampler = ureg_DECL_sampler(shader, 0);
   fragment = ureg_DECL_output(shader, TGSI_SEMANTIC_COLOR, 0);

   /*
    * fragment = tex(tc, sampler)
    */
   ureg_TEX(shader, fragment, TGSI_TEXTURE_2D, tc, sampler);
   ureg_END(shader);

   return ureg_create_shader_and_destroy(shader, c->pipe);
}

static bool
init_shaders(struct vl_compositor *c)
{
   assert(c);

   c->vs = create_vert_shader(c);
   if (!c->vs) {
      debug_printf("Unable to create vertex shader.\n");
      return false;
   }

   c->fs_video_buffer = create_frag_shader_video_buffer(c);
   if (!c->fs_video_buffer) {
      debug_printf("Unable to create YCbCr-to-RGB fragment shader.\n");
      return false;
   }

   c->fs_palette = create_frag_shader_palette(c);
   if (!c->fs_palette) {
      debug_printf("Unable to create Palette-to-RGB fragment shader.\n");
      return false;
   }

   c->fs_rgba = create_frag_shader_rgba(c);
   if (!c->fs_rgba) {
      debug_printf("Unable to create RGB-to-RGB fragment shader.\n");
      return false;
   }

   return true;
}

static void cleanup_shaders(struct vl_compositor *c)
{
   assert(c);

   c->pipe->delete_vs_state(c->pipe, c->vs);
   c->pipe->delete_fs_state(c->pipe, c->fs_video_buffer);
   c->pipe->delete_fs_state(c->pipe, c->fs_palette);
   c->pipe->delete_fs_state(c->pipe, c->fs_rgba);
}

static bool
init_pipe_state(struct vl_compositor *c)
{
   struct pipe_rasterizer_state rast;
   struct pipe_sampler_state sampler;
   struct pipe_blend_state blend;
   struct pipe_depth_stencil_alpha_state dsa;
   unsigned i;

   assert(c);

   c->fb_state.nr_cbufs = 1;
   c->fb_state.zsbuf = NULL;

   c->viewport.scale[2] = 1;
   c->viewport.scale[3] = 1;
   c->viewport.translate[2] = 0;
   c->viewport.translate[3] = 0;

   memset(&sampler, 0, sizeof(sampler));
   sampler.wrap_s = PIPE_TEX_WRAP_CLAMP_TO_EDGE;
   sampler.wrap_t = PIPE_TEX_WRAP_CLAMP_TO_EDGE;
   sampler.wrap_r = PIPE_TEX_WRAP_CLAMP_TO_EDGE;
   sampler.min_img_filter = PIPE_TEX_FILTER_LINEAR;
   sampler.min_mip_filter = PIPE_TEX_MIPFILTER_NONE;
   sampler.mag_img_filter = PIPE_TEX_FILTER_LINEAR;
   sampler.compare_mode = PIPE_TEX_COMPARE_NONE;
   sampler.compare_func = PIPE_FUNC_ALWAYS;
   sampler.normalized_coords = 1;

   c->sampler_linear = c->pipe->create_sampler_state(c->pipe, &sampler);

   sampler.min_img_filter = PIPE_TEX_FILTER_NEAREST;
   sampler.mag_img_filter = PIPE_TEX_FILTER_NEAREST;
   c->sampler_nearest = c->pipe->create_sampler_state(c->pipe, &sampler);

   memset(&blend, 0, sizeof blend);
   blend.independent_blend_enable = 0;
   blend.rt[0].blend_enable = 1;
   blend.rt[0].rgb_func = PIPE_BLEND_ADD;
   blend.rt[0].rgb_src_factor = PIPE_BLENDFACTOR_SRC_ALPHA;
   blend.rt[0].rgb_dst_factor = PIPE_BLENDFACTOR_INV_SRC_ALPHA;
   blend.rt[0].alpha_func = PIPE_BLEND_ADD;
   blend.rt[0].alpha_src_factor = PIPE_BLENDFACTOR_ONE;
   blend.rt[0].alpha_dst_factor = PIPE_BLENDFACTOR_ONE;
   blend.logicop_enable = 0;
   blend.logicop_func = PIPE_LOGICOP_CLEAR;
   blend.rt[0].colormask = PIPE_MASK_RGBA;
   blend.dither = 0;
   c->blend = c->pipe->create_blend_state(c->pipe, &blend);

   memset(&rast, 0, sizeof rast);
   rast.flatshade = 1;
   rast.front_ccw = 1;
   rast.cull_face = PIPE_FACE_NONE;
   rast.fill_back = PIPE_POLYGON_MODE_FILL;
   rast.fill_front = PIPE_POLYGON_MODE_FILL;
   rast.scissor = 1;
   rast.line_width = 1;
   rast.point_size_per_vertex = 1;
   rast.offset_units = 1;
   rast.offset_scale = 1;
   rast.gl_rasterization_rules = 1;

   c->rast = c->pipe->create_rasterizer_state(c->pipe, &rast);

   memset(&dsa, 0, sizeof dsa);
   dsa.depth.enabled = 0;
   dsa.depth.writemask = 0;
   dsa.depth.func = PIPE_FUNC_ALWAYS;
   for (i = 0; i < 2; ++i) {
      dsa.stencil[i].enabled = 0;
      dsa.stencil[i].func = PIPE_FUNC_ALWAYS;
      dsa.stencil[i].fail_op = PIPE_STENCIL_OP_KEEP;
      dsa.stencil[i].zpass_op = PIPE_STENCIL_OP_KEEP;
      dsa.stencil[i].zfail_op = PIPE_STENCIL_OP_KEEP;
      dsa.stencil[i].valuemask = 0;
      dsa.stencil[i].writemask = 0;
   }
   dsa.alpha.enabled = 0;
   dsa.alpha.func = PIPE_FUNC_ALWAYS;
   dsa.alpha.ref_value = 0;
   c->dsa = c->pipe->create_depth_stencil_alpha_state(c->pipe, &dsa);
   c->pipe->bind_depth_stencil_alpha_state(c->pipe, c->dsa);
   return true;
}

static void cleanup_pipe_state(struct vl_compositor *c)
{
   assert(c);

   /* Asserted in softpipe_delete_fs_state() for some reason */
   c->pipe->bind_vs_state(c->pipe, NULL);
   c->pipe->bind_fs_state(c->pipe, NULL);

   c->pipe->delete_depth_stencil_alpha_state(c->pipe, c->dsa);
   c->pipe->delete_sampler_state(c->pipe, c->sampler_linear);
   c->pipe->delete_sampler_state(c->pipe, c->sampler_nearest);
   c->pipe->delete_blend_state(c->pipe, c->blend);
   c->pipe->delete_rasterizer_state(c->pipe, c->rast);
}

static bool
create_vertex_buffer(struct vl_compositor *c)
{
   assert(c);

   pipe_resource_reference(&c->vertex_buf.buffer, NULL);
   c->vertex_buf.buffer = pipe_buffer_create
   (
      c->pipe->screen,
      PIPE_BIND_VERTEX_BUFFER,
      PIPE_USAGE_STREAM,
      sizeof(struct vertex4f) * VL_COMPOSITOR_MAX_LAYERS * 4
   );
   return c->vertex_buf.buffer != NULL;
}

static bool
init_buffers(struct vl_compositor *c)
{
   struct pipe_vertex_element vertex_elems[2];

   assert(c);

   /*
    * Create our vertex buffer and vertex buffer elements
    */
   c->vertex_buf.stride = sizeof(struct vertex4f);
   c->vertex_buf.buffer_offset = 0;
   create_vertex_buffer(c);

   vertex_elems[0].src_offset = 0;
   vertex_elems[0].instance_divisor = 0;
   vertex_elems[0].vertex_buffer_index = 0;
   vertex_elems[0].src_format = PIPE_FORMAT_R32G32_FLOAT;
   vertex_elems[1].src_offset = sizeof(struct vertex2f);
   vertex_elems[1].instance_divisor = 0;
   vertex_elems[1].vertex_buffer_index = 0;
   vertex_elems[1].src_format = PIPE_FORMAT_R32G32_FLOAT;
   c->vertex_elems_state = c->pipe->create_vertex_elements_state(c->pipe, 2, vertex_elems);

   /*
    * Create our fragment shader's constant buffer
    * Const buffer contains the color conversion matrix and bias vectors
    */
   /* XXX: Create with IMMUTABLE/STATIC... although it does change every once in a long while... */
   c->csc_matrix = pipe_buffer_create
   (
      c->pipe->screen,
      PIPE_BIND_CONSTANT_BUFFER,
      PIPE_USAGE_STATIC,
      sizeof(csc_matrix)
   );

   return true;
}

static void
cleanup_buffers(struct vl_compositor *c)
{
   assert(c);

   c->pipe->delete_vertex_elements_state(c->pipe, c->vertex_elems_state);
   pipe_resource_reference(&c->vertex_buf.buffer, NULL);
   pipe_resource_reference(&c->csc_matrix, NULL);
}

static INLINE struct pipe_video_rect
default_rect(struct vl_compositor_layer *layer)
{
   struct pipe_resource *res = layer->sampler_views[0]->texture;
   struct pipe_video_rect rect = { 0, 0, res->width0, res->height0 };
   return rect;
}

static INLINE struct vertex2f
calc_topleft(struct vertex2f size, struct pipe_video_rect rect)
{
   struct vertex2f res = { rect.x / size.x, rect.y / size.y };
   return res;
}

static INLINE struct vertex2f
calc_bottomright(struct vertex2f size, struct pipe_video_rect rect)
{
   struct vertex2f res = { (rect.x + rect.w) / size.x, (rect.y + rect.h) / size.y };
   return res;
}

static INLINE void
calc_src_and_dst(struct vl_compositor_layer *layer, unsigned width, unsigned height,
                 struct pipe_video_rect src, struct pipe_video_rect dst)
{
   struct vertex2f size =  { width, height };

   layer->src.tl = calc_topleft(size, src);
   layer->src.br = calc_bottomright(size, src);
   layer->dst.tl = calc_topleft(size, dst);
   layer->dst.br = calc_bottomright(size, dst);
}

static void
gen_rect_verts(struct vertex4f *vb, struct vl_compositor_layer *layer)
{
   assert(vb && layer);

   vb[0].x = layer->dst.tl.x;
   vb[0].y = layer->dst.tl.y;
   vb[0].z = layer->src.tl.x;
   vb[0].w = layer->src.tl.y;

   vb[1].x = layer->dst.br.x;
   vb[1].y = layer->dst.tl.y;
   vb[1].z = layer->src.br.x;
   vb[1].w = layer->src.tl.y;

   vb[2].x = layer->dst.br.x;
   vb[2].y = layer->dst.br.y;
   vb[2].z = layer->src.br.x;
   vb[2].w = layer->src.br.y;

   vb[3].x = layer->dst.tl.x;
   vb[3].y = layer->dst.br.y;
   vb[3].z = layer->src.tl.x;
   vb[3].w = layer->src.br.y;
}

static void
gen_vertex_data(struct vl_compositor *c)
{
   struct vertex4f *vb;
   struct pipe_transfer *buf_transfer;
   unsigned i;

   assert(c);

   vb = pipe_buffer_map(c->pipe, c->vertex_buf.buffer,
                        PIPE_TRANSFER_WRITE | PIPE_TRANSFER_DISCARD | PIPE_TRANSFER_DONTBLOCK,
                        &buf_transfer);

   if (!vb) {
      // If buffer is still locked from last draw create a new one
      create_vertex_buffer(c);
      vb = pipe_buffer_map(c->pipe, c->vertex_buf.buffer,
                           PIPE_TRANSFER_WRITE | PIPE_TRANSFER_DISCARD,
                           &buf_transfer);
   }

   for (i = 0; i < VL_COMPOSITOR_MAX_LAYERS; i++) {
      if (c->used_layers & (1 << i)) {
         struct vl_compositor_layer *layer = &c->layers[i];
         gen_rect_verts(vb, layer);
         vb += 4;

         if (layer->clearing &&
             c->dirty_tl.x >= layer->dst.tl.x &&
             c->dirty_tl.y >= layer->dst.tl.y &&
             c->dirty_br.x <= layer->dst.br.x &&
             c->dirty_br.y <= layer->dst.br.y) {

            // We clear the dirty area anyway, no need for clear_render_target
            c->dirty_tl.x = c->dirty_tl.y = 1.0f;
            c->dirty_br.x = c->dirty_br.y = 0.0f;
         }
      }
   }

   pipe_buffer_unmap(c->pipe, buf_transfer);
}

static void
draw_layers(struct vl_compositor *c)
{
   unsigned vb_index, i;

   assert(c);

   for (i = 0, vb_index = 0; i < VL_COMPOSITOR_MAX_LAYERS; ++i) {
      if (c->used_layers & (1 << i)) {
         struct vl_compositor_layer *layer = &c->layers[i];
         struct pipe_sampler_view **samplers = &layer->sampler_views[0];
         unsigned num_sampler_views = !samplers[1] ? 1 : !samplers[2] ? 2 : 3;

         c->pipe->bind_fs_state(c->pipe, layer->fs);
         c->pipe->bind_fragment_sampler_states(c->pipe, num_sampler_views, layer->samplers);
         c->pipe->set_fragment_sampler_views(c->pipe, num_sampler_views, samplers);
         util_draw_arrays(c->pipe, PIPE_PRIM_QUADS, vb_index * 4, 4);
         vb_index++;

         // Remember the currently drawn area as dirty for the next draw command
         c->dirty_tl.x = MIN2(layer->dst.tl.x, c->dirty_tl.x);
         c->dirty_tl.y = MIN2(layer->dst.tl.y, c->dirty_tl.y);
         c->dirty_br.x = MAX2(layer->dst.br.x, c->dirty_br.x);
         c->dirty_br.y = MAX2(layer->dst.br.y, c->dirty_br.y);
      }
   }
}

void
vl_compositor_reset_dirty_area(struct vl_compositor *c)
{
   assert(c);

   c->dirty_tl.x = c->dirty_tl.y = 0.0f;
   c->dirty_br.x = c->dirty_br.y = 1.0f;
}

void
vl_compositor_set_clear_color(struct vl_compositor *c, float color[4])
{
   unsigned i;

   assert(c);

   for (i = 0; i < 4; ++i)
      c->clear_color[i] = color[i];
}

void
vl_compositor_clear_layers(struct vl_compositor *c)
{
   unsigned i, j;

   assert(c);

   c->used_layers = 0;
   for ( i = 0; i < VL_COMPOSITOR_MAX_LAYERS; ++i) {
      c->layers[i].fs = NULL;
      for ( j = 0; j < 3; j++)
         pipe_sampler_view_reference(&c->layers[i].sampler_views[j], NULL);
   }
}

void
vl_compositor_cleanup(struct vl_compositor *c)
{
   assert(c);

   vl_compositor_clear_layers(c);

   cleanup_buffers(c);
   cleanup_shaders(c);
   cleanup_pipe_state(c);
}

void
vl_compositor_set_csc_matrix(struct vl_compositor *c, const float matrix[16])
{
   struct pipe_transfer *buf_transfer;

   assert(c);

   memcpy
   (
      pipe_buffer_map(c->pipe, c->csc_matrix,
                      PIPE_TRANSFER_WRITE | PIPE_TRANSFER_DISCARD,
                      &buf_transfer),
		matrix,
		sizeof(csc_matrix)
   );

   pipe_buffer_unmap(c->pipe, buf_transfer);
}

void
vl_compositor_set_buffer_layer(struct vl_compositor *c,
                               unsigned layer,
                               struct pipe_video_buffer *buffer,
                               struct pipe_video_rect *src_rect,
                               struct pipe_video_rect *dst_rect)
{
   struct pipe_sampler_view **sampler_views;
   unsigned i;

   assert(c && buffer);

   assert(layer < VL_COMPOSITOR_MAX_LAYERS);

   c->used_layers |= 1 << layer;
   c->layers[layer].clearing = true;
   c->layers[layer].fs = c->fs_video_buffer;

   sampler_views = buffer->get_sampler_view_components(buffer);
   for (i = 0; i < 3; ++i) {
      c->layers[layer].samplers[i] = c->sampler_linear;
      pipe_sampler_view_reference(&c->layers[layer].sampler_views[i], sampler_views[i]);
   }

   calc_src_and_dst(&c->layers[layer], buffer->width, buffer->height,
                    src_rect ? *src_rect : default_rect(&c->layers[layer]),
                    dst_rect ? *dst_rect : default_rect(&c->layers[layer]));
}

void
vl_compositor_set_palette_layer(struct vl_compositor *c,
                                unsigned layer,
                                struct pipe_sampler_view *indexes,
                                struct pipe_sampler_view *palette,
                                struct pipe_video_rect *src_rect,
                                struct pipe_video_rect *dst_rect)
{
   assert(c && indexes && palette);

   assert(layer < VL_COMPOSITOR_MAX_LAYERS);

   c->used_layers |= 1 << layer;
   c->layers[layer].clearing = false;
   c->layers[layer].fs = c->fs_palette;
   c->layers[layer].samplers[0] = c->sampler_linear;
   c->layers[layer].samplers[1] = c->sampler_nearest;
   c->layers[layer].samplers[2] = NULL;
   pipe_sampler_view_reference(&c->layers[layer].sampler_views[0], indexes);
   pipe_sampler_view_reference(&c->layers[layer].sampler_views[1], palette);
   pipe_sampler_view_reference(&c->layers[layer].sampler_views[2], NULL);
   calc_src_and_dst(&c->layers[layer], indexes->texture->width0, indexes->texture->height0,
                    src_rect ? *src_rect : default_rect(&c->layers[layer]),
                    dst_rect ? *dst_rect : default_rect(&c->layers[layer]));

}

void
vl_compositor_set_rgba_layer(struct vl_compositor *c,
                             unsigned layer,
                             struct pipe_sampler_view *rgba,
                             struct pipe_video_rect *src_rect,
                             struct pipe_video_rect *dst_rect)
{
   assert(c && rgba);

   assert(layer < VL_COMPOSITOR_MAX_LAYERS);

   c->used_layers |= 1 << layer;
   c->layers[layer].clearing = rgba->swizzle_a == PIPE_SWIZZLE_ONE;
   c->layers[layer].fs = c->fs_rgba;
   c->layers[layer].samplers[0] = c->sampler_linear;
   c->layers[layer].samplers[1] = NULL;
   c->layers[layer].samplers[2] = NULL;
   pipe_sampler_view_reference(&c->layers[layer].sampler_views[0], rgba);
   pipe_sampler_view_reference(&c->layers[layer].sampler_views[1], NULL);
   pipe_sampler_view_reference(&c->layers[layer].sampler_views[2], NULL);
   calc_src_and_dst(&c->layers[layer], rgba->texture->width0, rgba->texture->height0,
                    src_rect ? *src_rect : default_rect(&c->layers[layer]),
                    dst_rect ? *dst_rect : default_rect(&c->layers[layer]));
}

void
vl_compositor_render(struct vl_compositor *c,
                     struct pipe_surface           *dst_surface,
                     struct pipe_video_rect        *dst_area,
                     struct pipe_video_rect        *dst_clip)
{
   struct pipe_scissor_state scissor;

   assert(c);
   assert(dst_surface);

   c->fb_state.width = dst_surface->width;
   c->fb_state.height = dst_surface->height;
   c->fb_state.cbufs[0] = dst_surface;
   
   if (dst_area) {
      c->viewport.scale[0] = dst_area->w;
      c->viewport.scale[1] = dst_area->h;
      c->viewport.translate[0] = dst_area->x;
      c->viewport.translate[1] = dst_area->y;
   } else {
      c->viewport.scale[0] = dst_surface->width;
      c->viewport.scale[1] = dst_surface->height;
      c->viewport.translate[0] = 0;
      c->viewport.translate[1] = 0;
   }

   if (dst_clip) {
      scissor.minx = dst_clip->x;
      scissor.miny = dst_clip->y;
      scissor.maxx = dst_clip->x + dst_clip->w;
      scissor.maxy = dst_clip->y + dst_clip->h;
   } else {
      scissor.minx = 0;
      scissor.miny = 0;
      scissor.maxx = dst_surface->width;
      scissor.maxy = dst_surface->height;
   }

   gen_vertex_data(c);

   if (c->dirty_tl.x < c->dirty_br.x || c->dirty_tl.y < c->dirty_br.y) {
      util_clear_render_target(c->pipe, dst_surface, c->clear_color, 0, 0, dst_surface->width, dst_surface->height);
      c->dirty_tl.x = c->dirty_tl.y = 1.0f;
      c->dirty_br.x = c->dirty_br.y = 0.0f;
   }

   c->pipe->set_scissor_state(c->pipe, &scissor);
   c->pipe->set_framebuffer_state(c->pipe, &c->fb_state);
   c->pipe->set_viewport_state(c->pipe, &c->viewport);
   c->pipe->bind_vs_state(c->pipe, c->vs);
   c->pipe->set_vertex_buffers(c->pipe, 1, &c->vertex_buf);
   c->pipe->bind_vertex_elements_state(c->pipe, c->vertex_elems_state);
   c->pipe->set_constant_buffer(c->pipe, PIPE_SHADER_FRAGMENT, 0, c->csc_matrix);
   c->pipe->bind_blend_state(c->pipe, c->blend);
   c->pipe->bind_rasterizer_state(c->pipe, c->rast);

   draw_layers(c);
}

bool
vl_compositor_init(struct vl_compositor *c, struct pipe_context *pipe)
{
   csc_matrix csc_matrix;

   c->pipe = pipe;

   if (!init_pipe_state(c))
      return false;

   if (!init_shaders(c)) {
      cleanup_pipe_state(c);
      return false;
   }
   if (!init_buffers(c)) {
      cleanup_shaders(c);
      cleanup_pipe_state(c);
      return false;
   }

   vl_compositor_clear_layers(c);

   vl_csc_get_matrix(VL_CSC_COLOR_STANDARD_IDENTITY, NULL, true, csc_matrix);
   vl_compositor_set_csc_matrix(c, csc_matrix);

   c->clear_color[0] = c->clear_color[1] = 0.0f;
   c->clear_color[2] = c->clear_color[3] = 0.0f;
   vl_compositor_reset_dirty_area(c);

   return true;
}