components/viz/service/display/geometry_binding.h

// Copyright 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_VIZ_SERVICE_DISPLAY_GEOMETRY_BINDING_H_
#define COMPONENTS_VIZ_SERVICE_DISPLAY_GEOMETRY_BINDING_H_

#include <stdint.h>

#include "gpu/command_buffer/client/gles2_interface.h"
#include "third_party/khronos/GLES2/gl2.h"
#include "third_party/khronos/GLES2/gl2ext.h"
#include "ui/gfx/geometry/rect_f.h"

namespace viz {

struct GeometryBindingVertex {
  float a_position[3];
  float a_texCoord[2];
  // Index of the vertex, divide by 4 to have the matrix for this quad.
  float a_index;
};

struct GeometryBindingQuad {
  GeometryBindingQuad();
  GeometryBindingQuad(const GeometryBindingVertex& vert0,
                      const GeometryBindingVertex& vert1,
                      const GeometryBindingVertex& vert2,
                      const GeometryBindingVertex& vert3);
  GeometryBindingVertex v0, v1, v2, v3;
};
static_assert(sizeof(GeometryBindingQuad) == 24 * sizeof(float),
              "struct Quad should be densely packed");

struct GeometryBindingQuadIndex {
  GeometryBindingQuadIndex();
  GeometryBindingQuadIndex(uint16_t index0,
                           uint16_t index1,
                           uint16_t index2,
                           uint16_t index3,
                           uint16_t index4,
                           uint16_t index5);

  uint16_t data[6];
};
static_assert(sizeof(GeometryBindingQuadIndex) == 6 * sizeof(uint16_t),
              "struct QuadIndex should be densely packed");

struct GeometryBinding {
  // All layer shaders share the same attribute locations for the vertex
  // positions and texture coordinates. This allows switching shaders without
  // rebinding attribute arrays.
  static int PositionAttribLocation() { return 0; }
  static int TexCoordAttribLocation() { return 1; }
  static int TriangleIndexAttribLocation() { return 2; }
};

void SetupGLContext(gpu::gles2::GLES2Interface* gl,
                    GLuint quad_elements_vbo,
                    GLuint quad_vertices_vbo);

}  // namespace viz

#endif  // COMPONENTS_VIZ_SERVICE_DISPLAY_GEOMETRY_BINDING_H_