urho3d/Engine/UI/UIBatch.h

//
// Urho3D Engine
// Copyright (c) 2008-2011 Lasse Öörni
//
// 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, sublicense, 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 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 NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS 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.
//

#pragma once

#include "Color.h"
#include "PODVector.h"
#include "Rect.h"
#include "GraphicsDefs.h"

#include <vector>

class PixelShader;
class Graphics;
class Texture;
class UIElement;
class VertexShader;

/// UI rendering quad
struct UIQuad
{
    /// Left coordinate
    int left_;
    /// Top coordinate
    int top_;
    /// Right coordinate
    int right_;
    /// Bottom coordinate
    int bottom_;
    /// Left texture coordinate
    short leftUV_;
    /// Top texture coordinate
    short topUV_;
    /// Right texture coordinate
    short rightUV_;
    /// Bottom texture coordinate
    short bottomUV_;
    /// Top left color
    unsigned topLeftColor_;
    /// Top right color
    unsigned topRightColor_;
    /// Bottom left color
    unsigned bottomLeftColor_;
    /// Bottom right color
    unsigned bottomRightColor_;
};

/// UI rendering draw call
class UIBatch
{
public:
    /// Construct with defaults
    UIBatch() :
        texture_(0),
        quads_(0),
        quadStart_(0),
        quadCount_(0)
    {
    }
    
    /// Begin adding quads
    void Begin(PODVector<UIQuad>* quads);
    /// Add a quad
    void AddQuad(UIElement& element, int x, int y, int width, int height, int texOffsetX, int texOffsetY);
    /// Add a quad with scaled texture
    void AddQuad(UIElement& element, int x, int y, int width, int height, int texOffsetX, int texOffsetY, int texWidth, int texHeight);
    /// Add a quad with custom color
    void AddQuad(UIElement& element, int x, int y, int width, int height, int texOffsetX, int texOffsetY, int texWidth, int texHeight, const Color& color);
    /// Merge with another batch
    bool Merge(const UIBatch& batch);
    /// Draw
    void Draw(Graphics* graphics, VertexShader* vs, PixelShader* ps) const;
    
    /// Add or merge a batch
    static void AddOrMerge(const UIBatch& batch, PODVector<UIBatch>& batches);
    /// Return an interpolated color for an UI element
    static unsigned GetInterpolatedColor(UIElement& element, int x, int y);
    
    /// Blending mode
    BlendMode blendMode_;
    /// Scissor rectangle
    IntRect scissor_;
    /// Texture
    Texture* texture_;
    /// Quads
    PODVector<UIQuad>* quads_;
    /// Quad start index
    unsigned quadStart_;
    /// Number of quads
    unsigned quadCount_;
};