texture.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef BACKENDS_GRAPHICS_OPENGL_TEXTURE_H
#define BACKENDS_GRAPHICS_OPENGL_TEXTURE_H

#include "graphics/opengl/system_headers.h"
#include "graphics/opengl/context.h"
#include "graphics/opengl/texture.h"

#include "graphics/pixelformat.h"
#include "graphics/surface.h"
#include "graphics/blit.h"

#include "common/rect.h"
#include "common/rotationmode.h"

class Scaler;

namespace OpenGL {

class Surface {
public:
    Surface();
    virtual ~Surface() {}

    virtual void destroy() = 0;

    virtual void recreate() = 0;

    virtual void enableLinearFiltering(bool enable) = 0;

    virtual void setRotation(Common::RotationMode rotation) = 0;

    virtual void allocate(uint width, uint height) = 0;

    virtual void setMask(const byte *mask) {}

    void copyRectToTexture(uint x, uint y, uint w, uint h, const void *src, uint srcPitch);

    void fill(uint32 color);
    void fill(const Common::Rect &r, uint32 color);

    void flagDirty() { _allDirty = true; }
    virtual bool isDirty() const { return _allDirty || !_dirtyArea.isEmpty(); }

    virtual uint getWidth() const = 0;
    virtual uint getHeight() const = 0;

    virtual Graphics::PixelFormat getFormat() const = 0;

    virtual Graphics::Surface *getSurface() = 0;
    virtual const Graphics::Surface *getSurface() const = 0;

    virtual bool hasPalette() const { return false; }

    virtual void setColorKey(uint colorKey) {}
    virtual void setPalette(uint start, uint colors, const byte *palData) {}

    virtual void setScaler(uint scalerIndex, int scaleFactor) {}

    virtual void updateGLTexture() = 0;

    virtual const Texture &getGLTexture() const = 0;
protected:
    void clearDirty() { _allDirty = false; _dirtyArea = Common::Rect(); }

    void addDirtyArea(const Common::Rect &r);
    Common::Rect getDirtyArea() const;
private:
    bool _allDirty;
    Common::Rect _dirtyArea;
};

class TextureSurface : public Surface {
public:
    TextureSurface(GLenum glIntFormat, GLenum glFormat, GLenum glType, const Graphics::PixelFormat &format);
    ~TextureSurface() override;

    void destroy() override;

    void recreate() override;

    void enableLinearFiltering(bool enable) override;
    void setRotation(Common::RotationMode rotation) override;

    void allocate(uint width, uint height) override;

    uint getWidth() const override { return _userPixelData.w; }
    uint getHeight() const override { return _userPixelData.h; }

    Graphics::PixelFormat getFormat() const override { return _format; }

    Graphics::Surface *getSurface() override { return &_userPixelData; }
    const Graphics::Surface *getSurface() const override { return &_userPixelData; }

    void updateGLTexture() override;
    const Texture &getGLTexture() const override { return _glTexture; }
protected:
    const Graphics::PixelFormat _format;

    void updateGLTexture(Common::Rect &dirtyArea);

private:
    Texture _glTexture;

    Graphics::Surface _textureData;
    Graphics::Surface _userPixelData;
};

class FakeTextureSurface : public TextureSurface {
public:
    FakeTextureSurface(GLenum glIntFormat, GLenum glFormat, GLenum glType, const Graphics::PixelFormat &format, const Graphics::PixelFormat &fakeFormat);
    ~FakeTextureSurface() override;

    void allocate(uint width, uint height) override;
    void setMask(const byte *mask) override;

    Graphics::PixelFormat getFormat() const override { return _fakeFormat; }

    bool hasPalette() const override { return (_palette != nullptr); }

    void setColorKey(uint colorKey) override;
    void setPalette(uint start, uint colors, const byte *palData) override;

    Graphics::Surface *getSurface() override { return &_rgbData; }
    const Graphics::Surface *getSurface() const override { return &_rgbData; }

    void updateGLTexture() override;
protected:
    void applyPaletteAndMask(byte *dst, const byte *src, uint dstPitch, uint srcPitch, uint srcWidth, const Common::Rect &dirtyArea, const Graphics::PixelFormat &dstFormat, const Graphics::PixelFormat &srcFormat) const;

    Graphics::Surface _rgbData;
    Graphics::PixelFormat _fakeFormat;
    Graphics::FastBlitFunc _blitFunc;
    uint32 *_palette;
    uint8 *_mask;
};

#ifdef USE_SCALERS
class ScaledTextureSurface : public FakeTextureSurface {
public:
    ScaledTextureSurface(GLenum glIntFormat, GLenum glFormat, GLenum glType, const Graphics::PixelFormat &format, const Graphics::PixelFormat &fakeFormat);
    ~ScaledTextureSurface() override;

    void allocate(uint width, uint height) override;

    uint getWidth() const override { return _rgbData.w; }
    uint getHeight() const override { return _rgbData.h; }
    Graphics::PixelFormat getFormat() const override { return _fakeFormat; }

    bool hasPalette() const override { return (_palette != nullptr); }

    Graphics::Surface *getSurface() override { return &_rgbData; }
    const Graphics::Surface *getSurface() const override { return &_rgbData; }

    void updateGLTexture() override;

    void setScaler(uint scalerIndex, int scaleFactor) override;
protected:
    Graphics::Surface *_convData;
    Scaler *_scaler;
    uint _scalerIndex;
    uint _extraPixels;
    uint _scaleFactor;
};
#endif

#if !USE_FORCED_GLES
class TextureTarget;
class CLUT8LookUpPipeline;

class TextureSurfaceCLUT8GPU : public Surface {
public:
    TextureSurfaceCLUT8GPU();
    ~TextureSurfaceCLUT8GPU() override;

    void destroy() override;

    void recreate() override;

    void enableLinearFiltering(bool enable) override;
    void setRotation(Common::RotationMode rotation) override;

    void allocate(uint width, uint height) override;

    bool isDirty() const override { return _paletteDirty || Surface::isDirty(); }

    uint getWidth() const override { return _userPixelData.w; }
    uint getHeight() const override { return _userPixelData.h; }

    Graphics::PixelFormat getFormat() const override;

    bool hasPalette() const override { return true; }

    void setColorKey(uint colorKey) override;
    void setPalette(uint start, uint colors, const byte *palData) override;

    Graphics::Surface *getSurface() override { return &_userPixelData; }
    const Graphics::Surface *getSurface() const override { return &_userPixelData; }

    void updateGLTexture() override;
    const Texture &getGLTexture() const override;

    static bool isSupportedByContext() {
        return OpenGLContext.shadersSupported
            && OpenGLContext.multitextureSupported
            && OpenGLContext.framebufferObjectSupported
            // With 2^-8 precision this is too prone to approximation errors
            && OpenGLContext.textureLookupPrecision > 8;
    }
private:
    void lookUpColors();

    Texture _clut8Texture;
    Texture _paletteTexture;

    TextureTarget *_target;
    CLUT8LookUpPipeline *_clut8Pipeline;

    GLfloat _clut8Vertices[4*2];

    Graphics::Surface _clut8Data;
    Graphics::Surface _userPixelData;

    byte _palette[4 * 256];
    bool _paletteDirty;
};
#endif // !USE_FORCED_GLES

} // End of namespace OpenGL

#endif