atari-graphics-videl.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_ATARI_VIDEL_H
#define BACKENDS_GRAPHICS_ATARI_VIDEL_H

#include "backends/graphics/atari/atari-graphics.h"

#include "backends/graphics/atari/atari-c2p-asm.h"
#include "backends/graphics/atari/atari-graphics-asm.h"
#include "common/system.h"

class AtariVidelManager : public AtariGraphicsManager {
public:
    AtariVidelManager() {
        // using virtual methods so must be done here
        allocateSurfaces();
    }

    ~AtariVidelManager() {
        // using virtual methods so must be done here
        freeSurfaces();
    }

private:
    void copyRectToSurface(Graphics::Surface &dstSurface, int dstBitsPerPixel, const Graphics::Surface &srcSurface,
                           int destX, int destY,
                           const Common::Rect &subRect) const override {
        // 'pChunkyEnd' is a delicate parameter: the c2p routine compares it to the address register
        // used for pixel reading; two common mistakes:
        // 1. (subRect.left, subRect.bottom) = beginning of the next line *including the offset*
        // 2. (subRect.right, subRect.bottom) = even worse, end of the *next* line, not current one
        const byte *pChunky    = (const byte *)srcSurface.getBasePtr(subRect.left, subRect.top);
        const byte *pChunkyEnd = (const byte *)srcSurface.getBasePtr(subRect.right, subRect.bottom-1);

        byte *pScreen = (byte *)dstSurface.getPixels() + destY * dstSurface.pitch + destX * dstBitsPerPixel/8;

        if (dstBitsPerPixel == 8) {
            if (srcSurface.pitch == subRect.width()) {
                if (srcSurface.pitch == dstSurface.pitch) {
                    asm_c2p1x1_8(pChunky, pChunkyEnd, pScreen);
                    return;
                } else if (srcSurface.pitch == dstSurface.pitch/2) {
                    asm_c2p1x1_8_tt(pChunky, pChunkyEnd, pScreen, dstSurface.pitch);
                    return;
                }
            }

            asm_c2p1x1_8_rect(
                pChunky, pChunkyEnd,
                subRect.width(),
                srcSurface.pitch,
                pScreen,
                dstSurface.pitch);
        } else {
            if (srcSurface.pitch == subRect.width() && srcSurface.pitch/2 == dstSurface.pitch) {
                asm_c2p1x1_4(pChunky, pChunkyEnd, pScreen);
                return;
            }

            asm_c2p1x1_4_rect(
                pChunky, pChunkyEnd,
                subRect.width(),
                srcSurface.pitch,
                pScreen,
                dstSurface.pitch);
        }
    }

    void drawMaskedSprite(Graphics::Surface &dstSurface, int dstBitsPerPixel,
                          const Graphics::Surface &srcSurface, const Graphics::Surface &srcMask,
                          int destX, int destY,
                          const Common::Rect &subRect) override {
        if (dstBitsPerPixel == 4) {
            asm_draw_4bpl_sprite(
                (uint16 *)dstSurface.getPixels(), (const uint16 *)srcSurface.getBasePtr(subRect.left, subRect.top),
                (const uint16 *)srcMask.getBasePtr(subRect.left, subRect.top),
                destX, destY,
                dstSurface.pitch, subRect.width(), subRect.height());
        } else if (dstBitsPerPixel == 8) {
            asm_draw_8bpl_sprite(
                (uint16 *)dstSurface.getPixels(), (const uint16 *)srcSurface.getBasePtr(subRect.left, subRect.top),
                (const uint16 *)srcMask.getBasePtr(subRect.left, subRect.top),
                destX, destY,
                dstSurface.pitch, subRect.width(), subRect.height());
        }
    }

    Common::Rect alignRect(int x, int y, int w, int h) const override {
        return Common::Rect(x & (-16), y, (x + w + 15) & (-16), y + h);
    }
};

#endif