view src/video/sdlgenblit.pl @ 3473:7bdc10624cba

This is terrible, but the OpenGL standard says that lines are half open, which means that one endpoint is not covered so adjoining lines don't overlap. It also doesn't define which end is open, and indeed Mac OS X and Linux differ. Mac OS X seems to leave the second endpoint open, but Linux uses the right-most endpoint for x major lines and the bottom-most endpoint for y major lines.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 21 Nov 2009 07:14:21 +0000
parents 99210400e8b9
children e743b9c3f6d6
line wrap: on
line source

#!/usr/bin/perl -w
#
# A script to generate optimized C blitters for Simple DirectMedia Layer
# http://www.libsdl.org/

use warnings;
use strict;

my %file;

# The formats potentially supported by this script:
# SDL_PIXELFORMAT_INDEX8
# SDL_PIXELFORMAT_RGB332
# SDL_PIXELFORMAT_RGB444
# SDL_PIXELFORMAT_RGB555
# SDL_PIXELFORMAT_ARGB4444
# SDL_PIXELFORMAT_ARGB1555
# SDL_PIXELFORMAT_RGB565
# SDL_PIXELFORMAT_RGB24
# SDL_PIXELFORMAT_BGR24
# SDL_PIXELFORMAT_RGB888
# SDL_PIXELFORMAT_BGR888
# SDL_PIXELFORMAT_ARGB8888
# SDL_PIXELFORMAT_RGBA8888
# SDL_PIXELFORMAT_ABGR8888
# SDL_PIXELFORMAT_BGRA8888
# SDL_PIXELFORMAT_ARGB2101010

# The formats we're actually creating blitters for:
my @src_formats = (
    "RGB888",
    "BGR888",
    "ARGB8888",
    "RGBA8888",
    "ABGR8888",
    "BGRA8888",
);
my @dst_formats = (
    "RGB888",
    "BGR888",
    "ARGB8888",
);

my %format_size = (
    "RGB888" => 4,
    "BGR888" => 4,
    "ARGB8888" => 4,
    "RGBA8888" => 4,
    "ABGR8888" => 4,
    "BGRA8888" => 4,
);

my %format_type = (
    "RGB888" => "Uint32",
    "BGR888" => "Uint32",
    "ARGB8888" => "Uint32",
    "RGBA8888" => "Uint32",
    "ABGR8888" => "Uint32",
    "BGRA8888" => "Uint32",
);

my %get_rgba_string = (
    "RGB888" => "_R = (Uint8)(_pixel >> 16); _G = (Uint8)(_pixel >> 8); _B = (Uint8)_pixel; _A = 0xFF;",
    "BGR888" => "_B = (Uint8)(_pixel >> 16); _G = (Uint8)(_pixel >> 8); _R = (Uint8)_pixel; _A = 0xFF;", "ARGB8888" => "_A = (Uint8)(_pixel >> 24); _R = (Uint8)(_pixel >> 16); _G = (Uint8)(_pixel >> 8); _B = (Uint8)_pixel;",
    "RGBA8888" => "_R = (Uint8)(_pixel >> 24); _G = (Uint8)(_pixel >> 16); _B = (Uint8)(_pixel >> 8); _A = (Uint8)_pixel;",
    "ABGR8888" => "_A = (Uint8)(_pixel >> 24); _B = (Uint8)(_pixel >> 16); _G = (Uint8)(_pixel >> 8); _R = (Uint8)_pixel;",
    "BGRA8888" => "_B = (Uint8)(_pixel >> 24); _G = (Uint8)(_pixel >> 16); _R = (Uint8)(_pixel >> 8); _A = (Uint8)_pixel;",
);

my %set_rgba_string = (
    "RGB888" => "_pixel = ((Uint32)_R << 16) | ((Uint32)_G << 8) | _B;",
    "BGR888" => "_pixel = ((Uint32)_B << 16) | ((Uint32)_G << 8) | _R;",
    "ARGB8888" => "_pixel = ((Uint32)_A << 24) | ((Uint32)_R << 16) | ((Uint32)_G << 8) | _B;",
    "RGBA8888" => "_pixel = ((Uint32)_R << 24) | ((Uint32)_G << 16) | ((Uint32)_B << 8) | _A;",
    "ABGR8888" => "_pixel = ((Uint32)_A << 24) | ((Uint32)_B << 16) | ((Uint32)_G << 8) | _R;",
    "BGRA8888" => "_pixel = ((Uint32)_B << 24) | ((Uint32)_G << 16) | ((Uint32)_R << 8) | _A;",
);

sub open_file {
    my $name = shift;
    open(FILE, ">$name.new") || die "Cant' open $name.new: $!";
    print FILE <<__EOF__;
/* DO NOT EDIT!  This file is generated by sdlgenblit.pl */
/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library 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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken\@libsdl.org
*/
#include "SDL_config.h"

/* *INDENT-OFF* */

__EOF__
}

sub close_file {
    my $name = shift;
    print FILE <<__EOF__;
/* *INDENT-ON* */

/* vi: set ts=4 sw=4 expandtab: */
__EOF__
    close FILE;
    if ( ! -f $name || system("cmp -s $name $name.new") != 0 ) {
        rename("$name.new", "$name");
    } else {
        unlink("$name.new");
    }
}

sub output_copydefs
{
    print FILE <<__EOF__;
extern SDL_BlitFuncEntry SDL_GeneratedBlitFuncTable[];
__EOF__
}

sub output_copyfuncname
{
    my $prefix = shift;
    my $src = shift;
    my $dst = shift;
    my $modulate = shift;
    my $blend = shift;
    my $scale = shift;
    my $args = shift;
    my $suffix = shift;

    print FILE "$prefix SDL_Blit_${src}_${dst}";
    if ( $modulate ) {
        print FILE "_Modulate";
    }
    if ( $blend ) {
        print FILE "_Blend";
    }
    if ( $scale ) {
        print FILE "_Scale";
    }
    if ( $args ) {
        print FILE "(SDL_BlitInfo *info)";
    }
    print FILE "$suffix";
}

sub get_rgba
{
    my $prefix = shift;
    my $format = shift;
    my $string = $get_rgba_string{$format};
    $string =~ s/_/$prefix/g;
    if ( $prefix ne "" ) {
        print FILE <<__EOF__;
            ${prefix}pixel = *$prefix;
__EOF__
    } else {
        print FILE <<__EOF__;
            pixel = *src;
__EOF__
    }
    print FILE <<__EOF__;
            $string
__EOF__
}

sub set_rgba
{
    my $prefix = shift;
    my $format = shift;
    my $string = $set_rgba_string{$format};
    $string =~ s/_/$prefix/g;
    print FILE <<__EOF__;
            $string
            *dst = ${prefix}pixel;
__EOF__
}

sub output_copycore
{
    my $src = shift;
    my $dst = shift;
    my $modulate = shift;
    my $blend = shift;
    my $s = "";
    my $d = "";

    # Nice and easy...
    if ( $src eq $dst && !$modulate && !$blend ) {
        print FILE <<__EOF__;
            *dst = *src;
__EOF__
        return;
    }

    if ( $blend ) {
        get_rgba("src", $src);
        get_rgba("dst", $dst);
        $s = "src";
        $d = "dst";
    } else {
        get_rgba("", $src);
    }

    if ( $modulate ) {
        print FILE <<__EOF__;
            if (flags & SDL_COPY_MODULATE_COLOR) {
                ${s}R = (${s}R * modulateR) / 255;
                ${s}G = (${s}G * modulateG) / 255;
                ${s}B = (${s}B * modulateB) / 255;
            }
            if (flags & SDL_COPY_MODULATE_ALPHA) {
                ${s}A = (${s}A * modulateA) / 255;
            }
__EOF__
    }
    if ( $blend ) {
        print FILE <<__EOF__;
            if (flags & (SDL_COPY_BLEND|SDL_COPY_ADD)) {
                /* This goes away if we ever use premultiplied alpha */
                if (${s}A < 255) {
                    ${s}R = (${s}R * ${s}A) / 255;
                    ${s}G = (${s}G * ${s}A) / 255;
                    ${s}B = (${s}B * ${s}A) / 255;
                }
            }
            switch (flags & (SDL_COPY_MASK|SDL_COPY_BLEND|SDL_COPY_ADD|SDL_COPY_MOD)) {
            case SDL_COPY_MASK:
                if (${s}A) {
                    ${d}R = ${s}R;
                    ${d}G = ${s}G;
                    ${d}B = ${s}B;
                }
                break;
            case SDL_COPY_BLEND:
                ${d}R = ${s}R + ((255 - ${s}A) * ${d}R) / 255;
                ${d}G = ${s}G + ((255 - ${s}A) * ${d}G) / 255;
                ${d}B = ${s}B + ((255 - ${s}A) * ${d}B) / 255;
                break;
            case SDL_COPY_ADD:
                ${d}R = ${s}R + ${d}R; if (${d}R > 255) ${d}R = 255;
                ${d}G = ${s}G + ${d}G; if (${d}G > 255) ${d}G = 255;
                ${d}B = ${s}B + ${d}B; if (${d}B > 255) ${d}B = 255;
                break;
            case SDL_COPY_MOD:
                ${d}R = (${s}R * ${d}R) / 255;
                ${d}G = (${s}G * ${d}G) / 255;
                ${d}B = (${s}B * ${d}B) / 255;
                break;
            }
__EOF__
    }
    if ( $blend ) {
        set_rgba("dst", $dst);
    } else {
        set_rgba("", $dst);
    }
}

sub output_copyfunc
{
    my $src = shift;
    my $dst = shift;
    my $modulate = shift;
    my $blend = shift;
    my $scale = shift;

    output_copyfuncname("static void", $src, $dst, $modulate, $blend, $scale, 1, "\n");
    print FILE <<__EOF__;
{
    const int flags = info->flags;
__EOF__
    if ( $modulate ) {
        print FILE <<__EOF__;
    const Uint32 modulateR = info->r;
    const Uint32 modulateG = info->g;
    const Uint32 modulateB = info->b;
    const Uint32 modulateA = info->a;
__EOF__
    }
    if ( $blend ) {
        print FILE <<__EOF__;
    Uint32 srcpixel;
    Uint32 srcR, srcG, srcB, srcA;
    Uint32 dstpixel;
    Uint32 dstR, dstG, dstB, dstA;
__EOF__
    } elsif ( $modulate || $src ne $dst ) {
        print FILE <<__EOF__;
    Uint32 pixel;
    Uint32 R, G, B, A;
__EOF__
    }
    if ( $scale ) {
        print FILE <<__EOF__;
    int srcy, srcx;
    int posy, posx;
    int incy, incx;

    srcy = 0;
    posy = 0;
    incy = (info->src_h << 16) / info->dst_h;
    incx = (info->src_w << 16) / info->dst_w;

    while (info->dst_h--) {
        $format_type{$src} *src;
        $format_type{$dst} *dst = ($format_type{$dst} *)info->dst;
        int n = info->dst_w;
        srcx = -1;
        posx = 0x10000L;
        while (posy >= 0x10000L) {
            ++srcy;
            posy -= 0x10000L;
        }
        while (n--) {
            if (posx >= 0x10000L) {
                while (posx >= 0x10000L) {
                    ++srcx;
                    posx -= 0x10000L;
                }
                src = ($format_type{$src} *)(info->src + (srcy * info->src_pitch) + (srcx * $format_size{$src}));
__EOF__
        print FILE <<__EOF__;
            }
__EOF__
        output_copycore($src, $dst, $modulate, $blend);
        print FILE <<__EOF__;
            posx += incx;
            ++dst;
        }
        posy += incy;
        info->dst += info->dst_pitch;
    }
__EOF__
    } else {
        print FILE <<__EOF__;

    while (info->dst_h--) {
        $format_type{$src} *src = ($format_type{$src} *)info->src;
        $format_type{$dst} *dst = ($format_type{$dst} *)info->dst;
        int n = info->dst_w;
        while (n--) {
__EOF__
        output_copycore($src, $dst, $modulate, $blend);
        print FILE <<__EOF__;
            ++src;
            ++dst;
        }
        info->src += info->src_pitch;
        info->dst += info->dst_pitch;
    }
__EOF__
    }
    print FILE <<__EOF__;
}

__EOF__
}

sub output_copyfunc_h
{
}

sub output_copyinc
{
    print FILE <<__EOF__;
#include "SDL_video.h"
#include "SDL_blit.h"
#include "SDL_blit_auto.h"

__EOF__
}

sub output_copyfunctable
{
    print FILE <<__EOF__;
SDL_BlitFuncEntry SDL_GeneratedBlitFuncTable[] = {
__EOF__
    for (my $i = 0; $i <= $#src_formats; ++$i) {
        my $src = $src_formats[$i];
        for (my $j = 0; $j <= $#dst_formats; ++$j) {
            my $dst = $dst_formats[$j];
            for (my $modulate = 0; $modulate <= 1; ++$modulate) {
                for (my $blend = 0; $blend <= 1; ++$blend) {
                    for (my $scale = 0; $scale <= 1; ++$scale) {
                        if ( $modulate || $blend || $scale ) {
                            print FILE "    { SDL_PIXELFORMAT_$src, SDL_PIXELFORMAT_$dst, ";
                            my $flags = "";
                            my $flag = "";
                            if ( $modulate ) {
                                $flag = "SDL_COPY_MODULATE_COLOR | SDL_COPY_MODULATE_ALPHA";
                                if ( $flags eq "" ) {
                                    $flags = $flag;
                                } else {
                                    $flags = "$flags | $flag";
                                }
                            }
                            if ( $blend ) {
                                $flag = "SDL_COPY_MASK | SDL_COPY_BLEND | SDL_COPY_ADD | SDL_COPY_MOD";
                                if ( $flags eq "" ) {
                                    $flags = $flag;
                                } else {
                                    $flags = "$flags | $flag";
                                }
                            }
                            if ( $scale ) {
                                $flag = "SDL_COPY_NEAREST";
                                if ( $flags eq "" ) {
                                    $flags = $flag;
                                } else {
                                    $flags = "$flags | $flag";
                                }
                            }
                            if ( $flags eq "" ) {
                                $flags = "0";
                            }
                            print FILE "($flags), SDL_CPU_ANY,";
                            output_copyfuncname("", $src_formats[$i], $dst_formats[$j], $modulate, $blend, $scale, 0, " },\n");
                        }
                    }
                }
            }
        }
    }
    print FILE <<__EOF__;
    { 0, 0, 0, 0, NULL }
};

__EOF__
}

sub output_copyfunc_c
{
    my $src = shift;
    my $dst = shift;

    for (my $modulate = 0; $modulate <= 1; ++$modulate) {
        for (my $blend = 0; $blend <= 1; ++$blend) {
            for (my $scale = 0; $scale <= 1; ++$scale) {
                if ( $modulate || $blend || $scale ) {
                    output_copyfunc($src, $dst, $modulate, $blend, $scale);
                }
            }
        }
    }
}

open_file("SDL_blit_auto.h");
output_copydefs();
for (my $i = 0; $i <= $#src_formats; ++$i) {
    for (my $j = 0; $j <= $#dst_formats; ++$j) {
        output_copyfunc_h($src_formats[$i], $dst_formats[$j]);
    }
}
print FILE "\n";
close_file("SDL_blit_auto.h");

open_file("SDL_blit_auto.c");
output_copyinc();
for (my $i = 0; $i <= $#src_formats; ++$i) {
    for (my $j = 0; $j <= $#dst_formats; ++$j) {
        output_copyfunc_c($src_formats[$i], $dst_formats[$j]);
    }
}
output_copyfunctable();
close_file("SDL_blit_auto.c");