(*

 * Hedgewars, a free turn based strategy game

 * Copyright (c) 2004-2012 Andrey Korotaev <unC0Rr@gmail.com>

 *

 * 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; version 2 of the License

 *

 * 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, write to the Free Software

 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA

 *)

{$INCLUDE "options.inc"}

unit uTextures;

interface

uses SDLh, uTypes;

function  NewTexture(width, height: Longword; buf: Pointer): PTexture;

procedure Surface2GrayScale(surf: PSDL_Surface);

function  Surface2Tex(surf: PSDL_Surface; enableClamp: boolean): PTexture;

procedure FreeTexture(tex: PTexture);

procedure ComputeTexcoords(texture: PTexture; r: PSDL_Rect; tb: PVertexRect);

procedure initModule;

procedure freeModule;

implementation

uses GLunit, uUtils, uVariables, uConsts, uDebug, uConsole;

var TextureList: PTexture;

procedure SetTextureParameters(enableClamp: Boolean);

begin

    if enableClamp and ((cReducedQuality and rqClampLess) = 0) then

        begin

        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);

        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE)

        end;

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR)

end;

procedure ComputeTexcoords(texture: PTexture; r: PSDL_Rect; tb: PVertexRect);

var x0, y0, x1, y1: Real;

    w, h, aw, ah: LongInt;

const texelOffset = 0.0;

begin

aw:=texture^.atlas^.w;

ah:=texture^.atlas^.h;

if texture^.isRotated then

    begin

    w:=r^.h;

    h:=r^.w;

    end 

else

    begin

    w:=r^.w;

    h:=r^.h;        

    end;

x0:= (r^.x +     texelOffset)/aw;

x1:= (r^.x + w - texelOffset)/aw;

y0:= (r^.y +     texelOffset)/ah;

y1:= (r^.y + h - texelOffset)/ah;

tb^[0].X:= x0;

tb^[0].Y:= y0;

tb^[1].X:= x1;

tb^[1].Y:= y0;

tb^[2].X:= x1;

tb^[2].Y:= y1;

tb^[3].X:= x0;

tb^[3].Y:= y1

end;

procedure ResetVertexArrays(texture: PTexture);

var r: TSDL_Rect;

begin

with texture^ do

begin

    vb[0].X:= 0;

    vb[0].Y:= 0;

    vb[1].X:= w;

    vb[1].Y:= 0;

    vb[2].X:= w;

    vb[2].Y:= h;

    vb[3].X:= 0;

    vb[3].Y:= h;

end;

r.x:= 0;

r.y:= 0;

r.w:= texture^.w;

r.h:= texture^.h;

ComputeTexcoords(texture, @r, @texture^.tb);

end;

function NewTexture(width, height: Longword; buf: Pointer): PTexture;

begin

new(NewTexture);

NewTexture^.PrevTexture:= nil;

NewTexture^.NextTexture:= nil;

NewTexture^.Scale:= 1;

if TextureList <> nil then

    begin

    TextureList^.PrevTexture:= NewTexture;

    NewTexture^.NextTexture:= TextureList

    end;

TextureList:= NewTexture;

// Atlas allocation happens here later on. For now we just allocate one exclusive atlas per sprite

new(NewTexture^.atlas);

NewTexture^.atlas^.w:=width;

NewTexture^.atlas^.h:=height;

NewTexture^.x:=0;

NewTexture^.y:=0;

NewTexture^.w:=width;

NewTexture^.h:=height;

NewTexture^.isRotated:=false;

ResetVertexArrays(NewTexture);

glGenTextures(1, @NewTexture^.atlas^.id);

glBindTexture(GL_TEXTURE_2D, NewTexture^.atlas^.id);

glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, buf);

SetTextureParameters(true);

end;

procedure Surface2GrayScale(surf: PSDL_Surface);

var tw, x, y: Longword;

    fromP4: PLongWordArray;

begin

fromP4:= Surf^.pixels;

for y:= 0 to Pred(Surf^.h) do

    begin

    for x:= 0 to Pred(Surf^.w) do 

        begin

        tw:= fromP4^[x];

        tw:= round((tw shr RShift and $FF) * RGB_LUMINANCE_RED +  

              (tw shr GShift and $FF) * RGB_LUMINANCE_GREEN + 

              (tw shr BShift and $FF) * RGB_LUMINANCE_BLUE);

        if tw > 255 then tw:= 255;

        tw:= (tw and $FF shl RShift) or (tw and $FF shl BShift) or (tw and $FF shl GShift) or (fromP4^[x] and AMask);

        fromP4^[x]:= tw;

        end;

    fromP4:= @(fromP4^[Surf^.pitch div 4])

    end;

end;

function Surface2Tex(surf: PSDL_Surface; enableClamp: boolean): PTexture;

var tw, th, x, y: Longword;

    tmpp: pointer;

    fromP4, toP4: PLongWordArray;

begin

new(Surface2Tex);

Surface2Tex^.PrevTexture:= nil;

Surface2Tex^.NextTexture:= nil;

if TextureList <> nil then

    begin

    TextureList^.PrevTexture:= Surface2Tex;

    Surface2Tex^.NextTexture:= TextureList

    end;

TextureList:= Surface2Tex;

// Atlas allocation happens here later on. For now we just allocate one exclusive atlas per sprite

new(Surface2Tex^.atlas);

Surface2Tex^.w:= surf^.w;

Surface2Tex^.h:= surf^.h;

Surface2Tex^.x:=0;

Surface2Tex^.y:=0;

Surface2Tex^.isRotated:=false;

if (surf^.format^.BytesPerPixel <> 4) then

    begin

    TryDo(false, 'Surface2Tex failed, expecting 32 bit surface', true);

    Surface2Tex^.atlas^.id:= 0;

    exit

    end;

glGenTextures(1, @Surface2Tex^.atlas^.id);

glBindTexture(GL_TEXTURE_2D, Surface2Tex^.atlas^.id);

if SDL_MustLock(surf) then

    SDLTry(SDL_LockSurface(surf) >= 0, true);

fromP4:= Surf^.pixels;

if GrayScale then

    Surface2GrayScale(Surf);

if (not SupportNPOTT) and (not (isPowerOf2(Surf^.w) and isPowerOf2(Surf^.h))) then

    begin

    tw:= toPowerOf2(Surf^.w);

    th:= toPowerOf2(Surf^.h);

    Surface2Tex^.atlas^.w:=tw;

    Surface2Tex^.atlas^.h:=th;

    tmpp:= GetMem(tw * th * surf^.format^.BytesPerPixel);

    fromP4:= Surf^.pixels;

    toP4:= tmpp;

    for y:= 0 to Pred(Surf^.h) do

        begin

        for x:= 0 to Pred(Surf^.w) do

            toP4^[x]:= fromP4^[x];

        for x:= Surf^.w to Pred(tw) do

            toP4^[x]:= 0;

        toP4:= @(toP4^[tw]);

        fromP4:= @(fromP4^[Surf^.pitch div 4])

        end;

    for y:= Surf^.h to Pred(th) do

        begin

        for x:= 0 to Pred(tw) do

            toP4^[x]:= 0;

        toP4:= @(toP4^[tw])

        end;

    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, tw, th, 0, GL_RGBA, GL_UNSIGNED_BYTE, tmpp);

    FreeMem(tmpp, tw * th * surf^.format^.BytesPerPixel)

    end

else

    begin

    Surface2Tex^.atlas^.w:=Surf^.w;

    Surface2Tex^.atlas^.h:=Surf^.h;

    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, surf^.w, surf^.h, 0, GL_RGBA, GL_UNSIGNED_BYTE, surf^.pixels);

    end;

ResetVertexArrays(Surface2Tex);

if SDL_MustLock(surf) then

    SDL_UnlockSurface(surf);

SetTextureParameters(enableClamp);

end;

// deletes texture and frees the memory allocated for it.

// if nil is passed nothing is done

procedure FreeTexture(tex: PTexture);

begin

if tex <> nil then

    begin

    // Atlas cleanup happens here later on. For now we just free as each sprite has one atlas

    Dispose(tex^.atlas);

    if tex^.NextTexture <> nil then

        tex^.NextTexture^.PrevTexture:= tex^.PrevTexture;

    if tex^.PrevTexture <> nil then

        tex^.PrevTexture^.NextTexture:= tex^.NextTexture

    else

        TextureList:= tex^.NextTexture;

    glDeleteTextures(1, @tex^.atlas^.id);

    Dispose(tex);

    end

end;

procedure initModule;

begin

TextureList:= nil;

end;

procedure freeModule;

begin

if TextureList <> nil then

    WriteToConsole('FIXME FIXME FIXME. App shutdown without full cleanup of texture list; read game0.log and please report this problem');

    while TextureList <> nil do 

        begin

        AddFileLog('Sprite not freed: width='+inttostr(LongInt(TextureList^.w))+' height='+inttostr(LongInt(TextureList^.h))+' priority='+inttostr(round(TextureList^.atlas^.priority*1000)));

        FreeTexture(TextureList);

        end

end;

end.