context.c

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/*
 * Context and render target management in wined3d
 *
 * Copyright 2007 Stefan D鰏inger for CodeWeavers
 *
 * 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
 */

#include "config.h"
#include <stdio.h>
#ifdef HAVE_FLOAT_H
# include <float.h>
#endif
#include "wined3d_private.h"

WINE_DEFAULT_DEBUG_CHANNEL(d3d);

#define GLINFO_LOCATION This->adapter->gl_info

/*****************************************************************************
 * Context_MarkStateDirty
 *
 * Marks a state in a context dirty. Only one context, opposed to
 * IWineD3DDeviceImpl_MarkStateDirty, which marks the state dirty in all
 * contexts
 *
 * Params:
 *  context: Context to mark the state dirty in
 *  state: State to mark dirty
 *
 *****************************************************************************/
static void Context_MarkStateDirty(WineD3DContext *context, DWORD state) {
    DWORD rep = StateTable[state].representative;
    DWORD idx;
    BYTE shift;

    if(!rep || isStateDirty(context, rep)) return;

    context->dirtyArray[context->numDirtyEntries++] = rep;
    idx = rep >> 5;
    shift = rep & 0x1f;
    context->isStateDirty[idx] |= (1 << shift);
}

/*****************************************************************************
 * AddContextToArray
 *
 * Adds a context to the context array. Helper function for CreateContext
 *
 * This method is not called in performance-critical code paths, only when a
 * new render target or swapchain is created. Thus performance is not an issue
 * here.
 *
 * Params:
 *  This: Device to add the context for
 *  hdc: device context
 *  glCtx: WGL context to add
 *  pbuffer: optional pbuffer used with this context
 *
 *****************************************************************************/
static WineD3DContext *AddContextToArray(IWineD3DDeviceImpl *This, HWND win_handle, HDC hdc, HGLRC glCtx, HPBUFFERARB pbuffer) {
    WineD3DContext **oldArray = This->contexts;
    DWORD state;

    This->contexts = HeapAlloc(GetProcessHeap(), 0, sizeof(*This->contexts) * (This->numContexts + 1));
    if(This->contexts == NULL) {
        ERR("Unable to grow the context array\n");
        This->contexts = oldArray;
        return NULL;
    }
    if(oldArray) {
        memcpy(This->contexts, oldArray, sizeof(*This->contexts) * This->numContexts);
    }

    This->contexts[This->numContexts] = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(WineD3DContext));
    if(This->contexts[This->numContexts] == NULL) {
        ERR("Unable to allocate a new context\n");
        HeapFree(GetProcessHeap(), 0, This->contexts);
        This->contexts = oldArray;
        return NULL;
    }

    This->contexts[This->numContexts]->hdc = hdc;
    This->contexts[This->numContexts]->glCtx = glCtx;
    This->contexts[This->numContexts]->pbuffer = pbuffer;
    This->contexts[This->numContexts]->win_handle = win_handle;
    HeapFree(GetProcessHeap(), 0, oldArray);

    /* Mark all states dirty to force a proper initialization of the states on the first use of the context
     */
    for(state = 0; state <= STATE_HIGHEST; state++) {
        Context_MarkStateDirty(This->contexts[This->numContexts], state);
    }

    This->numContexts++;
    TRACE("Created context %p\n", This->contexts[This->numContexts - 1]);
    return This->contexts[This->numContexts - 1];
}

/*****************************************************************************
 * CreateContext
 *
 * Creates a new context for a window, or a pbuffer context.
 *
 * * Params:
 *  This: Device to activate the context for
 *  target: Surface this context will render to
 *  win_handle: handle to the window which we are drawing to
 *  create_pbuffer: tells whether to create a pbuffer or not
 *  pPresentParameters: contains the pixelformats to use for onscreen rendering
 *
 *****************************************************************************/
WineD3DContext *CreateContext(IWineD3DDeviceImpl *This, IWineD3DSurfaceImpl *target, HWND win_handle, BOOL create_pbuffer, const WINED3DPRESENT_PARAMETERS *pPresentParms) {
    HDC oldDrawable, hdc;
    HPBUFFERARB pbuffer = NULL;
    HGLRC ctx = NULL, oldCtx;
    WineD3DContext *ret = NULL;
    int s;

    TRACE("(%p): Creating a %s context for render target %p\n", This, create_pbuffer ? "offscreen" : "onscreen", target);

    if(create_pbuffer) {
        HDC hdc_parent = GetDC(win_handle);
        int iPixelFormat = 0;
        short red, green, blue, alphaBits, colorBits;
        short depthBits, stencilBits;

        IWineD3DSurface *StencilSurface = This->stencilBufferTarget;
        WINED3DFORMAT StencilBufferFormat = (NULL != StencilSurface) ? ((IWineD3DSurfaceImpl *) StencilSurface)->resource.format : 0;

        int attribs[256];
        int nAttribs = 0;
        unsigned int nFormats;

#define PUSH1(att)        attribs[nAttribs++] = (att);
#define PUSH2(att,value)  attribs[nAttribs++] = (att); attribs[nAttribs++] = (value);

        /* Retrieve the specifications for the pixelformat from the backbuffer / stencilbuffer */
        getColorBits(target->resource.format, &red, &green, &blue, &alphaBits, &colorBits);
        getDepthStencilBits(StencilBufferFormat, &depthBits, &stencilBits);
        PUSH2(WGL_DRAW_TO_PBUFFER_ARB, 1); /* We need pbuffer support; doublebuffering isn't needed */
        PUSH2(WGL_PIXEL_TYPE_ARB, WGL_TYPE_RGBA_ARB); /* Make sure we don't get a float or color index format */
        PUSH2(WGL_COLOR_BITS_ARB, colorBits);
        PUSH2(WGL_ALPHA_BITS_ARB, alphaBits);
        PUSH2(WGL_DEPTH_BITS_ARB, depthBits);
        PUSH2(WGL_STENCIL_BITS_ARB, stencilBits);
        PUSH1(0); /* end the list */

#undef PUSH1
#undef PUSH2

        /* Try to find a pixelformat that matches exactly. If that fails let ChoosePixelFormat try to find a close match */
        if(!GL_EXTCALL(wglChoosePixelFormatARB(hdc_parent, (const int*)&attribs, NULL, 1, &iPixelFormat, &nFormats)))
        {
            PIXELFORMATDESCRIPTOR pfd;

            TRACE("Falling back to ChoosePixelFormat as wglChoosePixelFormatARB failed\n");

            ZeroMemory(&pfd, sizeof(pfd));
            pfd.nSize      = sizeof(pfd);
            pfd.nVersion   = 1;
            pfd.dwFlags    = PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER_DONTCARE | PFD_DRAW_TO_WINDOW;
            pfd.iPixelType = PFD_TYPE_RGBA;
            pfd.cColorBits = colorBits;
            pfd.cDepthBits = depthBits;
            pfd.cStencilBits = stencilBits;
            pfd.iLayerType = PFD_MAIN_PLANE;

            iPixelFormat = ChoosePixelFormat(hdc_parent, &pfd);
            if(!iPixelFormat) {
                /* If this happens something is very wrong as ChoosePixelFormat barely fails */
                ERR("Can't find a suitable iPixelFormat for the pbuffer\n");
            }
        }

        TRACE("Creating a pBuffer drawable for the new context\n");
        pbuffer = GL_EXTCALL(wglCreatePbufferARB(hdc_parent, iPixelFormat, target->currentDesc.Width, target->currentDesc.Height, 0));
        if(!pbuffer) {
            ERR("Cannot create a pbuffer\n");
            ReleaseDC(win_handle, hdc_parent);
            goto out;
        }

        /* In WGL a pbuffer is 'wrapped' inside a HDC to 'fool' wglMakeCurrent */
        hdc = GL_EXTCALL(wglGetPbufferDCARB(pbuffer));
        if(!hdc) {
            ERR("Cannot get a HDC for pbuffer (%p)\n", pbuffer);
            GL_EXTCALL(wglDestroyPbufferARB(pbuffer));
            ReleaseDC(win_handle, hdc_parent);
            goto out;
        }
        ReleaseDC(win_handle, hdc_parent);
    } else {
        PIXELFORMATDESCRIPTOR pfd;
        int iPixelFormat;
        short red, green, blue, alpha;
        short colorBits;
        short depthBits, stencilBits;
        int res;

        hdc = GetDC(win_handle);
        if(hdc == NULL) {
            ERR("Cannot retrieve a device context!\n");
            goto out;
        }

        /* PixelFormat selection */
        /* TODO: fill cColorBits/cDepthBits with target->resource.format */
        ZeroMemory(&pfd, sizeof(pfd));
        pfd.nSize      = sizeof(pfd);
        pfd.nVersion   = 1;
        pfd.dwFlags    = PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER | PFD_DRAW_TO_WINDOW;/*PFD_GENERIC_ACCELERATED*/
        pfd.iPixelType = PFD_TYPE_RGBA;
        pfd.cColorBits = 32;
        pfd.cDepthBits = 0;
        pfd.cStencilBits = 0;
        pfd.iLayerType = PFD_MAIN_PLANE;

        /* Try to match the colorBits of the d3d format */
        if(getColorBits(target->resource.format, &red, &green, &blue, &alpha, &colorBits))
            pfd.cColorBits = colorBits;

        /* Retrieve the depth stencil format from the present parameters.
         * The choice of the proper format can give a nice performance boost
         * in case of GPU limited programs. */
        if(pPresentParms->EnableAutoDepthStencil) {
            TRACE("pPresentParms->EnableAutoDepthStencil=enabled; using AutoDepthStencilFormat=%s\n", debug_d3dformat(pPresentParms->AutoDepthStencilFormat));
            if(getDepthStencilBits(pPresentParms->AutoDepthStencilFormat, &depthBits, &stencilBits)) {
                pfd.cDepthBits = depthBits;
                pfd.cStencilBits = stencilBits;
            }
        }

        iPixelFormat = ChoosePixelFormat(hdc, &pfd);
        if(!iPixelFormat) {
            /* If this happens something is very wrong as ChoosePixelFormat barely fails */
            ERR("Can't find a suitable iPixelFormat\n");
        }

        DescribePixelFormat(hdc, iPixelFormat, sizeof(pfd), &pfd);
        res = SetPixelFormat(hdc, iPixelFormat, NULL);
        if(!res) {
            int oldPixelFormat = GetPixelFormat(hdc);

            if(oldPixelFormat) {
                /* OpenGL doesn't allow pixel format adjustments. Print an error and continue using the old format.
                 * There's a big chance that the old format works although with a performance hit and perhaps rendering errors. */
                ERR("HDC=%p is already set to iPixelFormat=%d and OpenGL doesn't allow changes!\n", hdc, oldPixelFormat);
            }
            else {
                ERR("SetPixelFormat failed on HDC=%p for iPixelFormat=%d\n", hdc, iPixelFormat);
                return FALSE;
            }
        }
    }

    ctx = pwglCreateContext(hdc);
    if(This->numContexts) pwglShareLists(This->contexts[0]->glCtx, ctx);

    if(!ctx) {
        ERR("Failed to create a WGL context\n");
        if(create_pbuffer) {
            GL_EXTCALL(wglReleasePbufferDCARB(pbuffer, hdc));
            GL_EXTCALL(wglDestroyPbufferARB(pbuffer));
        }
        goto out;
    }
    ret = AddContextToArray(This, win_handle, hdc, ctx, pbuffer);
    if(!ret) {
        ERR("Failed to add the newly created context to the context list\n");
        pwglDeleteContext(ctx);
        if(create_pbuffer) {
            GL_EXTCALL(wglReleasePbufferDCARB(pbuffer, hdc));
            GL_EXTCALL(wglDestroyPbufferARB(pbuffer));
        }
        goto out;
    }
    ret->surface = (IWineD3DSurface *) target;
    ret->isPBuffer = create_pbuffer;
    ret->tid = GetCurrentThreadId();

    TRACE("Successfully created new context %p\n", ret);

    /* Set up the context defaults */
    oldCtx  = pwglGetCurrentContext();