context.c

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    oldDrawable = pwglGetCurrentDC();
    if(pwglMakeCurrent(hdc, ctx) == FALSE) {
        ERR("Cannot activate context to set up defaults\n");
        goto out;
    }

    TRACE("Setting up the screen\n");
    /* Clear the screen */
    glClearColor(1.0, 0.0, 0.0, 0.0);
    checkGLcall("glClearColor");
    glClearIndex(0);
    glClearDepth(1);
    glClearStencil(0xffff);

    checkGLcall("glClear");

    glColor3f(1.0, 1.0, 1.0);
    checkGLcall("glColor3f");

    glEnable(GL_LIGHTING);
    checkGLcall("glEnable");

    glLightModeli(GL_LIGHT_MODEL_LOCAL_VIEWER, GL_TRUE);
    checkGLcall("glLightModeli(GL_LIGHT_MODEL_LOCAL_VIEWER, GL_TRUE);");

    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_EXT);
    checkGLcall("glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_EXT);");

    glLightModeli(GL_LIGHT_MODEL_COLOR_CONTROL, GL_SEPARATE_SPECULAR_COLOR);
    checkGLcall("glLightModeli(GL_LIGHT_MODEL_COLOR_CONTROL, GL_SEPARATE_SPECULAR_COLOR);");

    glPixelStorei(GL_PACK_ALIGNMENT, This->surface_alignment);
    checkGLcall("glPixelStorei(GL_PACK_ALIGNMENT, This->surface_alignment);");
    glPixelStorei(GL_UNPACK_ALIGNMENT, This->surface_alignment);
    checkGLcall("glPixelStorei(GL_UNPACK_ALIGNMENT, This->surface_alignment);");

    if(GL_SUPPORT(APPLE_CLIENT_STORAGE)) {
        /* Most textures will use client storage if supported. Exceptions are non-native power of 2 textures
         * and textures in DIB sections(due to the memory protection).
         */
        glPixelStorei(GL_UNPACK_CLIENT_STORAGE_APPLE, GL_TRUE);
        checkGLcall("glPixelStorei(GL_UNPACK_CLIENT_STORAGE_APPLE, GL_TRUE)");
    }
    if(GL_SUPPORT(ARB_VERTEX_BLEND)) {
        /* Direct3D always uses n-1 weights for n world matrices and uses 1 - sum for the last one
         * this is equal to GL_WEIGHT_SUM_UNITY_ARB. Enabling it doesn't do anything unless
         * GL_VERTEX_BLEND_ARB isn't enabled too
         */
        glEnable(GL_WEIGHT_SUM_UNITY_ARB);
        checkGLcall("glEnable(GL_WEIGHT_SUM_UNITY_ARB)");
    }
    if(GL_SUPPORT(NV_TEXTURE_SHADER2)) {
        glEnable(GL_TEXTURE_SHADER_NV);
        checkGLcall("glEnable(GL_TEXTURE_SHADER_NV)");

        /* Set up the previous texture input for all shader units. This applies to bump mapping, and in d3d
         * the previous texture where to source the offset from is always unit - 1.
         */
        for(s = 1; s < GL_LIMITS(textures); s++) {
            GL_EXTCALL(glActiveTextureARB(GL_TEXTURE0_ARB + s));
            glTexEnvi(GL_TEXTURE_SHADER_NV, GL_PREVIOUS_TEXTURE_INPUT_NV, GL_TEXTURE0_ARB + s - 1);
            checkGLcall("glTexEnvi(GL_TEXTURE_SHADER_NV, GL_PREVIOUS_TEXTURE_INPUT_NV, ...\n");
        }
    }
    if(GL_SUPPORT(ARB_POINT_SPRITE)) {
        for(s = 0; s < GL_LIMITS(textures); s++) {
            GL_EXTCALL(glActiveTextureARB(GL_TEXTURE0_ARB + s));
            glTexEnvi(GL_POINT_SPRITE_ARB, GL_COORD_REPLACE_ARB, GL_TRUE);
            checkGLcall("glTexEnvi(GL_POINT_SPRITE_ARB, GL_COORD_REPLACE_ARB, GL_TRUE)\n");
        }
    }

    if(oldDrawable && oldCtx) {
        pwglMakeCurrent(oldDrawable, oldCtx);
    }

out:
    return ret;
}

/*****************************************************************************
 * RemoveContextFromArray
 *
 * Removes a context from the context manager. The opengl context is not
 * destroyed or unset. context is not a valid pointer after that call.
 *
 * Similar to the former call this isn't a performance critical function. A
 * helper function for DestroyContext.
 *
 * Params:
 *  This: Device to activate the context for
 *  context: Context to remove
 *
 *****************************************************************************/
static void RemoveContextFromArray(IWineD3DDeviceImpl *This, WineD3DContext *context) {
    UINT t, s;
    WineD3DContext **oldArray = This->contexts;

    TRACE("Removing ctx %p\n", context);

    This->numContexts--;

    if(This->numContexts) {
        This->contexts = HeapAlloc(GetProcessHeap(), 0, sizeof(*This->contexts) * This->numContexts);
        if(!This->contexts) {
            ERR("Cannot allocate a new context array, PANIC!!!\n");
        }
        t = 0;
        for(s = 0; s < This->numContexts; s++) {
            if(oldArray[s] == context) continue;
            This->contexts[t] = oldArray[s];
            t++;
        }
    } else {
        This->contexts = NULL;
    }

    HeapFree(GetProcessHeap(), 0, context);
    HeapFree(GetProcessHeap(), 0, oldArray);
}

/*****************************************************************************
 * DestroyContext
 *
 * Destroys a wineD3DContext
 *
 * Params:
 *  This: Device to activate the context for
 *  context: Context to destroy
 *
 *****************************************************************************/
void DestroyContext(IWineD3DDeviceImpl *This, WineD3DContext *context) {

    /* check that we are the current context first */
    TRACE("Destroying ctx %p\n", context);
    if(pwglGetCurrentContext() == context->glCtx){
        pwglMakeCurrent(NULL, NULL);
    }

    if(context->isPBuffer) {
        GL_EXTCALL(wglReleasePbufferDCARB(context->pbuffer, context->hdc));
        GL_EXTCALL(wglDestroyPbufferARB(context->pbuffer));
    } else ReleaseDC(context->win_handle, context->hdc);
    pwglDeleteContext(context->glCtx);

    RemoveContextFromArray(This, context);
}

/*****************************************************************************
 * SetupForBlit
 *
 * Sets up a context for DirectDraw blitting.
 * All texture units are disabled, except unit 0
 * Texture unit 0 is activted where GL_TEXTURE_2D is activated
 * fog, lighting, blending, alpha test, z test, scissor test, culling diabled
 * color writing enabled for all channels
 * register combiners disabled, shaders disabled
 * world matris is set to identity, texture matrix 0 too
 * projection matrix is setup for drawing screen coordinates
 *
 * Params:
 *  This: Device to activate the context for
 *  context: Context to setup
 *  width: render target width
 *  height: render target height
 *
 *****************************************************************************/
static inline void SetupForBlit(IWineD3DDeviceImpl *This, WineD3DContext *context, UINT width, UINT height) {
    int i;

    TRACE("Setting up context %p for blitting\n", context);
    if(context->last_was_blit) {
        TRACE("Context is already set up for blitting, nothing to do\n");
        return;
    }
    context->last_was_blit = TRUE;

    /* TODO: Use a display list */

    /* Disable shaders */
    This->shader_backend->shader_cleanup((IWineD3DDevice *) This);
    Context_MarkStateDirty(context, STATE_VSHADER);
    Context_MarkStateDirty(context, STATE_PIXELSHADER);

    /* Disable all textures. The caller can then bind a texture it wants to blit
     * from
     */
    if(GL_SUPPORT(NV_REGISTER_COMBINERS)) {
        glDisable(GL_REGISTER_COMBINERS_NV);
        checkGLcall("glDisable(GL_REGISTER_COMBINERS_NV)");
    }
    if (GL_SUPPORT(ARB_MULTITEXTURE)) {
        /* The blitting code uses (for now) the fixed function pipeline, so make sure to reset all fixed
         * function texture unit. No need to care for higher samplers
         */
        for(i = GL_LIMITS(textures) - 1; i > 0 ; i--) {
            GL_EXTCALL(glActiveTextureARB(GL_TEXTURE0_ARB + i));
            checkGLcall("glActiveTextureARB");

            if(GL_SUPPORT(ARB_TEXTURE_CUBE_MAP)) {
                glDisable(GL_TEXTURE_CUBE_MAP_ARB);
                checkGLcall("glDisable GL_TEXTURE_CUBE_MAP_ARB");
            }
            glDisable(GL_TEXTURE_3D);
            checkGLcall("glDisable GL_TEXTURE_3D");
            glDisable(GL_TEXTURE_2D);
            checkGLcall("glDisable GL_TEXTURE_2D");

            glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
            checkGLcall("glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);");

            Context_MarkStateDirty(context, STATE_TEXTURESTAGE(i, WINED3DTSS_COLOROP));
            Context_MarkStateDirty(context, STATE_SAMPLER(i));
        }
        GL_EXTCALL(glActiveTextureARB(GL_TEXTURE0_ARB));
        checkGLcall("glActiveTextureARB");
    }
    if(GL_SUPPORT(ARB_TEXTURE_CUBE_MAP)) {
        glDisable(GL_TEXTURE_CUBE_MAP_ARB);
        checkGLcall("glDisable GL_TEXTURE_CUBE_MAP_ARB");
    }
    glDisable(GL_TEXTURE_3D);
    checkGLcall("glDisable GL_TEXTURE_3D");
    glEnable(GL_TEXTURE_2D);
    checkGLcall("glEnable GL_TEXTURE_2D");

    glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);

    glMatrixMode(GL_TEXTURE);
    checkGLcall("glMatrixMode(GL_TEXTURE)");
    glLoadIdentity();
    checkGLcall("glLoadIdentity()");
    Context_MarkStateDirty(context, STATE_TRANSFORM(WINED3DTS_TEXTURE0));

    if (GL_SUPPORT(EXT_TEXTURE_LOD_BIAS)) {
        glTexEnvf(GL_TEXTURE_FILTER_CONTROL_EXT,
                  GL_TEXTURE_LOD_BIAS_EXT,
                  0.0);
        checkGLcall("glTexEnvi GL_TEXTURE_LOD_BIAS_EXT ...");
    }
    Context_MarkStateDirty(context, STATE_SAMPLER(0));
    Context_MarkStateDirty(context, STATE_TEXTURESTAGE(0, WINED3DTSS_COLOROP));

    /* Other misc states */
    glDisable(GL_ALPHA_TEST);
    checkGLcall("glDisable(GL_ALPHA_TEST)");
    Context_MarkStateDirty(context, STATE_RENDER(WINED3DRS_ALPHATESTENABLE));
    glDisable(GL_LIGHTING);
    checkGLcall("glDisable GL_LIGHTING");
    Context_MarkStateDirty(context, STATE_RENDER(WINED3DRS_LIGHTING));
    glDisable(GL_DEPTH_TEST);
    checkGLcall("glDisable GL_DEPTH_TEST");
    Context_MarkStateDirty(context, STATE_RENDER(WINED3DRS_ZENABLE));
    glDisable(GL_FOG);
    checkGLcall("glDisable GL_FOG");
    Context_MarkStateDirty(context, STATE_RENDER(WINED3DRS_FOGENABLE));
    glDisable(GL_BLEND);
    checkGLcall("glDisable GL_BLEND");
    Context_MarkStateDirty(context, STATE_RENDER(WINED3DRS_ALPHABLENDENABLE));
    glDisable(GL_CULL_FACE);
    checkGLcall("glDisable GL_CULL_FACE");
    Context_MarkStateDirty(context, STATE_RENDER(WINED3DRS_CULLMODE));
    glDisable(GL_STENCIL_TEST);
    checkGLcall("glDisable GL_STENCIL_TEST");
    Context_MarkStateDirty(context, STATE_RENDER(WINED3DRS_STENCILENABLE));
    if(GL_SUPPORT(ARB_POINT_SPRITE)) {
        glDisable(GL_POINT_SPRITE_ARB);
        checkGLcall("glDisable GL_POINT_SPRITE_ARB");
        Context_MarkStateDirty(context, STATE_RENDER(WINED3DRS_POINTSPRITEENABLE));
    }
    glColorMask(GL_TRUE, GL_TRUE,GL_TRUE,GL_TRUE);
    checkGLcall("glColorMask");
    Context_MarkStateDirty(context, STATE_RENDER(WINED3DRS_CLIPPING));

    /* Setup transforms */
    glMatrixMode(GL_MODELVIEW);
    checkGLcall("glMatrixMode(GL_MODELVIEW)");
    glLoadIdentity();
    checkGLcall("glLoadIdentity()");
    Context_MarkStateDirty(context, STATE_TRANSFORM(WINED3DTS_WORLDMATRIX(0)));

    glMatrixMode(GL_PROJECTION);
    checkGLcall("glMatrixMode(GL_PROJECTION)");
    glLoadIdentity();
    checkGLcall("glLoadIdentity()");
    glOrtho(0, width, height, 0, 0.0, -1.0);
    checkGLcall("glOrtho");
    Context_MarkStateDirty(context, STATE_TRANSFORM(WINED3DTS_PROJECTION));

    context->last_was_rhw = TRUE;
    Context_MarkStateDirty(context, STATE_VDECL); /* because of last_was_rhw = TRUE */

    glDisable(GL_CLIP_PLANE0); checkGLcall("glDisable(clip plane 0)");
    glDisable(GL_CLIP_PLANE1); checkGLcall("glDisable(clip plane 1)");
    glDisable(GL_CLIP_PLANE2); checkGLcall("glDisable(clip plane 2)");
    glDisable(GL_CLIP_PLANE3); checkGLcall("glDisable(clip plane 3)");
    glDisable(GL_CLIP_PLANE4); checkGLcall("glDisable(clip plane 4)");