[Mesa-dev] [PATCH 02/22] swrast: do fast_copy_pixels() with Map/UnmapRenderbuffer()

[Brian Paul]

On Wed, Dec 21, 2011 at 12:58 PM, Eric Anholt <eric at anholt.net> wrote:
>> -   temp = malloc(width * MAX_PIXEL_BYTES);
>> -   if (!temp) {
>> -      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
>> -      return GL_FALSE;
>> +      /* different src/dst buffers */
>> +      ctx->Driver.MapRenderbuffer(ctx, srcRb, srcX, srcY,
>> +                                  width, height,
>> +                                  GL_MAP_READ_BIT, &srcMap, &srcRowStride);
>> +      if (!srcMap) {
>> +         _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
>> +         return GL_TRUE; /* don't retry with slow path */
>> +      }
>> +      ctx->Driver.MapRenderbuffer(ctx, dstRb, dstX, dstY,
>> +                                  width, height,
>> +                                  GL_MAP_WRITE_BIT, &dstMap, &dstRowStride);
>> +      if (!dstMap) {
>> +         ctx->Driver.UnmapRenderbuffer(ctx, srcRb);
>> +         _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
>> +         return GL_TRUE; /* don't retry with slow path */
>> +      }
>>     }
>>
>>     for (row = 0; row < height; row++) {
>> -      srcRb->GetRow(ctx, srcRb, width, srcX, srcY, temp);
>> -      dstRb->PutRow(ctx, dstRb, width, dstX, dstY, temp, NULL);
>> -      srcY += yStep;
>> -      dstY += yStep;
>> +      memcpy(dstMap, srcMap, widthInBytes);
>> +      dstMap += dstRowStride;
>> +      srcMap += srcRowStride;
>>     }
>
> So, previously we didn't have to worry about X direction for overlap
> because we used a temp between the Get and Put.  Now, I think you need
> to use memmove instead of memcpy.
>
> Patch 1, and 3-7 are:
> Reviewed-by: Eric Anholt <eric at anholt.net>
>
> this one is too if memmove is the solution.

I'll fix that.  Thanks.

-Brian