Revert of Move npot resizing out of GrContext and simplify GrContext texture functions.

include/gpu/GrPaint.h

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef GrPaint_DEFINED
 #define GrPaint_DEFINED
 
 #include "GrColor.h"
 #include "GrFragmentStage.h"
 #include "GrXferProcessor.h"
 #include "effects/GrPorterDuffXferProcessor.h"
 
 #include "SkXfermode.h"
 
 /**
  * The paint describes how color and coverage are computed at each pixel by GrContext draw
  * functions and the how color is blended with the destination pixel.
  *
  * The paint allows installation of custom color and coverage stages. New types of stages are
  * created by subclassing GrProcessor.
  *
  * The primitive color computation starts with the color specified by setColor(). This color is the
- * input to the first color stage. Each color stage feeds its output to the next color stage.
+ * input to the first color stage. Each color stage feeds its output to the next color stage. The
+ * final color stage's output color is input to the color filter specified by
+ * setXfermodeColorFilter which produces the final source color, S.
  *
  * Fractional pixel coverage follows a similar flow. The coverage is initially the value specified
  * by setCoverage(). This is input to the first coverage stage. Coverage stages are chained
  * together in the same manner as color stages. The output of the last stage is modulated by any
  * fractional coverage produced by anti-aliasing. This last step produces the final coverage, C.
  *
- * setXPFactory is used to control blending between the output color and dest. It also implements
- * the application of fractional coverage from the coverage pipeline.
+ * setBlendFunc() specifies blending coefficients for S (described above) and D, the initial value
+ * of the destination pixel, labeled Bs and Bd respectively. The final value of the destination
+ * pixel is then D' = (1-C)*D + C*(Bd*D + Bs*S).
+ *
+ * Note that the coverage is applied after the blend. This is why they are computed as distinct
+ * values.
+ *
+ * TODO: Encapsulate setXfermodeColorFilter in a GrProcessor and remove from GrPaint.
  */
 class GrPaint {
 public:
     GrPaint();
 
     GrPaint(const GrPaint& paint) { *this = paint; }
 
     ~GrPaint() {}
 
     /**
@@ skipping 93 matching lines @@
     SkSTArray<4, GrFragmentStage>   fColorStages;
     SkSTArray<2, GrFragmentStage>   fCoverageStages;
 
     bool                            fAntiAlias;
     bool                            fDither;
 
     GrColor                         fColor;
 };
 
 #endif