[_CDCSL_93-16_]<1>Cedar>release>ColorTrix>CtMod.mesa

CtMod.mesa

Bloomenthal, September 10, 1992 4:35 pm PDT

Heckbert, June 1, 1988 0:36:58 am PDT

Glassner, December 11, 1989 11:12:03 pm PST

DIRECTORY CtBasic, CtMap, G2dMatrix, G2dVector, ImagerColor, ImagerSample, ImagerTransformation, SF;

CtMod: CEDAR DEFINITIONS

~ BEGIN

Imported Types

IntegerPair: TYPE ~ CtBasic.IntegerPair;

SampleMaps: TYPE ~ CtBasic.SampleMaps;

PixelArray: TYPE ~ CtBasic.PixelArray;

Cmap: TYPE ~ CtMap.Cmap;

Table: TYPE ~ CtMap.Table;

Matrix: TYPE ~ G2dMatrix.Matrix;

PairSequence: TYPE ~ G2dVector.PairSequence;

Box: TYPE ~ ImagerSample.Box;

SampleMap: TYPE ~ ImagerSample.SampleMap;

Transformation: TYPE ~ ImagerTransformation.Transformation;

Vec: TYPE ~ SF.Vec;

Raster Transformations

TransformProc: TYPE ~ PROC [p: IntegerPair] RETURNS [IntegerPair];

Points transformed beyond the original raster are clipped to the nearest raster point.

TransformMap: PROC [map: SampleMap, transformation: Transformation];

Resample the raster given the transformation.

TransformMaps: PROC [maps: SampleMaps, transformation: Transformation];

Resample the rasters given the transformation.

ArbTransformMap: PROC [map: SampleMap, proc: TransformProc];

Overwrite map such that map(x,y) ¬ map(proc(x,y)).

ArbTransformMaps: PROC [maps: SampleMaps, proc: TransformProc];

Overwrite maps such that maps(x,y) ¬ maps(proc(x,y)).

Palette Procedures

Palette: PROC [maps: SampleMaps, nRows: NAT ¬ 5, smooth: BOOL]

RETURNS [affectedRegion: Box];

Draw the color map palette in the given maps.

Color Map Indirection

Indirect: PROC [map: SampleMap, table: Table, box: Box];

Indirect all pixels within box through the table. No op if map.bpp # 8.

Lum24: PROC [maps: SampleMaps, cmap: Cmap, coeff: ImagerColor.RGB ¬ [.30, .59, .11]];

Compute luminance by indirecting through cmap and weighting by the coefficients.

No op if maps.bpp = 8.

Simple Modifying Procedures

Dif: PROC [map: SampleMap, x0, y0, x1, y1, x2, y2, w, h: NAT];

Display the difference (absolute value) of two windows in a third window, each w by h.

Up: PROC [map: SampleMap, shift: INTEGER];

Move the image up by shift amount; image will wrap-around.

Left: PROC [map: SampleMap, shift: INTEGER];

Move the image left by shift amount; image will wrap-around.

Negate: PROC [map: SampleMap];

Negate the image in the color display.

ReflectH: PROC [map: SampleMap];

Reflect the pixel map about the horizontal mid-line.

ReflectV: PROC [map: SampleMap];

Reflect the pixel map about the vertical mid-line.

MirrorH: PROC [map: SampleMap, topToBottom: BOOL ¬ TRUE];

Mirror the pixel map about the horizontal mid-line.

MirrorV: PROC [map: SampleMap, leftToRight: BOOL ¬ TRUE];

Mirror the pixel map about the vertical mid-line.

Transpose: PROC [map: SampleMap];

Transpose the pixels in the map within a square region of the map.

Rotate: PROC [map: SampleMap, degrees: REAL];

Rotate the map by the given degrees; positive rotation is counter-clockwise.

Add: PROC [dst, map: SampleMap, fbAlpha, fileAlpha: REAL];

Linear interpolation: dst ← (fileAlpha*dst)+(fbAlpha*map).

Lerp: PROC [dst, map: SampleMap, alpha: REAL];

Linear interpolation: dst ← alpha*dst+(1-alpha)*map.

PVal: PROC [map: SampleMap, new: NAT, old: LIST OF NAT];

Set any old valued pixels to the new value.

Gammatize: PROC [maps: SampleMaps, gamma: REAL, x, y, w, h: NAT];

Apply a gamma correction to maps.

Warping

CoonsControl: TYPE ~ RECORD [filter: {point, box} ¬ point, abort: BOOL ¬ FALSE];

PerspWarp: PROC [

texture: PixelArray ¬ NIL, -- source image

dest: SampleMaps, -- destination sample maps

smooth: BOOL ¬ FALSE, -- anti-alias or not?

points: ARRAY [0..4) OF IntegerPair] -- warp quadrilateral

RETURNS [transform: Matrix];

Perform the perspective warping on the input texture; return the perspective transformation.

CoonsWarp: PROC [

pa1, pa2, pa3: PixelArray, -- source (pa1 for bw or r, pa2, 3 for g, b)

curves: ARRAY [0..4) OF PairSequence, -- outline curves

dest: SampleMaps, -- destination sample maps

control: REF CoonsControl ¬ NIL];

Warp the region of the source image bounded by the outline curves into the rectangular destination window. The mapping is a bilinear Coons surface, (see On Coons and Other Methods for the Representation of Curved Sufaces by Forrest, CGIP 1972).

For an 8-bpp source image, pa2 and pa3 is NIL; for 24bpp, pa1, pa2, pa3 are red, green, blue.

Filter options are point sampled (fast) or bilinear (box) filtering (slow).

If control # NIL then filter can be changed or operation aborted during this call.

If control = NIL, then filter type defaults to point sampling.

Pixel Procedures

BiLerp: PROC [pa: PixelArray, x, y: REAL] RETURNS [CARDINAL];

Return the bilinearly interpolated pixel value rounded to the nearest integer.

The pixel array may be 8 or 16 bpp. Bounds fault if x or y is out of range.

BiLerpReal: PROC [pa: PixelArray, x, y: REAL] RETURNS [REAL];

Return the bilinearly interpolated pixel value. The pixel array must be 8 bpp only.

Bounds fault if x or y is out of range.

END.