buildgradient

Contents: Description, Arguments, Usage, Examples, Related Functions, Source Supported Under Version: > 1.00 Current .dvrc Version: 1.00 Description Builds a 1-dimensional colour gradient from an arbitrary number of colour control points Arguments and Return Values Arguments: the width/size of the gradient, an optional smoothing window, and at least two control points Return Value: A one-dimensional RGB image Usage Syntax: buildgradient(point1position, point1colour ... pointnposition, pointncolour [, width = INT] [, smoothwindow = INT]) buildgradient() builds a 1-dimensional colour gradient from the specified parameters, similar to the gradient editor in Adobe Photoshop® and the GNU Image Manipulation Program. It is mainly intended for use as one of the inputs to the applypalette function. This function accepts an arbitrary number of colour control points. Each point is defined by two input variables, with the first representing its position along the gradient (starting at 1), and the second representing its colour in RGB colourspace. The optional width parameter controls the size of the gradient. If it is not specified, it defaults to 65536. The optional smoothwindow parameter specifies a sliding window (in terms of pixels) which is used to smooth the generated gradient. If it is not specified, it defaults to 1 (no smoothing). Each colour should be specified as a 1x1x3 float array representing the RGB value, with each component between 0.0 and 1.0. In the following examples, the resulting 1-dimensional gradients have been scaled into 2-dimensional images of a reasonable size for display. The commands to do this have been omitted to save space. Examples The 'Doppler Shift White' colour gradient from The Mirror's Surface Breaks: dv> gradient_colour_00 1x1x3 array of float, bsq format [12 bytes] 1.000000000 0.0000000000 0.0000000000 dv> gradient_colour_01 1x1x3 array of float, bsq format [12 bytes] 1.000000000 1.000000000 1.000000000 dv> gradient_colour_02 1x1x3 array of float, bsq format [12 bytes] 0.0000000000 0.0000000000 1.000000000 dv> g = buildgradient(1, gradient_colour_00, 32768, gradient_colour_01, 65536, gradient_colour_02) Generating a gradient using 3 colours and 3 channels. 65536x1x3 array of float, bsq format [786,432 bytes] The 'Hue Wheel' colour gradient from The Mirror's Surface Breaks: dv> gradient_colour_00 1x1x3 array of float, bsq format [12 bytes] 1.000000000 0.0000000000 0.0000000000 dv> gradient_colour_01 1x1x3 array of float, bsq format [12 bytes] 1.000000000 1.000000000 0.0000000000 dv> gradient_colour_02 1x1x3 array of float, bsq format [12 bytes] 0.0000000000 1.000000000 0.0000000000 dv> gradient_colour_03 1x1x3 array of float, bsq format [12 bytes] 0.0000000000 1.000000000 1.000000000 dv> gradient_colour_04 1x1x3 array of float, bsq format [12 bytes] 0.0000000000 0.0000000000 1.000000000 dv> gradient_colour_05 1x1x3 array of float, bsq format [12 bytes] 1.000000000 0.0000000000 1.000000000 dv> gradient_colour_06 1x1x3 array of float, bsq format [12 bytes] 1.000000000 0.0000000000 0.0000000000 dv> g = buildgradient(1, gradient_colour_00, 10922, gradient_colour_01, 21844, gradient_colour_02, 32768, gradient_colour_03, 43688, gradient_colour_04, 54610, gradient_colour_05, 65536, gradient_colour_06) Generating a gradient using 7 colours and 3 channels. 65536x1x3 array of float, bsq format [786,432 bytes] The 'Vegetation Index Single Scale' colour gradient from The Mirror's Surface Breaks: dv> gradient_colour_00 1x1x3 array of float, bsq format [12 bytes] 0.5000076294 0.5000076294 0.5000076294 dv> gradient_colour_01 1x1x3 array of float, bsq format [12 bytes] 0.1250019073 0.1250019073 0.1250019073 dv> gradient_colour_02 1x1x3 array of float, bsq format [12 bytes] 0.3058823943 0.2039216012 0.1450980008 dv> gradient_colour_03 1x1x3 array of float, bsq format [12 bytes] 0.5411764979 0.5411764979 0.03921569139 dv> gradient_colour_04 1x1x3 array of float, bsq format [12 bytes] 0.0000000000 1.000000000 0.0000000000 dv> g = buildgradient(1, gradient_colour_00, 16384, gradient_colour_01, 21299, gradient_colour_02, 41288, gradient_colour_03, 65536, gradient_colour_04) Generating a gradient using 5 colours and 3 channels. 65536x1x3 array of float, bsq format [786,432 bytes] The 'Classic Thermograph' colour gradient from The Mirror's Surface Breaks: dv> gradient_colour_00 1x1x3 array of float, bsq format [12 bytes] 0.0000000000 0.0000000000 0.0000000000 dv> gradient_colour_01 1x1x3 array of float, bsq format [12 bytes] 1.000000000 0.0000000000 1.000000000 dv> gradient_colour_02 1x1x3 array of float, bsq format [12 bytes] 0.0000000000 0.0000000000 1.000000000 dv> gradient_colour_03 1x1x3 array of float, bsq format [12 bytes] 0.0000000000 1.000000000 1.000000000 dv> gradient_colour_04 1x1x3 array of float, bsq format [12 bytes] 0.0000000000 1.000000000 0.0000000000 dv> gradient_colour_05 1x1x3 array of float, bsq format [12 bytes] 1.000000000 1.000000000 0.0000000000 dv> gradient_colour_06 1x1x3 array of float, bsq format [12 bytes] 1.000000000 0.0000000000 0.0000000000 dv> gradient_colour_07 1x1x3 array of float, bsq format [12 bytes] 1.000000000 1.000000000 1.000000000 dv> g = buildgradient(1, gradient_colour_00, 6554, gradient_colour_01, 16384, gradient_colour_02, 26214, gradient_colour_03, 36045, gradient_colour_04, 45875, gradient_colour_05, 52429, gradient_colour_06, 65536, gradient_colour_07) Generating a gradient using 8 colours and 3 channels. 65536x1x3 array of float, bsq format [786,432 bytes] The 'Modern Thermograph 3' colour gradient from The Mirror's Surface Breaks: dv> gradient_colour_00 1x1x3 array of float, bsq format [12 bytes] 0.0000000000 0.0000000000 0.0000000000 dv> gradient_colour_01 1x1x3 array of float, bsq format [12 bytes] 0.03921569139 0.0000000000 0.6980391741 dv> gradient_colour_02 1x1x3 array of float, bsq format [12 bytes] 1.000000000 0.0000000000 0.0000000000 dv> gradient_colour_03 1x1x3 array of float, bsq format [12 bytes] 1.000000000 0.9882352948 0.0000000000 dv> gradient_colour_04 1x1x3 array of float, bsq format [12 bytes] 1.000000000 1.000000000 1.000000000 dv> g = buildgradient(1, gradient_colour_00, 13763, gradient_colour_01, 27525, gradient_colour_02, 58327, gradient_colour_03, 65536, gradient_colour_04) Generating a gradient using 5 colours and 3 channels. 65536x1x3 array of float, bsq format [786,432 bytes]

DavinciWiki Mini-Nav Bar Contents Functions Function Categories Common Procedures Glossary Download Davinci Change Log News Mailing List Contact Developers davinci-dev [AT] mars.asu.edu All other topics See navigation on the left Related Functions applypalette dshadow.dvrc (Beta) buildgradient() Recent Library Changes Change Log Created On: 07-16-2012 Modified On: 05-02-2013