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- _____________________________
-
- Chapter 4
- Vistapro User Manual
- _____________________________
-
- CONTROL PANELS
-
-
- The Vistapro Control Panels are split into three main sections,
- which we call the Upper, Middle and Lower Control Panels. In
- addition, there is a Color Control Panel.
-
- The map in the window represents the landscape area you loaded
- into Vistapro. The small black + symbol on the map is the
- Target. The small black box symbol is the Camera.
-
- UPPER CONTROL PANEL
- -------------------
- The target represents the point at which you are aiming the
- camera. Its location is measured in meters from the lower left
- hand corner of the topographic map and in meters above sea
- level. After selecting the Target button on the Control Panel,
- you can place the mouse pointer anywhere over the landscape and
- click the left mouse button, setting a new target position in
- the X and Y direction. The Z, or height value, is set to the
- elevation of the landscape at that X-Y coordinate. That is, the
- Z value in the target represents the actual elevation of the
- landscape at that point.
-
- As an alternative, you can place the target precisely by
- entering locations directly into the X, Y and Z numerical
- gadgets. To change a value, select the appropriate numerical
- gadget by clicking the left mouse button in the numerical
- gadget. Use normal editing techniques to change the values.
- (Backspace, delete, etc.)
-
- You may also delete the entire contents of the gadget by
- pressing the SPACE bar. This works in all the numerical gadgets
- in Vistapro. When finished editing press the ENTER key or the
- left mouse button to accept the new value. Press the ESCAPE key
- or the right mouse button to stop editing and restore the
- original value. See also Locking Functions.
-
- Camera
- ------
- The camera represents the location of a hypothetical camera
- used to take a scenic picture. Its location is measured in
- meters from the lower left hand corner of the topographic map
- and in meters above sea level. The X coordinate is from left to
- right on the topographic map. The Y coordinate is from bottom
- to top on the topographic map, and the Z coordinate is in
- meters above sea level. Select Camera on the Control Panel.
-
- By placing the pointer anywhere over the landscape and clicking
- the left mouse button, you can select a new camera position in
- the X and Y direction, and the Z or height value changes with
- the elevation of the landscape. The Z value of the camera is
- set to 30 meters above the landscape. Alternatively, one can
- place the camera precisely by entering locations directly into
- the X, Y and Z numerical gadgets.
-
- To change a value, select the appropriate numerical gadget by
- clicking the left mouse button inside the gadget. Use normal
- editing techniques to change the gadget values (backspace,
- delete, etc.). Delete the entire contents of the gadget by
- pressing the SPACE bar. This works in all the numerical gadgets
- in Vistapro. When finished editing press the ENTER key or the
- left mouse button to accept the new value. Press the ESCAPE key
- or the right mouse button to stop editing and restore the
- original value. See also Locking Functions
-
- Locking Functions
- -----------------
- Other tools that you can use with both the camera and target
- functions are the X, Y and Z locks. You can use the locks when
- you want to restrain the target or camera from moving in one or
- more directions. For instance, if you want to move the camera
- to a new location on the landscape without changing its
- altitude, you could depress the Z lock and then click on a new
- camera location. You will see that the X and Y coordinates of
- the camera have changed but that the Z value has remained the
- same.
-
- Of course there are two other ways of achieving this same
- result: you could simply type the new X and Y locations into
- the camera X and Y numerical gadgets, or you could click the
- mouse on the new camera location (with the Z lock not set) and
- then type in the desired altitude. Vistapro will restrain both
- the camera and target X, Y, and Z values as long as the locks
- are depressed.
-
- dR dR displays the distance in meters between camera and
- target. This distance is the radius from the target. You
- can use this value to step closer to or away from the
- target - just as one might do when taking a photograph.
- When you type in a new distance value Vistapro will change
- the camera's X, Y, and Z coordinates to match the desired
- distance as well as it can. The Bank, Heading, and Pitch
- values will not change.
-
- dX dX displays the difference between camera and target X
- dimension values. The user can change this value by
- entering a new value in the dX numerical gadget. Changing
- this value moves the camera to reflect the new distance.
- The Heading and Pitch of the camera may also change to
- keep the camera pointed at the target.
-
- dY dY displays the difference between camera and target Y
- dimension values. The user can change this value by
- entering a new value in the dY numerical gadget. Changing
- this value moves the camera to reflect the new distance.
- The Heading and Pitch of the camera may also change to
- keep the camera pointed at the target.
-
- dZ dZ displays the difference between camera and target Z
- dimension values. The user can change this value by
- entering a new value in the dZ numerical gadget. Changing
- this value moves the camera to reflect the new distance.
- The Heading and Pitch of the camera may also change to
- keep the camera pointed at the target.The following
- descriptions use an airplane as a model to explain axes.
-
- Bank
- ----
- Bank controls the rotational angle of the camera around its
- longitudinal axis. Imagine an airplane. You can describe the
- longitudinal axis as an invisible line drawn from the tail of
- the airplane to the nose. Any rotation that causes one wing to
- dip and the other to raise is a rotation around the
- longitudinal axis. A positive rotation around this axis would
- cause rotation in a clockwise fashion as viewed from the tail.
- The left wing would raise and the right wing would lower. Note
- that when the camera rotates clockwise the view that is
- rendered will appear to have rotated in the opposite direction.
-
- Head
- ----
- Heading describes the rotational angle of the camera around its
- Z axis relative to the landscape. Imagine an airplane . You can
- describe the Z axis as a line drawn from the top of the
- airplane to its bottom. Any rotation around this axis causes
- the airplane to turn right or left. A positive rotation causes
- the airplane to turn right.
-
- Pitch
- -----
- Pitch is the rotational angle of the camera around its wing
- axis. Once again, imagine an airplane. A line drawn through the
- wings from the left side of the airplane to the right side
- describes the pitch axis. Any rotation around this axis causes
- the airplane to move the nose either up or down, with a
- positive rotation causing the nose to go up.
-
-
- MIDDLE CONTROL PANEL
- --------------------
-
- Sea
- ---
- By setting the sea level, you can sink the landscape into the
- sea to that level. All points below this level become sea level
- (0 meters), and all points above this level have that value
- subtracted.
-
- For example, if you select 1000 meters as sea level, all points
- below 1000 meters will sink to 0, 2000 meters will sink down to
- 1000 meters, 3000 meters will sink to 2000 meters, etc.Vistapro
- will erase rivers and lakes (if present) when it generates a
- new sea level. Vistapro will need to color and shade the
- landscape again.Vistapro has a button for selecting sea level.
- You click on the Sea button and then select the level by
- clicking on the topographic map. You can specify the Sea level
- explicitly by typing the value into the numerical gadget
- immediately below the Sea button (See also Waves).
-
- Tree
- ----
- You can use the Tree level button to set the timber line, the
- altitude above which there are no trees. The timber line is a
- "fuzzy" value. Just as in nature, some trees will appear above
- the tree line and some bare areas will appear below it.
-
- Vistapro's AI (Artificial Intelligence) rules will compensate
- for features of the landscape. Trees generally will not cover
- the face of a cliff even though the entire cliff may be below
- the tree line. Trees may grow upward into a valley (more water
- is available at the bottom of a valley) and a ridge will tend
- to be devoid of trees (ridges tend to dry out from exposure to
- the wind).
-
- If the DrwTre (draw tree) button is not selected Vistapro will
- not actually draw the trees, it will just use the tree colors
- to color the ground.You can use the Tree button to select the
- tree level. Depress the Tree button and then click on the
- topographic map at a location which has the desired altitude.
- You may also numerically specify a tree level by typing a value
- into the numerical gadget located below the Tree button.
-
- Snow
- ----
- The Snow level is the lowest elevation where Vistapro will
- cover the landscape with snow. The AI rules in Vistapro use
- this value to calculate where to use the snow colors. Vistapro
- will compensate for cliffs, ridges, valleys, rivers and lakes
- in an attempt to mimic natural snow cover.Snow colors don't
- have to be the colors of snow.
-
- You can use any colors you like--just keep in mind that the
- snow colors will be placed on the landscape following the AI
- rules for snow. For instance, you can set the snow colors to
- shades of gray to make mountain tops look like barren rock. The
- barren rocky areas will appear to flow down into valleys just
- as snow would.
-
- You can use the Snow button to select the snow level. Depress
- the Snow button and then click on the topographic map at a
- location which has the desired altitude. You may also
- numerically specify a snow line by typing a value into the
- numerical gadget located below the Snow button.
-
- Haze
- ----
- In the real world, the farther away an object is, the more it
- is occluded by the atmosphere. The haze function in Vistapro
- simulates this effect, adding to the three-dimensional feel of
- the resulting image.
-
- You can specify how thick the haze is by changing the Haze
- value in Vistapro. (You can also change the color of the haze--
- see chapter 6, Color Control Panel.) You enter the Haze value
- by entering a number in the numerical gadget below the Haze
- button.
-
- * A value of 0 will completely eliminate the haze effect
- * Small values (below 100) will give very little haze
- * Medium values (100-1000) will give medium haze
- * High values (over 1000) will create very thick fog.
-
- You can also "automatically" calculate the haze value by
- pressing the Haze button. Vistapro will generate a value based
- upon the distance between the camera and the target. The closer
- the two are, the thicker (higher value) the haze.
-
- We tried to arrange it so that setting the haze value this way
- generates haze that first becomes significant at distances
- about the same as that between the camera and target.
-
- Lake
- ----
- The lake function adds lakes to a landscape. Select Lake on the
- Control Panel. Then, using the mouse, place the pointer on the
- landscape at the lake level desired, and click the left mouse
- button.
-
- Example: If one places the pointer in a shallow valley at 2100
- meters, water will begin to fill the valley until it reaches
- the 2100 meter mark, as it would in nature.
-
- If there is any portion along the edge of the valley that is
- below the 2100 meter mark, water will spill out of the valley
- and begin to flood other parts of the landscape. This may not
- be the desired effect, and it should be kept in mind when using
- the Lake function.
-
- If uncertain about landscape heights, move the mouse pointer
- around any suspect areas watching the Z value on the status
- line. Then find the lowest point in the pass to determine the
- maximum safe altitude for creating the lake. Lake generation
- can be aborted by pressing the ESCAPE key or the right mouse
- button while the lake is being generated.
-
- To create a lake, press the Lake button and then click on a
- starting point on the topographic map. You will see the lake
- being created on the topographic map in black. Once the lake
- has been completed the black lake will be redrawn in blue.
-
- River
- -----
- Vistapro's River function creates rivers which flow downhill
- from the selected starting point. If a river reaches a
- depression it will slowly fill it (creating a pond or lake)
- until the lake overflows.
-
- The river will continue flowing down hill until it reaches the
- ocean or the edge of the topographic map. You may stop the flow
- of a river by pressing the ESCAPE key or the right mouse
- button. Although you can always fill a lake using the River
- function and wait until the lake fills up, it is generally
- faster to fill lakes using the Lake function.
-
- To create a river, press the River button and then click on a
- starting point on the topographic map. You will see the river
- being created on the topographic map in black. Once the river
- has been completed the black river will be redrawn in blue.
-
- If you start a river on an existing river or lake, the river
- will continue until it reaches sea level or the edge of the
- topo map. A new river (one started where there was not
- originally a river or lake) will also stop at any existing
- water. This allows you to create many tributaries to a river
- without the main river getting very wide and deep.
-
- Of course, if you want the main river to significantly widen,
- start a new river on top of the old one as many times as you
- like. It will grow wider with each iteration.You generally will
- want to start rivers at the head of a valley, but it is
- possible to start a river anywhere on the topographic map.
-
- Smooth
- ------
- The Smoothing function smooths or erodes the landscape,
- removing the harsher, more jagged edges of hills and mountains.
- Smoothing often improves the appearance of landscapes, and it
- is especially useful when dealing with fractal landscapes. You
- should use the smoothing function sparingly with DEM files if
- data integrity is important, as it distorts data.
-
- Pressing the Smooth button on the Control Panel will invoke the
- smoothing function. This is a repeatable, refining function,
- meaning that it can be run over and over again, smoothing
- (eroding) the landscape more on each pass.
-
- Smoothing is also used to obtain snow covered peaks. Because of
- the design rules of the AI algorithms, and as is also true in
- nature, it is very rare that the summits or peaks of mountains
- are completely snow covered. It is more often the case that due
- to the steep nature of the cliff faces and other contributing
- aspects, such as wind and snow weight, snow does not cover the
- peaks of most mountains. However, since it may be desirable
- artistically to create a completely snow-covered mountain,
- smoothing the mountains will often give this effect.
-
- Enlarge
- -------
- The enlarge function allows you to select a portion of the
- landscape and enlarge it to fill the entire topographic area.
- The intermediate data points are either filled with the average
- of the points around them or filled with duplicates of the
- nearest point .
-
- To invoke this function press the Enlarge button. You will then
- see a box that follows the mouse cursor around the screen.
- Place the box over the section that you want to enlarge and
- press the left mouse button. Vistapro will open a requestor
- near the top of the screen asking you to select either the
- Interpolate (average) or Duplicate mode. Select the desired
- mode and the area inside the box will be enlarged to fit the
- entire topographic area. Any rivers, lakes, or oceans will be
- lost.
-
- The differences between the two modes is best described by a
- diagram. Consider the side of a small hill viewed from a cross-
- section; in Interpolate mode, the hill will double in size in
- all dimensions and the side of the hill will remain smooth; in
- Duplicate mode the hill will also double in size, but it will
- become stepped:
-
-
- Original data: \
- \____
-
-
-
- Interpolate mode: ____
- \
- \
- \
- \___
- "in between" data is the average of the points around it.
-
-
-
- Duplicate mode: ───┐
- │
- └──┐
- │
- └───
- "in between" data is the same as the points near it.
-
- Waves
- -----
- Vistapro can generate waves on the sea. To enable this feature,
- select Waves from the main control panel before creating the
- sea. To deselect the waves feature, re-select the Waves button.
- When you enable waves, Vistapro will generate them along with
- any new sea that is generated. You can add waves to an already
- generated sea by selecting the Waves function and setting a new
- sea level, or the same sea level (value 0). While Vistapro is
- generating waves, it displays a message on the status line.
-
- Vistapro generates waves (if specified) only when a new sea
- level is set, both on fractal and real-world landscapes.
-
- DrwTre
- ------
- Vistapro has two types of trees that it can draw while
- rendering. Vistapro draws the trees only if the DrwTre (Draw
- Tree) button is depressed. When you press the button a
- requestor will appear at the top left corner of the screen.
- From it you specify the size and type of trees to draw.
-
- The size is specified by the numerical gadget at the center of
- the requestor. You must select the size before the type since
- pressing either of the type buttons will close the requestor.
- Good sizes range from 20 to 80 meters. Very small trees may
- appear too sparse; very large trees will be distorted or
- overwritten by subsequent polygons of the landscape.
-
- After selecting the tree size (or accepting the default) select
- the type by pressing either the Pine or Oak button. Pine trees
- will have roughly triangular shapes like a Christmas tree. Oak
- trees will have roughly round shapes.
-
- Trees may be drawn anywhere that TREE1 through TREE4 (see CMap
- section) colors are used. In addition the number of trees drawn
- is affected by the TreDns (Tree Density) setting.Trees are
- drawn using TREE1 through TREE4 colors, plus a small randomizer
- so that they are not all the same color. You cannot select the
- brown shades Vistapro will use for the tree trunks. The ground
- underneath trees is drawn as a slightly darker shades of BARE1
- through BARE4.
-
- Trees can take a very long time to draw. Depending on how many
- trees are drawn, trees may take more than twice as long to
- render as the same scene without any trees for Vistapro to
- draw.
-
- LckPal
- ------
- Vistapro renders pictures using the PC's 256 color modes.
- Vistapro calculates the best 256 colors to use just before
- rendering each image. The colors it picks are based on the
- colors in the landscape, the current Contrast and Exposure
- settings, and the Haze colors and value. Calculating a new 256
- color palette can be time consuming (about 40 seconds on a 20
- MHz 386) so we have given you the ability to lock the color
- palette.
-
- When the palette is locked Vistapro will continue to use the
- last palette generated. All succeeding images will be drawn
- with that palette until the color palette is unlocked. Locking
- the palette is especially useful when previewing an image,
- playing with the haze settings or the Color Map. When you are
- ready to render the final image, unlock the palette so that
- Vistapro will generate the best possible palette for that
- image. The palette is locked when the LckPal button is
- depressed. It is unlocked when the button is up.
-
- CMap
- ----
- You can select the CMap button to display and activate the
- Color Control Panel. See Color Control Panel for more
- information.
-
- Poly
- ----
- Vistapro produces 131,072 polygons at its finest resolution.
- The Polygon Size function controls the relative coarseness of
- the landscape image. A size of 8 generates 1/64th as many
- polygons (1/8th on each axis) as a size of 1, and they are 64
- (8 x 8) times as large. That is, a landscape can consist of
- 131,072 size 1 polygons, 32,768 size 2 polygons, 8192 size 4
- polygons, or 2048 size 8 polygons.
-
- You can use the larger polygons to generate quick previews of
- landscapes. When you are happy with your camera and target
- placement, use smaller polygons. The smaller the polygons, the
- longer it takes to generate the image. The larger the polygon
- size number, the less detail that will show up in the image,
- because Vistapro is displaying only a fraction of the original
- data.
-
- The lower resolutions (higher poly number, i.e. 4, 8) are
- useful for quick test renderings to check for landscape color,
- light placement, proper framing and exposure settings.
-
- TreDns
- ------
- TreDns (Tree Density) controls how many of the polygons
- assigned TREE1 through TREE4 colors will also have trees drawn
- on them. Useful values range from 0 to 300 with low values
- giving low tree densities, high values giving high densities.
- Values below 0 are treated the same as 0, values above 300 are
- treated the same as 300. A value of 150 will result in one half
- of the TREE colored polygons having trees rendered.
-
- To change the Tree Density value, click on the numerical gadget
- immediately below the TreDns label and type in a new value.
- Press ENTER when finished.
-
- Dither
- ------
- Vistapro generally colors landscapes by altitude. The lowest
- altitudes are colored with TREE1 through TREE4 colors, middle
- altitudes are colored with BARE1 through BARE4 colors, and the
- highest altitudes are colored with SNOW1 through SNOW4 colors.
- Each of the 130,000 triangles that make up the landscape is
- assigned a color, based on its altitude and several other
- factors.
-
- The Dither value sets the fuzziness of the division between
- color bands in Vistapro. A setting of 0 will give the tree-line
- and snow-line very sharp boundaries. The default setting of 200
- gives a moderate amount of dithering of the colors. A large
- value like 1000 will make the colors so dithered that there is
- no visible relationship between altitude and color. To set this
- value, click the mouse pointer on the Dither numerical gadget
- on the Main Control Panel. Change the number from the keyboard
- and press ENTER. Useful values range from 0 to 1000.
-
- VScale
- ------
- Vistapro allows you to vertically re-scale any landscape.
- Typing a number into the Scale numerical gadget will cause
- Vistapro to scale the landscape as requested. For example, if
- you type in 2.0, Vistapro will stretch the landscape out
- vertically so that mountains are twice as tall, etc. Values
- between 0.0 and 1.0 will cause Vistapro to flatten the
- landscape. Values below 0 cause the landscape to flip over
- (valleys become ridges, mountains become pits) before Vistapro
- scales them. The number typed in always results in a landscape
- which is that value times the original landscape. The user can
- save landscapes after scaling.
-
- You can generate some interesting effects with the scaling
- function. You can flip landscapes upside down by using negative
- values. Scaling mountains so that the top will exceed 32000
- meters and then scaling it back down to normal will result in
- mountains with big pits or calderas. Scaling to very large
- values can even cause several layers of this effect. The result
- shows a mountain inside a collapsed mountain inside a collapsed
- mountain. Scaling mountains down until they are very small and
- scaling them back up will result in stepped mountains.
-
- Main
- ----
- The Main button enables and displays the Main Lower Control
- Panel. See Main Lower Control Panel for details.
-
- Lens
- ----
- The Lens button enables and displays the Lens Lower Control
- Panel. You can use this to select the type of lens the Camera
- is using. See Lens Lower Control Panel for details.
-
- Frac
- ----
- The Frac button enables and displays the Fractal Lower Control
- Panel. You should use this when generating random fractal
- landscapes. See Fractal Lower Control Panel for details.
-
- Light
- -----
- The Light button enables and displays the Light Lower Control
- Panel. Use this when selecting the direction and intensity of
- the light source. See Light Lower Control Panel for details.
-
-
- LOWER CONTROL PANELS
- --------------------
- The Lower Control Panels consist of four separate Control
- Panels overlaid on a common space.
-
- MAIN LOWER CONTROL PANEL
- ------------------------
-
- Blend
- -----
- Blend helps reduce the coarse texture of distant parts of the
- landscape. If you select the Blend button, Vistapro will draw
- each polygon with a weighted average color of that polygon and
- the three polygons that border it. This reduces the aliasing of
- distant polygons. It also reduces the color saturation of
- polygons, so its use is optional.
-
- Gshade
- ------
- Gouraud shading produces smooth looking surfaces without
- obvious triangles. It requires about 50% more rendering time.
- Gouraud shading gives a brush like feeling to the landscape, as
- if an artist painted it using oils, rather than the computer
- playing with numbers. Besides filtering out large polygons, it
- adds mood to the landscape. The foreground may appear blurry
- with Gouraud shading.
-
- Range
- -----
- The range value allows you to clip away parts of the landscape
- which are farther away than the range value. For example, if
- the range value is set to 1000, Vistapro will not draw parts of
- the landscape farther away than 1000 meters. The primary reason
- for this function is to show only the parts of the landscape
- very near the camera, making sure that something is not
- blocking the view. You don't want to wait thirty minutes for a
- picture to render just to find out that a tree completely
- blocks the view.
-
- The value 0 is a special case; it disables the Range function.
- Otherwise the value represents the distance from the camera, at
- which the landscape is clipped away. Values below 100 are
- usually not useful. The sky and horizon are not affected by the
- Range function.
-
- The range function can be used to generate a special effect
- while executing a script file. As the camera moves around the
- landscape, only the parts of the landscape near the camera
- (within the Range) will be visible.
-
- Texture
- -------
- Vistapro can add additional texture to nearby polygons by
- breaking them into smaller pieces and drawing each of the
- pieces as slightly different shades. This adds artificial
- detail to nearby areas. There are four different levels of
- detail:
-
- * Off
- * Low
- * Medium
- * High
-
- They are selected by the "O", "L", "M", and "H" buttons below
- the Texture label. The higher the detail level the longer a
- picture will take to render.
-
- PDthr
- -----
- Dithering at the pixel level increases the apparent number of
- colors in the display. Vistapro uses a dithering method which
- allows you to set the amount of dithering used within the
- display. It can be set anywhere from no dithering to so much
- dithering you can no longer recognize the picture. Normal
- values will range from 0 (no dithering), to 100 (a little
- dithering), to 300 and above (significant dithering). When a
- new dither value is entered, Vistapro prompts for ordered or
- random dithering.
-
- Render
- ------
- This starts the generation of a new picture using the current
- settings in the control panels. Vistapro performs several
- functions while rendering. It displays its progress above the
- topographic map in a status window. For most functions, there
- is a continuously updated status count, so that you can monitor
- Vistapro's progress. (See Vistapro Status Window for more
- information.) You can abort the rendering process by pressing
- the ESCAPE key or by pressing and holding down the right mouse
- button until the rendering stops.
-
- View
- ----
- When rendering is complete Vistapro waits for you to press
- either mouse button or the ESCAPE key. It then redisplays the
- control panel and topographic map. If you want to see the same
- picture again you can view it by pressing the View button. The
- picture will remain visible until you press either of the mouse
- buttons or the ESCAPE key.
-
-
- LENS LOWER CONTROL PANEL
- ------------------------
- The camera lens feature represents the lens type of Vistapro's
- imaginary camera.
-
- Wide: The wide angle lens gives a 90 degree field of view. It
- allows you to see a wide area with minimal spherical
- distortion. The wide angle lens has a zoom value (similar
- to the focal length of a real camera) of 16.
-
- Zoom: The Zoom lens has about half the field of view of the
- wide angle lens (about 45 degrees), or you can think of
- it as having twice the magnification. It allows you to
- zoom in on the target. Very little distortion is
- noticeable. The Zoom lens has a zoom value of 32.
-
- Zoom Value: The Zoom value is similar to the focal length of a
- real camera. It represents the width of the field
- of view or the amount of magnification. The lower
- the Zoom value is, the wider the field of view. The
- higher the Zoom value is, the narrower the field of
- view and the greater the magnification.
-
- The lowest valid Zoom value is 1. This is an
- extremely wide angle lens with severe spherical
- distortion. Values below 8 are generally
- impractical but fun to try. You can set the Zoom
- value as high as 30,000, but such high numbers are
- only useful when the camera is very far from the
- landscape (a million meters or so). You will
- probably usually use Zoom values from 16 to 100.
-
-
- FRACTAL LOWER CONTROL PANEL
- ---------------------------
-
- Random
- ------
- Random Landscape Generation allows creation of a vast number of
- completely artificial landscapes. Vistapro supports over four
- billion random fractal landscapes. Each different number in the
- Fractal numerical gadget represents a different landscape. You
- can use negative numbers. Using a number such as -1,231,541
- will create a different landscape than its positive counterpart
- 1,231,541. Select Random on the Fractal Lower Control Panel.
- Notice that a new number has appeared in the numerical gadget.
- The software will then proceed to create a new landscape. If
- this landscape is one which you may want to use again, be
- certain to write down the number so that you can recall it
- again, or save the landscape, using the Save DEM Menu Item.
-
- To recreate a desired landscape, simply reenter its number in
- the numerical gadget and Vistapro will create the same
- landscape again. This method conserves disk storage space much
- more efficiently than saving the entire landscape as a DEM
- file. Alternatively, enter any number desired into the
- numerical gadget and explore landscapes in this fashion.
- Various methods include using special dates such as birthdays
- (minus hyphens or slashes, i.e.. 52262 not 5-22-62), holidays
- and anniversaries. Keep a list of numbers for those landscapes
- that prove to be interesting so that you can share them with
- other owners of Vistapro.
-
- Like the fingerprints of the four billion inhabitants of this
- planet, some Vistapro scenes may look similar, but, upon closer
- examination, each one is individual and distinctive.
-
- Island
- ------
- There are two modes for generating fractal landscapes, Island
- and Floating. In Island mode the four edges of the fractal
- landscape are at the same altitude. This allows you to create
- islands by setting the sea level higher than this edge
- altitude. It also will create seas surrounded by land. See the
- Sea function for details on its function.
-
- In floating mode, the four edges of the landscape are allowed
- to float--that is they are allowed to vary in altitude.
- Floating mode landscapes look like they were clipped out of a
- larger area--similar to real world DEM landscapes.
-
- If the Island button is depressed, fractal landscapes will be
- generated in Island mode; otherwise they will be generated in
- Floating mode.
-
- FrDim
- -----
- The FrDim value controls the Fractal Dimension (height and
- roughness) of the fractal mountains. The value is used for
- subsequently generated fractal landscapes. Typing in a new
- value does not affect the current landscape unless you
- regenerate it. The default value is 100. Larger values will
- generate taller, rougher landscapes. Smaller values will
- generate flatter, smoother landscapes.
-
- Fractlz
- -------
- You can fractalize the current landscape to add fractal detail.
- If the Fractal Dimension is set to low values the effect is to
- smooth the landscape. If the Fractal Dimension setting is high,
- the landscape will become rougher. The fractal divisor buttons
- 1, 2, 4, and 8, immediately below the Fractlz button control
- the scale where the fractalizing occurs. At lower values
- fractal noise is added only at very small scales--the landscape
- will look basically the same shape, just rougher. At higher
- values the landscape will start looking rougher, and at larger
- scales may no longer resemble the original landscape.
-
- Stretch
- -------
- The stretch function changes landscapes by vertically
- stretching existing features. Peaks will grow taller, valleys
- and pits will grow deeper. The scale at which this happens is
- controlled by the Fractal Divisor buttons (1, 2, 4, and 8,
- immediately above the Stretch button). At lower values only the
- smallest features are stretched. At higher values only the
- larger features are stretched. You can stretch landscapes over
- and over again to create a caricature of the original
- landscape.
-
- Fractal Landscape Number
- ------------------------
- This numerical gadget located below the Random button is for
- entering the number of the fractal landscape you want to
- generate. Alternatively, it displays the random number
- generated when you press the Random button. Whether you enter a
- number or it is generated randomly, Vistapro uses the number to
- generate a fractal landscape. To enter your own value, position
- the mouse pointer over the gadget and press the left mouse
- button. The pointer will disappear. Type in your number from
- the keyboard and press ENTER. Vistapro will then generate that
- landscape. Note that the Fractal Dimension and Fractal Divisor
- values are used while generating the landscape.
-
- Fractal Divisor
- ---------------
- The Fractal Divisor buttons are the four buttons located
- between the Fractlz and Stretch buttons. They are labeled 1, 2,
- 4, and 8. The values they represent are used by the fractal
- generation routines. When Vistapro generates a fractal
- landscape (after you press the Random button or enter a value
- into the Fractal Landscape Number gadget) it uses the current
- divisor setting. The smaller the fractal divisor, the larger
- the features of the landscape.
-
- At a setting of 1 very large mountains are generated. At 8,
- many small mountains are built. For the Fractalize and Stretch
- functions the divisor value represents the frequency at which
- the existing landscape data is sampled in order to generate the
- new landscape. See the sections for Fractalize and Stretch for
- more details.
-
-
- LIGHT LOWER CONTROL PANEL
- -------------------------
- Light Source Direction is the direction from which the sun is
- shining, and you use it in combination with the exposure,
- contrast, and shadow settings to determine the location and
- depth of shadows when generating an image. This function
- "moves" the sun.
-
- Whenever this panel is selected several concentric circles will
- be drawn in black over the landscape. These circles are
- reference points so that you can visually estimate the
- declination of the sun. The circles are labeled with the
- declinations that they represent, 75, 60, 45, 30 and 0 degrees
- above the horizon.
-
- A line (the Sun Vector) will be drawn from the center of the
- bulls eye out toward the edge of the landscape. The direction
- of the line indicates the azimuth (direction around the
- horizon) from which the sun is shining. The length of the line
- indicates the declination of the light source. You should think
- of the Sun Vector as a stick stuck in the center of the
- landscape which is pointing at the sun.
-
- Since the topographic map is being viewed from directly
- overhead, the longer the stick appears, the closer the sun is
- to the horizon. If the stick appears very short it is pointing
- nearly straight up.
-
- NSEW
- ----
- Use the North, South, East, and West buttons (labeled N, S, E,
- and W) to quickly set one of four "standard" lighting
- positions. These buttons are positioned so that you can easily
- see from which direction the sun will be shining. When using
- one of these positions the sun is at 45 degrees above the
- horizon. Using these pre-programmed directions speeds up the
- shading phase of rendering when shadows are enabled. After
- clicking on one of these buttons you can see the Sun Vector
- (the line radiating from the center of the "bulls eye") change
- to indicate the new direction.
-
- Custom
- ------
- The Custom button gives you complete control over the direction
- and angle of the light source. Selecting this button causes the
- Sun Vector to follow the mouse pointer as it moves around the
- screen. This represents the position of the sun in the sky.
- Think of the line as a stick pointing at the sun from the
- center of the landscape. Since you are looking down onto the
- landscape from above, the longer the stick is, the closer the
- sun is to the horizon; the shorter the stick is, the closer the
- sun is to directly overhead. The stick points in the direction
- of the sun.
-
- When you have located the desired direction and angle, a single
- click with the left mouse button locks this in place. Using a
- custom light source may increase the amount of time required to
- complete the shading phase of the rendering process when
- shadows are enabled.
-
- Exager
- ------
- The Exager (Exaggeration) button enables exaggerated shading.
- Imagine a ball in front of you, with a light shining on it from
- above. The top of the ball faces the light, and appears very
- bright. Points farther down the sides of the ball reflect less
- light and appear darker. Halfway down the side, the light no
- longer shines on the surface, and it is in shadow. Exaggerated
- shading increases the rate at which the shades darken around
- the sides of the ball. This technique can add detail to the
- image by exaggerating small irregularities on the landscape.
- You will probably want to disable this function when setting
- the sun at low declinations, since the exaggeration makes all
- the flat areas appear very dark.
-
- Azimth
- ------
- Use the Azimuth gadget to set the direction (in degrees from
- due south) from which the sun shines. Zero degrees is due
- south, 90 degrees, due west, 180 degrees, due north and 270 (or
- D90) degrees is due east. Note that this differs from the
- heading, which is measured from due north, as is common in
- navigation.
-
- Declin
- ------
- Use the Declin gadget to set the declination, the angle from
- the horizon from which the sun shines. Zero degrees of
- declination puts the sun right on the horizon, while 90 degrees
- put the sun directly overhead. This is similar to the way Pitch
- is measured for the camera.
-
- Rough
- -----
- The Rough button sets the apparent roughness of the landscape
- when rendered. Vistapro accomplishes this by adding a scaled
- random number to the shade of each polygon, so that some of the
- polygons will be darker than normal and some will be lighter.
- By doing this, large flat areas will appear to have a little
- more detail than they otherwise might. To set this value, click
- the mouse on the Light button located on the Middle Control
- Panel. Click the mouse pointer on the Rough numerical gadget.
- Change the number from the keyboard and press ENTER. Useful
- values range from 0 to 300, with higher values giving rougher
- appearing landscapes. Very large roughness values result in
- unnatural shading.
-
- Shadow
- ------
- Vistapro has the ability to render landscapes with shadows.
- True shadows are very difficult and time consuming to render so
- Vistapro uses a quick, less precise method. Only the landscape
- itself casts shadows; trees do not cast shadows. Shadows will
- not be cast outside the area of the topographic data. Shadows
- are enabled when the Shadow button is depressed. The Shading
- phase will require more time when Shadows are enabled.
-
-
- *** End of Chapter Four ***
-
-