multilines_total_V02

Function call: fn_multilines_total_V02 (uv, color, bgVariable, lines, linewidth, soft, angle, roll)
Example with values: fn_multilines_total_V02 (uv0, float4(0.4.xxx, 1.0), 1.0.xxxx, 20.0, 0.005, 5E-4, -1.0, 0.0) (Result see image)

or Macro call: MULTILINES_TOTAL_V02 (uv, color, bgVariable, lines, linewidth, soft, angle, roll)
(Macro code can be found at the bottom of this page)

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Purpose:
Generating a selectable number of lines of equal distance across the entire frame.
Optimized for vertical lines; recommended application range 0 to 45°.
The angle can be changed by shifting the lower end of the lines without changing the position of the upper end of the line.
The softness of the line edges can be adjusted.
The background texture is added with the bgVariable.
This can be a color, or a texture from a sampler.
More functions and details see the parameter descriptions.

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Requirements

Code (Example as a function):

float4 fn_multilines_total_V02 (float2 uv, float4 color, float4 bgVariable, float lines,
                                float linewidth, float soft, float angle, float roll)
{ 
   float mix = saturate (
      (abs( (uv.x - (roll + uv.y  * angle))
          - (round( (uv.x  - (roll + uv.y * angle ))  * lines)  / lines )
          ) - linewidth
      ) / soft
   );
  
   return lerp (color, bgVariable, mix);
}

Option: Automatic use of minimum edge smoothness for pixel interpolation purposes:
You can replace ` ) / soft with ) / (soft + (1.0 / _OutputWidth)). (1.0 / _OutputWidth)` is the widht of a texel within the output texture.
This creates the necessary edge softness of the lines to minimize pixel jumps and aliasing. (Remember to declare these global variables high up in the code, outside the function.)

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Parameter Description

1. uv:
   Enter the name of the used texture coordinate variable.
   Type: float2
   Recommendation: float2 uv0 : TEXCOORD0 (which may not be used for sampler parameters!)

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1. color:
   Color of the line
   Type: float4 (RGBA)
   • The macro code also works with other float types (eg float3 RGB).
     In any case, it must be the same type as bgVariable

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1. bgVariable:
   The background texture
   Type: float4 (RGBA)
   • The macro code also works with other float types (eg float3 RGB).
     In any case, it must be the same type as color

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1. lines:
   • Number of lines on the top edge of the frame.
     Depending on the angle settings, additional lines may be visible, starting at the right or left edge.
     This parameter only takes into account lines touching the top edge of the frame.
     - Type: scalar float
     - Impermissible value: 0 (would be a division by zero within the code)

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1. linewidth:
   - Line width
   - Type:scalar float
   - Usable value range 0.0 to 0.5
   - If the angle of the lines is not horizontal, then the lines move closer together, because additional lines on the top or bottom edge of the frame fill the vacant areas. When changing angles, the ratio of the line width to the width of the background in between remains approximately constant. As a result, if the angle parameter is other than 0°, the line width becomes narrower than the set value.
   - A set edge softness increases the line width.
   - Examples (horizontal lines without edge softness):
   0.000: Line width 0 pixels
   0.005: Line width 1% of the frame hight
   0.500: Line width over the entire frame height

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1. soft: - Edge softness of the lines.
   - Type:scalar float
   - Usable value range > 0.0 to ~0.5
   - Impermissible value: 0 (would be a division by zero within the code)
   - Examples (vertical lines):
   1E-6 : No softness
   0.005: Softness 1% of the frame width
   - Softness increases the line width. This can far exceed the set line width.
   - The maximum softness is achieved when, with the line width parameter set to zero,
   the width is set only with the softness parameter.
   - Recommended minimum settings to minimize pixel jumps and aliasing:

720p	1080p	UHD
8E-4	5E-4	3E-4

…

1. soft Different requirements for this parameter when using the alternative code ) / (soft + (1.0 / _OutputWidth)):
   - Usable value range 0.0 to 0.5
   - Impermissible values: Negative values (risk of divide by zero within the code)
   - A value of 0.0 automatically applies a minimum edge softness of 1 texel (interlaced projects 2 texel).
   This applies to the 0 ° angle setting. At angles of 45 ° or more, additional edge softness may be required.

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1. angle: - The angle can be changed by shifting the lower end of the lines
   without changing the position of the upper end of the line.
   - Type: scalar float
   - Examples:
   angle = 0.0: Vertical line (for other settings, the angle depends on the project aspect ratio)
   angle = +1.0: Diagonal line from the upper left corner to the lower right corner.
   angle = -1.0: Diagonal line from the upper right corner to the lower left corner.
   - The angle is not proportional to the set value. - There are no 90 ° adjustable
   - For values well above 45 ° another code is recommended: multilines_total_H02 - This parameter also affects the line width.

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1. roll:
   - This rolls the lines in the 90 ° direction to the line.
   - Rising values of roll roll all lines to thr right, sinking values to the left (if an angle of 0° is set).
   - Type: scalar float**
   - Usable value ranges:
   • To position the first line within the texture (which is the only one independent of the number of lines): from 0 to 1
   • Rolling of the lines (keyframing): ~ -1000 to + 1000
     (if this range is exceeded, the mathematical unrealities can be seen.)

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#### Return value:

• The value of the parameter color (the line)
  or the value of the parameterbgVariable
  or a mix of both (edge softness)
• Type: same as color and bgVariable
• Value range: 0.0 to 1.0

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Macro code:

#define MULTILINES_TOTAL_V02(uv,color,bgVariable,lines,linewidth,soft,angle,roll)       \
   lerp (color, bgVariable, saturate  (                                                  \
         (abs( ((uv).x - ((roll) + (uv).y * (angle)))                                    \
             - (round( ((uv).x  - ((roll) + (uv).y * (angle) ))  * (lines))  / (lines) ) \
             ) - (linewidth)                                                            \
         ) / (soft)                                                                      \
   ))

Screenshot