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LUA - Drawing a tiled image

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Is there any draw texture function that can tile the texture, or do I have to make a loop drawing my texture to create the effect. Context:DrawTexture does not seem to handle tiling.

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For this I would just make a slight change to the existing shader used for DrawImage by adding a scale uniform to it since the command GraphicsDriver::TileImage is not official and is not available for lua. Also the post that TJ links to asked about clipping a drawn image. It could be done via drawing to a buffer but you could also just make another slight modification to the 'drawimage.shader' by adding another uniform to set the X&Y start of the clipped image used in conjunction with the scale uniform.


Fragment portion of the 'drawimage.shader':

#version 400

uniform vec4 drawcolor;
uniform sampler2D texture0;
uniform vec2 scale = vec2(1.0,1.0); //added for tiling
uniform vec2 clipcoords = vec2(0.0,0.0); //added for clipping

in vec2 vTexCoords0;

out vec4 fragData0;

void main(void)
   fragData0 = drawcolor * texture(texture0, vTexCoords0 *scale + clipcoords);



Then to use:

  • shader = Shader:Load("Shaders/Drawing/drawimage.shader")
  • shader:SetVec2("scale", Vec2(#,#)) --the default is vec2(1.0,1.0) so it doesn't effect the normal drawimage command
  • shader:SetVec2("clipcoords", Vec2(#,#)) --the default is vec2(0.0,0.0) so it doesn't effect the normal drawimage command
  • context:DrawImage()


Edit -- I changed the above shader code to make the scale a Vec2 value in case you only wished to tile the image in one direction.


Edit2 - I changed the fragData0 line to multiply by scale prior to adding the clipccords.

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