Simple Fixed Function Tutorial

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SimpleFixedFunctionTutorial

The 3DGS-Project can downloaded here http://people.freenet.de/a6world/pst1.zip
(Just replace the PixelShaderCode with the FixedFunctionCode.)

If you extend this tutorial please extend the table at the bottom. Please with screenshot. If another screenshot/project is needed i will upload it. Contact "Rigoletto" at the 3DGS-Forum. Following examples use the project in the pst1.zip

	Here are our four textures, stone, shadow, alpha and grass. The following code parts are the FixedFunctionCode that will produce the effects shown in the pictures beside. Remember we will use the textures in following texture-channels: stone in Texture 0, which is provided in entSkin1 (the applied level texture in WED) shadow in Texture 1, which is provided in entSkin2 (the rendered shadow by the WED-Compiler) alpha in Texture 2, which must be loaded with bmap grass in Texture 3, which must be loaded with bmap
	This and the next code is stupidly, because the engine do this just without function. ColorOp[1] = Disable; // Just switch texture in 1 off (shadow)
	multiply the stone with the shadow texture. stone * shadow ColorArg1[0] = Texture; // Get texture in 0 ColorOp[0] = SelectArg1; // and make it current ColorArg1[1] = Current; // Get current texture (0) ColorOp[1] = Modulate; // and multiply ColorArg2[1] = Texture; // with texture in 1 = (0*1)
	adding the alpha to the stone texture. stone + alpha // For this we must change the textures Texture[0] = <entSkin1>; // block Texture[1] = <mtlSkin1>; // alpha TexCoordIndex[0] = 1; // TexCoordIndex[1] = 1; // ColorArg1[0] = Texture; // Get texture in 0 ColorOp[0] = SelectArg1; // and make it current ColorArg1[1] = Current; // Get current texture (0) ColorOp[1] = Add; // and add ColorArg2[1] = Texture; // with texture in 1 = (0+1)
	subtract the alpha to the stone texture. stone - alpha // For this we must change the textures Texture[0] = <entSkin1>; // block Texture[1] = <mtlSkin1>; // alpha TexCoordIndex[0] = 1; // TexCoordIndex[1] = 1; // ColorArg1[0] = Texture; // Get texture in 0 ColorOp[0] = SelectArg1; // and make it current ColorArg1[1] = Current; // Get current texture (0) ColorOp[1] = Subtract; // and subtract ColorArg2[1] = Texture; // with texture in 1 = (0-1)
]	multiply stone with shadow and adding alpha. (stone * shadow) + alpha ColorArg1[0] = Texture; // Get texture in 0 ColorOp[0] = SelectArg1; // and make it current ColorArg1[1] = Current; // Get current texture (0) ColorOp[1] = Modulate; // and multiply ColorArg2[1] = Texture; // with texture in 1 ColorArg1[2] = Current; // Get current texture (01) ColorOp[2] = Add; // and add ColorArg2[2] = Texture; // with texture in 2 = (01+2) This do the same: ColorArg1[0] = Texture; // Get texture in 0 ResultArg[0] = Temp; // and save it in temp ColorArg1[1] = Texture; // Get texture in 1 ColorOp[1] = SelectArg1; // and make it current ColorArg0[2] = Texture; // Get texture in 2 (alpha) ColorArg1[2] = Current; // Get current texture (shadow) ColorArg2[2] = Temp; // Get texture in temp (stone) ColorOp[2] = MultiplyAdd; // ColorArg1*ColorArg2+ColorArg0
	(stone * shadow) + (alpha * grass) You can see the shadow is not effecting the grass, because it is not multiplied with it. ColorArg1[0] = Texture; // Get texture in 0 ColorOp[0] = SelectArg1; // and make it current ColorArg1[1] = Current; // Get current texture (0) ColorOp[1] = Modulate; // and multiply ColorArg2[1] = Texture; // with texture in 1 ResultArg[1] = Temp; // and save it in temp (01) ColorArg1[2] = Texture; // Get texture in 2 ColorOp[2] = SelectArg1; // and make it current ColorArg1[3] = Current; // Get current texture (2) ColorOp[3] = Modulate; // and multiply ColorArg2[3] = Texture; // with texture in 3 ColorArg1[4] = Current; // Get current texture (23) ColorOp[4] = Add; // and add ColorArg2[4] = Temp; // with texture in temp
	Linear interpolation between the stone and the grass texture. Looks similarly to the code above but the blending is better. The colors are not changed by the alpha texture. // For this we must reorder the textures Texture[0] = <entSkin1>; // block Texture[1] = <mtlSkin2>; // grass Texture[2] = <mtlSkin1>; // alpha Texture[3] = <entSkin2>; // shadow TexCoordIndex[0] = 1; // TexCoordIndex[1] = 1; // TexCoordIndex[2] = 1; // TexCoordIndex[3] = 0; // Must 0 for shadow-map ColorArg1[0] = Texture; // Get texture in 0 ResultArg[0] = Temp; // and save it in temp ColorArg1[1] = Texture; // Get texture in 1 ColorOp[1] = SelectArg1; // and make it current ColorArg0[2] = Texture; // Get texture in 2 (alpha) ColorArg1[2] = Current; // and the current (grass) ColorOp[2] = Lerp; // interpolate ColorArg2[2] = Temp; // and from temp (stone) ColorArg1[3] = Current; // Get current texture (from interpolate) ColorOp[3] = Modulate; // and multiply ColorArg2[3] = Texture; // with texture in 3 (shadow)
	Complement after Texture. // For this we must reorder the textures Texture[0] = <mtlSkin1>; // alpha Texture[1] = <mtlSkin2>; // grass Texture[2] = <entSkin1>; // block Texture[3] = <entSkin2>; // shadow TexCoordIndex[0] = 1; // TexCoordIndex[1] = 1; // TexCoordIndex[2] = 1; // TexCoordIndex[3] = 0; // Must 0 for shadow-map ColorArg1[0] = Texture\|Complement;// Get texture in 0 and invert ResultArg[0] = Temp; // and save it in temp ColorArg1[1] = Texture; // Get texture in 1 ColorOp[1] = SelectArg1; // and make it current ColorArg0[2] = Temp; // Get texture in temp (alpha) ColorArg1[2] = Current; // and the current (grass) ColorOp[2] = Lerp; // interpolate ColorArg2[2] = Texture; // and texture in 2 (stone) ColorArg1[3] = Current; // Get current texture (from interpolate) ColorOp[3] = Modulate; // and multiply ColorArg2[3] = Texture; // with texture in 3 (shadow)
	Coloring with FF // For this we must reorder the textures Texture[0] = <mtlSkin1>; // alpha Texture[1] = <mtlSkin2>; // grass Texture[2] = <entSkin1>; // block Texture[3] = <entSkin2>; // shadow TexCoordIndex[0] = 1; // TexCoordIndex[1] = 1; // TexCoordIndex[2] = 1; // TexCoordIndex[3] = 0; // Must 0 for shadow-map ColorArg1[0] = Texture; // Get texture in 0 and invert ResultArg[0] = Temp; // and save it in temp ColorArg1[1] = Texture; // Get texture in 1 ColorOp[1] = SelectArg1; // and make it current ColorArg0[2] = Temp; // Get texture in temp (alpha) ColorArg1[2] = Current; // and the current (grass) ColorOp[2] = Lerp; // interpolate ColorArg2[2] = Texture; // and texture in 2 (stone) ColorArg1[3] = Current; // Get current texture (from interpolate) ColorOp[3] = Modulate; // and multiply ColorArg2[3] = Texture; // with texture in 3 (shadow) TextureFactor = 0xFF0000; // Set color ColorArg1[4] = TFactor; // choose color ColorOp[4] = Modulate2x; // and multiply with ColorArg2[4] = Current; // the current texture
	Shifting alpha with FF // For this we must reorder the textures Texture[0] = <entSkin1>; // block Texture[1] = <mtlSkin2>; // grass Texture[2] = <mtlSkin1>; // alpha Texture[3] = <entSkin2>; // shadow TexCoordIndex[0] = 1; // TexCoordIndex[1] = 1; // TexCoordIndex[2] = 1; // TexCoordIndex[3] = 0; // Must 0 for shadow-map ColorArg1[0] = Texture; // Get texture in 0 ResultArg[0] = Temp; // and save it in temp ColorArg1[1] = Texture; // Get texture in 1 ColorOp[1] = SelectArg1; // and make it current TextureTransformFlags[2] = Count2; // Select shifting and set matrix values TextureTransform[2] = { 1.0, 0.0, 0.0, 0.0, // xscale, rotate, ------, ------ 0.0, 1.0, 0.0, 0.0, // ------, yscale, ------, ------ 0.0, 0.5, 0.0, 0.0, // xshift, yshift, ------, ------ 0.0, 0.0, 0.0, 0.0 // ------, ------, ------, ------ }; ColorArg0[2] = Texture; // Get texture in 2 (alpha) ColorArg1[2] = Current; // and the current (grass) ColorOp[2] = Lerp; // interpolate ColorArg2[2] = Temp; // and from temp (stone) ColorArg1[3] = Current; // Get current texture (from interpolate) ColorOp[3] = Modulate; // and multiply ColorArg2[3] = Texture; // with texture in 3 (shadow)