我正在處理會支持8個紋理的紋理/地形splatting GLSL着色器。GLSL着色器:var A中的一半顏色值,var B中的另一半,沒有條件語句
我製作的第一個版本使用RGBA作爲輸入 - 每個通道都是每個紋理的強度。
第二個版本我試圖通過將它們分成兩半來使「頻道」加倍。例如;
- R0 =上Texture1
- R64 =半紋理無1
- R127 =質感十足1
- R128 =無紋理5
- R196 =半質地5
- R254 =完整紋理5
andsoforth。
我已經知道,如果在着色器中的語句是非常糟糕的做法 - 它也覺得做錯了什麼。
事情是,我不知道將每個通道的一半用作完整變量的數學函數。
這裏是片段着色器代碼;
varying vec2 v_vTexcoord;
varying vec4 v_vColour;
uniform sampler2D texture; //Texture
uniform float surfWidth;
uniform float surfHeight;
uniform float xpos;
uniform float ypos;
void main()
{
//Setting the main texture position
vec2 texpos = (v_vTexcoord*vec2(surfWidth, surfHeight)) + vec2(xpos, ypos);
//Modulo 1 for repeat, devide by 4 because its a 4x4 texture sheet
float tpx = mod(texpos.x,1.0)/4.0;
float tpy = mod(texpos.y,1.0)/4.0;
//Setup terrain "intensities"
float t1 = 0.0;
float t2 = 0.0;
float t3 = 0.0;
float t4 = 0.0;
float t5 = 0.0;
float t6 = 0.0;
float t7 = 0.0;
float t8 = 0.0;
//Load from the surface (splatmap)
float btr = (v_vColour * texture2D(gm_BaseTexture, v_vTexcoord)).r;
float btg = (v_vColour * texture2D(gm_BaseTexture, v_vTexcoord)).g;
float btb = (v_vColour * texture2D(gm_BaseTexture, v_vTexcoord)).b;
float bta = (v_vColour * texture2D(gm_BaseTexture, v_vTexcoord)).a;
//Calculating what texture to use (also deviding each channel into 2)
if (btr <= 0.5) {
t1 = btr*2.0;
} else {
t5 = (btr-0.5)*2.0;
}
if (btg <= 0.5) {
t2 = btg*2.0;
} else {
t6 = (btg-0.5)*2.0;
}
if (btb <= 0.5) {
t3 = btb*2.0;
} else {
t7 = (btb-0.5)*2.0;
}
if (bta <= 0.5) {
t4 = bta*2.0;
} else {
t8 = (bta-0.5)*2.0;
}
//Get terrain pixels at proper positions
vec4 ter1 = texture2D(texture, vec2(tpx, tpy));
ter1.a = t1;
vec4 ter2 = texture2D(texture, vec2(tpx+0.25, tpy));
ter2.a = t2;
vec4 ter3 = texture2D(texture, vec2(tpx+0.50, tpy));
ter3.a = t3;
vec4 ter4 = texture2D(texture, vec2(tpx+0.75, tpy));
ter4.a = t4;
vec4 ter5 = texture2D(texture, vec2(tpx, tpy+0.25));
ter5.a = t5;
vec4 ter6 = texture2D(texture, vec2(tpx+0.25, tpy+0.25));
ter6.a = t6;
vec4 ter7 = texture2D(texture, vec2(tpx+0.50, tpy+0.25));
ter7.a = t7;
vec4 ter8 = texture2D(texture, vec2(tpx+0.75, tpy+0.25));
ter8.a = t8;
//Output to screen
gl_FragColor =
ter1*vec4(t1) +
ter2*vec4(t2) +
ter3*vec4(t3) +
ter4*vec4(t4) +
ter5*vec4(t5) +
ter6*vec4(t6) +
ter7*vec4(t7) +
ter8*vec4(t8);
}
我敢肯定,我要去給需要這樣的東西clamp()
或lerp()
,但我不能換我的頭周圍..
此外,當紋理重疊,他們得到「光明「(因爲這兩個紋理只是在最後一個語句中添加的......我不知道如何防止這種情況發生,並始終輸出紋理本身的」最大值「(以便它不會」點亮「)。對不起,如果我聽起來很愚蠢,這是我的第一個真正的着色器:)
太棒了!非常感謝:)現在我只需要能夠正確地生成splatmap ..但是這會修復我的着色器故障!再次感謝:)您將很快在www.shootmup.com上看到結果 –