第二人生的源码分析(十八)人物纹理显示的实现

上面已经介绍怎么样显示Mesh数据，也就是人物模型已经显示出来，那么同样的模型怎么样构造出各种各样的人物来呢？在第二人生里是使用各种各样的纹理图片来实现的。下面就来仔细地分析这段代码，如下：

#001 U32 LLViewerJointMesh::drawShape( F32 pixelArea, BOOL first_pass)

#002 {

#003 if (!mValid || !mMesh || !mFace || !mVisible ||

#004 mFace->mVertexBuffer.isNull() ||

#005 mMesh->getNumFaces() == 0)

#006 {

#007 return 0;

#008 }

#009

这段代码检查Mesh是否有效。

#010 U32 triangle_count = 0;

#011

#012 stop_glerror();

#013

#014 //----------------------------------------------------------------

#015 // setup current color

#016 //----------------------------------------------------------------

#017 if (!gRenderForSelect)

#018 {

#019 if ((mFace->getPool()->getVertexShaderLevel() > 0))

#020 {

#021 glColor(0,0,0,1);

#022

#023 if (gMaterialIndex > 0)

#024 {

#025 glVertexAttrib4fvARB(gMaterialIndex, mColor.mV);

#026 }

#027

#028 if (mShiny && gSpecularIndex > 0)

#029 {

#030 glVertexAttrib4fARB(gSpecularIndex, 1,1,1,1);

#031 }

#032 }

#033 else

#034 {

#035 glColor4fv(mColor.mV);

#036 }

#037 }

#038

这段代码设置人物材料的颜色。

#039 stop_glerror();

#040

#041 LLGLSSpecular specular(LLColor4(1.f,1.f,1.f,1.f), gRenderForSelect ? : mShiny && !(mFace->getPool()->getVertexShaderLevel() > 0));

#042

#043 LLGLEnable texture_2d((gRenderForSelect && isTransparent()) ? GL_TEXTURE_2D : 0);

#044

#045 //----------------------------------------------------------------

#046 // setup current texture

#047 //----------------------------------------------------------------

#048 llassert( !(mTexture.notNull() && mLayerSet) ); // mutually exclusive

#049

#050 if (mTestImageName)

#051 {

#052 LLImageGL::bindExternalTexture( mTestImageName, 0, GL_TEXTURE_2D );

#053

#054 if (mIsTransparent)

#055 {

#056 glColor(1.f, 1.f, 1.f, 1.f);

#057 }

#058 else

#059 {

#060 glColor(, , , 1.f);

#061 glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB);

#062 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_INTERPOLATE_ARB);

#063

#064 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_PREVIOUS_ARB);

#065 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB_ARB, GL_SRC_COLOR);

#066

#067 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE1_RGB_ARB, GL_TEXTURE);

#068 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_RGB_ARB, GL_SRC_COLOR);

#069

#070 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE2_RGB_ARB, GL_TEXTURE);

#071 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND2_RGB_ARB, GL_ONE_MINUS_SRC_ALPHA);

#072 }

#073 }

#074 else if( mLayerSet )

#075 {

#076 if( mLayerSet->hasComposite() )

#077 {

#078 mLayerSet->getComposite()->bindTexture();

#079 }

#080 else

#081 {

#082 llwarns << "Layerset without composite" << llendl;

#083 gImageList.getImage(IMG_DEFAULT)->bind();

#084 }

#085 }

#086 else

#087 if ( mTexture.notNull() )

#088 {

#089 mTexture->bind();

#090 if (!mTexture->getClampS()) {

#091 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);

#092 }

#093 if (!mTexture->getClampT()) {

#094 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

#095 }

#096 }

#097 else

#098 {

#099 gImageList.getImage(IMG_DEFAULT_AVATAR)->bind();

#100 }

#101

#102 LLGLDisable (gRenderForSelect && !isTransparent() ? GL_TEXTURE_2D : 0);

#103

#104 if (gRenderForSelect)

#105 {

#106 if (isTransparent())

#107 {

#108 glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB);

#109 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_REPLACE);

#110 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ALPHA_ARB, GL_MODULATE);

#111

#112 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_PREVIOUS_ARB);

#113 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB_ARB, GL_SRC_COLOR);

#114

#115 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_ALPHA_ARB, GL_TEXTURE); // GL_TEXTURE_ENV_COLOR is

#116 set in renderPass1

#117 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_ALPHA_ARB, GL_SRC_ALPHA);

#118 }

#119 }

#120 else

#121 {

#122 //----------------------------------------------------------------

#123 // by default, backface culling is enabled

#124 //----------------------------------------------------------------

#125 /*if (sRenderPass == AVATAR_RENDER_PASS_CLOTHING_INNER)

#126 {

#127 LLImageGL::bindExternalTexture( sClothingMaskImageName, 1, GL_TEXTURE_2D );

#128

#129 glClientActiveTextureARB(GL_TEXTURE0_ARB);

#130 glActiveTextureARB(GL_TEXTURE0_ARB);

#131 glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB);

#132 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_MODULATE);

#133 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ALPHA_ARB, GL_REPLACE);

#134

#135 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_TEXTURE);

#136 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB_ARB, GL_SRC_COLOR);

#137

#138 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_ALPHA_ARB, GL_PRIMARY_COLOR_ARB);

#139 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_ALPHA_ARB, GL_SRC_ALPHA);

#140

#141 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE1_RGB_ARB, GL_PRIMARY_COLOR_ARB);

#142 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_RGB_ARB, GL_SRC_COLOR);

#143

#144 glClientActiveTextureARB(GL_TEXTURE1_ARB);

#145 glEnable(GL_TEXTURE_2D); // Texture unit 1

#146 glActiveTextureARB(GL_TEXTURE1_ARB);

#147 glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB);

#148 glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, sClothingInnerColor.mV);

#149 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_INTERPOLATE_ARB);

#150 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ALPHA_ARB, GL_REPLACE);

#151

#152 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_ALPHA_ARB, GL_PREVIOUS_ARB);

#153 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_ALPHA_ARB, GL_SRC_ALPHA);

#154

#155 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_CONSTANT_ARB);

#156 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB_ARB, GL_SRC_COLOR);

#157

#158 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE1_RGB_ARB, GL_PREVIOUS_ARB);

#159 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_RGB_ARB, GL_SRC_COLOR);

#160

#161 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE2_RGB_ARB, GL_TEXTURE);

#162 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND2_RGB_ARB, GL_SRC_ALPHA);

#163 }

#164 else if (sRenderPass == AVATAR_RENDER_PASS_CLOTHING_OUTER)

#165 {

#166 glAlphaFunc(GL_GREATER, );

#167 LLImageGL::bindExternalTexture( sClothingMaskImageName, 1, GL_TEXTURE_2D );

#168

#169 glClientActiveTextureARB(GL_TEXTURE0_ARB);

#170 glActiveTextureARB(GL_TEXTURE0_ARB);

#171 glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB);

#172 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_MODULATE);

#173 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ALPHA_ARB, GL_REPLACE);

#174

#175 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_TEXTURE);

#176 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB_ARB, GL_SRC_COLOR);

#177

#178 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_ALPHA_ARB, GL_PRIMARY_COLOR_ARB);

#179 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_ALPHA_ARB, GL_SRC_ALPHA);

#180

#181 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE1_RGB_ARB, GL_PRIMARY_COLOR_ARB);

#182 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_RGB_ARB, GL_SRC_COLOR);

#183

#184 glClientActiveTextureARB(GL_TEXTURE1_ARB);

#185 glEnable(GL_TEXTURE_2D); // Texture unit 1

#186 glActiveTextureARB(GL_TEXTURE1_ARB);

#187 glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB);

#188 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_REPLACE);

#189 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ALPHA_ARB, GL_MODULATE);

#190

#191 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_PREVIOUS_ARB);

#192 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB_ARB, GL_SRC_COLOR);

#193

#194 glTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_ALPHA_ARB, GL_TEXTURE);

#195 glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_ALPHA_ARB, GL_SRC_ALPHA);

#196 }*/

#197 }

#198

这段代码实现纹理图片的设置和纹理参数配置。

#199 mFace->mVertexBuffer->setBuffer(sRenderMask);

#200

#201 U32 start = mMesh->mFaceVertexOffset;

#202 U32 end = start + mMesh->mFaceVertexCount - 1;

#203 U32 count = mMesh->mFaceIndexCount;

#204 U32* indicesp = ((U32*) mFace->mVertexBuffer->getIndicesPointer()) + mMesh->mFaceIndexOffset;

#205

#206 if (mMesh->hasWeights())

#207 {

#208 if ((mFace->getPool()->getVertexShaderLevel() > 0))

#209 {

#210 if (first_pass)

#211 {

#212 uploadJointMatrices();

#213 }

#214 llDrawRangeElements(GL_TRIANGLES, start, end, count, GL_UNSIGNED_INT, indicesp);

#215 }

#216 else

#217 {

#218 llDrawRangeElements(GL_TRIANGLES, start, end, count, GL_UNSIGNED_INT, indicesp);

#219 }

#220 }

#221 else

#222 {

#223 glPushMatrix();

#224 LLMatrix4 jointToWorld = getWorldMatrix();

#225 glMultMatrixf((GLfloat*)jointToWorld.mMatrix);

#226 llDrawRangeElements(GL_TRIANGLES, start, end, count, GL_UNSIGNED_INT, indicesp);

#227 glPopMatrix();

#228 }

#229

#230 triangle_count += mMesh->mFaceIndexCount;

#231

#232 if (mTestImageName)

#233 {

#234 glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

#235 }

#236

#237 /*if (sRenderPass != AVATAR_RENDER_PASS_SINGLE)

#238 {

#239 LLImageGL::unbindTexture(1, GL_TEXTURE_2D);

#240 glActiveTextureARB(GL_TEXTURE1_ARB);

#241 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_MODULATE);

#242

#243 // Return to the default texture.

#244 LLImageGL::unbindTexture(0, GL_TEXTURE_2D);

#245 glClientActiveTextureARB(GL_TEXTURE0_ARB);

#246 glActiveTextureARB(GL_TEXTURE0_ARB);

#247

#248 glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_MODULATE);

#249 glAlphaFunc(GL_GREATER, );

#250 }*/

#251

#252 if (mTexture.notNull()) {

#253 if (!mTexture->getClampS()) {

#254 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);

#255 }

#256 if (!mTexture->getClampT()) {

#257 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

#258 }

#259 }

#260

#261 return triangle_count;

#262 }

最后一段代码实现Mesh数据的显示。

在这个函数里调用下面的函数来绑定纹理到特定的阶段显示：

#001 BOOL LLImageGL::bind(const S32 stage) const

#002 {

#003 if (stage == -1)

#004 {

#005 return FALSE;

#006 }

#007 BOOL res = bindTextureInternal(stage);

#008 //llassert(res);

#009 return res;

#010 }

在函数bindTextureInternal里调用OpenGL函数设置特定的纹理图片。下面是一个中国人在第二人生里扮演的角色，很有特色的，如下图：

蔡军生 QQ:9073204 深圳