Set the perspective projection for projective texture mapping. Change the demo to two bears with the same view projection matrix for the camera and the projector.

data/teddy_large.urdf

@@ -0,0 +1,32 @@
+<?xml version="0.0" ?>
+<robot name="cube.urdf">
+  <link name="baseLink">
+    <contact>
+      <lateral_friction value="0.5"/>
+      <rolling_friction value="0.0"/>
+      <contact_cfm value="0.0"/>
+      <contact_erp value="1.0"/>
+    </contact>
+    <inertial>
+      <origin rpy="0 0 0" xyz="0.07 0.05 0.03"/>
+       <mass value=".1"/>
+       <inertia ixx="1" ixy="0" ixz="0" iyy="1" iyz="0" izz="1"/>
+    </inertial>
+    <visual>
+      <origin rpy="0 0 0" xyz="0 0 0"/>
+      <geometry>
+        <mesh filename="teddy2_VHACD_CHs.obj" scale="3 3 3"/>
+      </geometry>
+       <material name="red">
+        <color rgba="1 1 1 1"/>
+      </material>
+    </visual>
+    <collision>
+      <origin rpy="0 0 0" xyz="0 0 0"/>
+      <geometry>
+	 	<mesh filename="teddy2_VHACD_CHs.obj" scale="3 3 3"/>
+      </geometry>
+    </collision>
+  </link>
+</robot>
+

data/teddy_vhacd.urdf

@@ -29,4 +29,3 @@
     </collision>
   </link>
 </robot>
-

examples/OpenGLWindow/GLInstancingRenderer.cpp

@@ -17,7 +17,6 @@ subject to the following restrictions:
 
 ///todo: make this configurable in the gui
 bool useShadowMap = true;// true;//false;//true;
-float projectiveTextureViewSize = 10;
 bool useProjectiveTexture = false;
 int shadowMapWidth= 4096;
 int shadowMapHeight= 4096;
@@ -228,9 +227,6 @@ struct InternalDataRenderer : public GLInstanceRendererInternalData
 
 	b3Vector3 m_lightPos;
 	b3Vector3 m_lightSpecularIntensity;
-	
-	b3Vector3 m_projectorPos;
-	b3Vector3 m_projectorDir;
 
 	GLuint				m_defaultTexturehandle;
 	b3AlignedObjectArray<InternalTextureHandle>	m_textureHandles;
@@ -252,8 +248,6 @@ struct InternalDataRenderer : public GLInstanceRendererInternalData
 	{
 		m_lightPos=b3MakeVector3(-50,30,40);
 		m_lightSpecularIntensity.setValue(1,1,1);
-		
-		m_projectorPos=b3MakeVector3(-50,30,40);
 
 		//clear to zero to make it obvious if the matrix is used uninitialized
 		for (int i=0;i<16;i++)
@@ -336,7 +330,7 @@ static GLint	projectiveTexture_cameraPositionIn = 0;
 static GLint	projectiveTexture_materialShininessIn = 0;
 
 static GLint	projectiveTexture_ProjectionMatrix=0;
-static GLint	projectiveTexture_DepthBiasModelViewMatrix=0;
+static GLint	projectiveTexture_TextureMVP=0;
 static GLint    projectiveTexture_uniform_texture_diffuse = 0;
 static GLint	projectiveTexture_shadowMap = 0;
 
@@ -1241,7 +1235,7 @@ void GLInstancingRenderer::InitShaders()
 	projectiveTexture_materialSpecularColor = glGetUniformLocation(projectiveTextureInstancingShader, "materialSpecularColorIn");
 	projectiveTexture_MVP = 		glGetUniformLocation(projectiveTextureInstancingShader, "MVP");
 	projectiveTexture_ProjectionMatrix = glGetUniformLocation(projectiveTextureInstancingShader, "ProjectionMatrix");
-	projectiveTexture_DepthBiasModelViewMatrix = glGetUniformLocation(projectiveTextureInstancingShader, "DepthBiasModelViewProjectionMatrix");
+	projectiveTexture_TextureMVP = glGetUniformLocation(projectiveTextureInstancingShader, "TextureMVP");
 	projectiveTexture_uniform_texture_diffuse = glGetUniformLocation(projectiveTextureInstancingShader, "Diffuse");
 	projectiveTexture_shadowMap = glGetUniformLocation(projectiveTextureInstancingShader,"shadowMap");
 	projectiveTexture_lightPosIn = glGetUniformLocation(projectiveTextureInstancingShader,"lightPosIn");
@@ -2168,17 +2162,9 @@ void GLInstancingRenderer::renderSceneInternal(int orgRenderMode)
 	GLfloat depthBiasMVP[4][4];
 	b3Matrix4x4Mul(biasMatrix,depthMVP,depthBiasMVP);
 
-	// Compute projection matrix for texture projector
+	// TODO: Expose the projective texture matrix setup. Temporarily set it to be the same as camera view projection matrix.
-	float textureViewMatrix[4][4];
+	GLfloat textureMVP[16];
-	b3Vector3 projectorDir = m_data->m_projectorDir.normalize();
+	b3Matrix4x4Mul16(m_data->m_projectionMatrix,m_data->m_viewMatrix,textureMVP);
-	float projectorDist = 0;
-	b3CreateLookAt(m_data->m_projectorPos,center,up, &textureViewMatrix[0][0]);
-	GLfloat textureModelMatrix[4][4];
-	b3CreateDiagonalMatrix(1.f, textureModelMatrix);
-	b3Matrix4x4Mul(textureViewMatrix, textureModelMatrix, textureModelViewMatrix);
-	b3CreateOrtho(-projectiveTextureViewSize,projectiveTextureViewSize,-projectiveTextureViewSize,projectiveTextureViewSize,1,300,textureProjectionMatrix);
-	GLfloat textureMVP[4][4];
-	b3Matrix4x4Mul(textureProjectionMatrix, textureModelViewMatrix, textureMVP);
 
 	//float m_frustumZNear=0.1;
     //float m_frustumZFar=100.f;
@@ -2576,10 +2562,7 @@ b3Assert(glGetError() ==GL_NO_ERROR);
 								glUniform3f(projectiveTexture_cameraPositionIn,camPos[0],camPos[1],camPos[2]);
 								glUniform1f(projectiveTexture_materialShininessIn,gfxObj->m_materialShinyNess);
 								
-								glUniformMatrix4fv(projectiveTexture_DepthBiasModelViewMatrix, 1, false, &textureMVP[0][0]);
+								glUniformMatrix4fv(projectiveTexture_TextureMVP, 1, false, &textureMVP[0]);
-								glActiveTexture(GL_TEXTURE1);
-								glBindTexture(GL_TEXTURE_2D, m_data->m_shadowTexture);
-								glUniform1i(projectiveTexture_shadowMap,1);
 								
 								//sort transparent objects
 								if ( gfxObj->m_flags&eGfxTransparency)
@@ -2600,8 +2583,6 @@ b3Assert(glGetError() ==GL_NO_ERROR);
 									glDisable (GL_BLEND);
 									glDepthMask(true);
 								}
-								glActiveTexture(GL_TEXTURE1);
-								glBindTexture(GL_TEXTURE_2D,0);
 								
 								glActiveTexture(GL_TEXTURE0);
 								glBindTexture(GL_TEXTURE_2D,0);

examples/OpenGLWindow/Shaders/projectiveTextureInstancingVS.glsl

@@ -11,7 +11,7 @@ layout (location = 5) in vec4 instance_color;
 layout (location = 6) in vec3 instance_scale;
 
 
-uniform mat4 DepthBiasModelViewProjectionMatrix;
+uniform mat4 TextureMVP;
 uniform mat4 MVP;
 uniform vec3 lightPosIn;
 uniform vec3 cameraPositionIn;
@@ -93,7 +93,7 @@ void main(void)
 	gl_Position = vertexLoc;
 
 	fragment.color = instance_color;
-	vec4 projcoords = DepthBiasModelViewProjectionMatrix * vec4((instance_position+localcoord).xyz,1);
+	vec4 projcoords = TextureMVP * vec4((instance_position+localcoord).xyz,1);
-	vert.texcoord = projcoords.xy;
+	vert.texcoord = projcoords.xy/projcoords.z;
 }
 

examples/OpenGLWindow/Shaders/projectiveTextureInstancingVS.h

@@ -9,7 +9,7 @@ static const char* projectiveTextureInstancingVertexShader= \
 "layout (location = 4) in vec3 vertexnormal;\n"
 "layout (location = 5) in vec4 instance_color;\n"
 "layout (location = 6) in vec3 instance_scale;\n"
-"uniform mat4 DepthBiasModelViewProjectionMatrix;\n"
+"uniform mat4 TextureMVP;\n"
 "uniform mat4 MVP;\n"
 "uniform vec3 lightPosIn;\n"
 "uniform vec3 cameraPositionIn;\n"
@@ -80,7 +80,7 @@ static const char* projectiveTextureInstancingVertexShader= \
 "	vec4 vertexLoc = MVP* vec4((instance_position+localcoord).xyz,1);\n"
 "	gl_Position = vertexLoc;\n"
 "	fragment.color = instance_color;\n"
-"	vec4 projcoords = DepthBiasModelViewProjectionMatrix * vec4((instance_position+localcoord).xyz,1);\n"
+"	vec4 projcoords = TextureMVP * vec4((instance_position+localcoord).xyz,1);\n"
-"	vert.texcoord = projcoords.xy;\n"
+"	vert.texcoord = projcoords.xy/projcoords.z;\n"
 "}\n"
 ;

examples/pybullet/examples/projective_texture.py

@@ -6,34 +6,17 @@ import numpy as np
 
 physicsClient = p.connect(p.GUI)
 
-p.setGravity(0,0,-10)
+p.setGravity(0,0,0)
-planeId = p.loadURDF("plane.urdf")
+bearStartPos1 = [-3.3,0,0]
-cubeStartPos = [0,0,1]
+bearStartOrientation1 = p.getQuaternionFromEuler([0,0,0])
-cubeStartOrientation = p.getQuaternionFromEuler([0,0,0])
+bearId1 = p.loadURDF("teddy_large.urdf", bearStartPos1, bearStartOrientation1)
-boxId = p.loadURDF("cube.urdf",cubeStartPos, cubeStartOrientation)
+bearStartPos2 = [0,0,0]
-cubePos, cubeOrn = p.getBasePositionAndOrientation(boxId)
+bearStartOrientation2 = p.getQuaternionFromEuler([0,0,0])
-textureId = p.loadTexture("checker_blue.png")
+bearId2 = p.loadURDF("teddy_large.urdf",bearStartPos2, bearStartOrientation2)
+textureId = p.loadTexture("checker_grid.jpg")
 p.changeVisualShape(objectUniqueId=0, linkIndex=-1, textureUniqueId=textureId)
 p.changeVisualShape(objectUniqueId=1, linkIndex=-1, textureUniqueId=textureId)
 
-fov = 70
-pixelWidth = 640
-pixelHeight = 512
-aspect = pixelWidth / pixelHeight;
-nearPlane = 0.01
-farPlane = 100
-projectionMatrix = p.computeProjectionMatrixFOV(fov, aspect, nearPlane, farPlane);
-viewMatrixLeft = p.computeViewMatrix(cameraEyePosition=[0.045, 3.0, 3.0], cameraTargetPosition=[0.045,0,0], cameraUpVector=[0,0,1])
-viewMatrixRight = p.computeViewMatrix(cameraEyePosition=[-0.045, 3.0, 3.0], cameraTargetPosition=[-0.045,0,0], cameraUpVector=[0,0,1])
-leftImage = p.getCameraImage(width=640,height=512,viewMatrix=viewMatrixLeft,projectionMatrix=projectionMatrix,renderer=p.ER_BULLET_HARDWARE_OPENGL)
-rightImage = p.getCameraImage(width=640,height=512,viewMatrix=viewMatrixRight,projectionMatrix=projectionMatrix,renderer=p.ER_BULLET_HARDWARE_OPENGL)
-
-left_img = np.reshape(np.asarray(leftImage[2], dtype=np.float32), (512, 640, 4))
-left_img /= 255
-plt.imsave("left_image.png", left_img)
-right_img = np.reshape(np.asarray(rightImage[2], dtype=np.float32), (512, 640, 4))
-right_img /= 255
-plt.imsave("right_image.png", right_img)
 
 useRealTimeSimulation = 1
 
@@ -42,7 +25,7 @@ if (useRealTimeSimulation):
 
 while 1:
 	if (useRealTimeSimulation):
-		p.setGravity(0,0,-10)
+		p.setGravity(0,0,0)
 		sleep(0.01) # Time in seconds.
 	else:
 		p.stepSimulation()