fixing some problems,

trying to draw instanced,
now it crashes

MshViewer/Source/OpenGlController.cpp

@@ -92,15 +92,27 @@ void OpenGLController::processInit()
 	glBindBuffer(GL_ARRAY_BUFFER, 0);
 
 	glBindBuffer(GL_ARRAY_BUFFER, gluiInstanceBufferID);
-	glVertexAttribPointer(2, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GL_FLOAT) * 0));
-	glVertexAttribPointer(3, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GL_FLOAT) * 4));
-	glVertexAttribPointer(4, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GL_FLOAT) * 8));
-	glVertexAttribPointer(5, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GL_FLOAT) * 12));
+	glVertexAttribPointer(2, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GLfloat) * 0));
+	glVertexAttribPointer(3, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GLfloat) * 4));
+	glVertexAttribPointer(4, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GLfloat) * 8));
+	glVertexAttribPointer(5, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GLfloat) * 12));
 	glBindBuffer(GL_ARRAY_BUFFER, 0);
 
+	// enable position, UV and mvp
 	glEnableVertexAttribArray(0);
 	glEnableVertexAttribArray(1);
 
+	glEnableVertexAttribArray(2);
+	glEnableVertexAttribArray(3);
+	glEnableVertexAttribArray(4);
+	glEnableVertexAttribArray(5);
+
+	// MPV only once per instance
+	glVertexAttribDivisor(2, 1);
+	glVertexAttribDivisor(3, 1);
+	glVertexAttribDivisor(4, 1);
+	glVertexAttribDivisor(5, 1);
+
 	// get the painter ready
 	try
 	{
@@ -251,10 +263,13 @@ void OpenGLController::updateScene()
 	// use shader prgm
 	glUseProgram(gluiShaderPrgmID);
 
-	// tell shader transformation
-	//glUniformMatrix4fv(gluiMatrixID, 1, GL_FALSE, &getMVPMatrix()[0][0]);
+	// fill vector with MVPs of all Models (only 1 for testing)
+	std::vector<glm::mat4> mvpMatrices;
+	mvpMatrices.push_back(getMVPMatrix());
+
+	// give the MVPs to the shader
 	glBindBuffer(GL_UNIFORM_BUFFER, gluiInstanceBufferID);
-	glBufferData(GL_UNIFORM_BUFFER, sizeof(glm::mat4) * 1, NULL, GL_STREAM_DRAW);
+	glBufferSubData(GL_UNIFORM_BUFFER, sizeof(glm::mat4) * mvpMatrices.size(), NULL, mvpMatrices.data());
 	glBindBuffer(GL_UNIFORM_BUFFER, 0);
 
 	// bind texture in texture unit 0
@@ -263,8 +278,8 @@ void OpenGLController::updateScene()
 	// tell sampler to use texture unit 0
 	glUniform1i(gluiSamplerID, 0);
 
-	//draw objects
-	glDrawArrays(GL_TRIANGLES, 0, vModels.front()->meshSize);
+	//draw objects hardcoded only 1 instance for testing
+	glDrawArraysInstanced(GL_TRIANGLES, 0, vModels.front()->meshSize, 1);
 
 	glfwSwapBuffers(pWindow);
 	glfwPollEvents();