GLUSvoid reshape(GLUSint width, GLUSint height)
{
GLfloat modelMatrix[16];
GLfloat normalMatrix[9];
GLfloat viewMatrix[16];
GLfloat modelViewProjectionMatrix[16];
glViewport(0, 0, width, height);
// Initialize with the identity matrix ...
glusMatrix4x4Identityf(modelMatrix);
// ... and rotate the cube at two axes that we do see some sides.
glusMatrix4x4RotateRzRxRyf(modelMatrix, 0.0f, 45.0f, 45.0f);
// This model matrix is a rigid body transform. So no need for the inverse, transposed matrix.
glusMatrix4x4ExtractMatrix3x3f(normalMatrix, modelMatrix);
glusMatrix4x4Perspectivef(modelViewProjectionMatrix, 40.0f, (GLfloat) width / (GLfloat) height, 1.0f, 100.0f);
glusMatrix4x4LookAtf(viewMatrix, 0.0f, 0.0f, 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);
// Here we create the view projection matrix ...
glusMatrix4x4Multiplyf(modelViewProjectionMatrix, modelViewProjectionMatrix, viewMatrix);
// ... and now the final model view projection matrix.
glusMatrix4x4Multiplyf(modelViewProjectionMatrix, modelViewProjectionMatrix, modelMatrix);
glUniformMatrix4fv(g_modelViewProjectionMatrixLocation, 1, GL_FALSE, modelViewProjectionMatrix);
// Set the normal matrix.
glUniformMatrix3fv(g_normalMatrixLocation, 1, GL_FALSE, normalMatrix);
}
GLUSboolean update(GLUSfloat time)
{
// Angle for rotation
static GLfloat angle = 0.0f;
// Matrix for the model
GLfloat modelViewMatrix[16];
GLfloat normalMatrix[9];
GLfloat viewMatrix[9];
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// Calculate the model matrix ...
glusMatrix4x4Identityf(modelViewMatrix);
// ... by finally rotating the cube.
glusMatrix4x4RotateRzRxRyf(modelViewMatrix, 0.0f, 15.0f, angle);
// Create the model view matrix.
glusMatrix4x4Multiplyf(modelViewMatrix, g_viewMatrix, modelViewMatrix);
// Again, extract the normal matrix. Remember, so far the model view matrix (rotation part) is orthogonal.
glusMatrix4x4ExtractMatrix3x3f(normalMatrix, modelViewMatrix);
glUniformMatrix4fv(g_modelViewMatrixLocation, 1, GL_FALSE, modelViewMatrix);
glUniformMatrix3fv(g_normalMatrixLocation, 1, GL_FALSE, normalMatrix);
//
// Extract the rotation part of the view matrix.
glusMatrix4x4ExtractMatrix3x3f(viewMatrix, g_viewMatrix);
// Pass this matrix to the shader with the transpose flag. As the view matrix is orthogonal, the transposed is the inverse view matrix.
glUniformMatrix3fv(g_inverseViewMatrixLocation, 1, GL_TRUE, viewMatrix);
//
glDrawElements(GL_TRIANGLES, g_numberIndicesSphere, GL_UNSIGNED_INT, 0);
angle += 20.0f * time;
return GLUS_TRUE;
}
GLUSboolean update(GLUSfloat time)
{
static GLfloat angle = 0.0f;
GLfloat modelMatrix[16];
GLfloat normalMatrix[9];
// 90 degrees per second. Rotate the texture cube along the y axis (yaw).
angle += 90.0f * time;
glusMatrix4x4Identityf(modelMatrix);
glusMatrix4x4RotateRzRxRyf(modelMatrix, 0.0f, 45.0f, angle);
glUniformMatrix4fv(g_modelMatrixLocation, 1, GL_FALSE, modelMatrix);
// Model matrix is a rigid body matrix.
glusMatrix4x4ExtractMatrix3x3f(normalMatrix, modelMatrix);
glUniformMatrix3fv(g_normalMatrixLocation, 1, GL_FALSE, normalMatrix);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glDrawElements(GL_TRIANGLES, g_numberIndicesSphere, GL_UNSIGNED_INT, 0);
return GLUS_TRUE;
}
GLUSboolean update(GLUSfloat time)
{
static GLfloat angle = 0.0f;
GLfloat modelViewMatrix[16];
GLfloat viewMatrix[16];
GLfloat modelMatrix[16];
GLfloat normalMatrix[9];
// Render the scene.
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
glUseProgram(g_program.program);
glusLookAtf(viewMatrix, g_cameraPosition[0], g_cameraPosition[1], g_cameraPosition[2], 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);
glUniformMatrix4fv(g_viewMatrixLocation, 1, GL_FALSE, viewMatrix);
// Draw Color
glEnable(GL_CULL_FACE);
glEnable(GL_DEPTH_TEST);
// Plane
glusMatrix4x4Identityf(modelMatrix);
glusMatrix4x4Translatef(modelMatrix, 0.0f, 0.0f, -5.0f);
glusMatrix4x4Multiplyf(modelViewMatrix, viewMatrix, modelMatrix);
glusMatrix4x4ExtractMatrix3x3f(normalMatrix, modelViewMatrix);
glUniformMatrix4fv(g_modelMatrixLocation, 1, GL_FALSE, modelMatrix);
glUniformMatrix3fv(g_normalMatrixLocation, 1, GL_FALSE, normalMatrix);
glUniform4f(g_colorLocation, 0.0f, 0.5f, 0.0f, 1.0f);
glBindVertexArray(g_vaoPlane);
glDrawElements(GL_TRIANGLES, g_numberIndicesPlane, GL_UNSIGNED_INT, 0);
// Torus
glusMatrix4x4Identityf(modelMatrix);
glusMatrix4x4RotateRzRxRyf(modelMatrix, 0.0f, 0.0f, angle);
glusMatrix4x4Multiplyf(modelViewMatrix, viewMatrix, modelMatrix);
glusMatrix4x4ExtractMatrix3x3f(normalMatrix, modelViewMatrix);
glUniformMatrix4fv(g_modelMatrixLocation, 1, GL_FALSE, modelMatrix);
glUniformMatrix3fv(g_normalMatrixLocation, 1, GL_FALSE, normalMatrix);
glUniform4f(g_colorLocation, 0.33f, 0.0f, 0.5f, 1.0f);
glBindVertexArray(g_vao);
glDrawElements(GL_TRIANGLES_ADJACENCY, g_numberIndices, GL_UNSIGNED_INT, 0);
// Draw Shadow Volume
// Using zfail see http://joshbeam.com/articles/stenciled_shadow_volumes_in_opengl/
glEnable(GL_STENCIL_TEST);
glUseProgram(g_programShadowVolume.program);
glUniformMatrix4fv(g_viewMatrixShadowVolumeLocation, 1, GL_FALSE, viewMatrix);
glUniformMatrix4fv(g_modelMatrixShadowVolumeLocation, 1, GL_FALSE, modelMatrix);
// Only render to the stencil buffer
glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
glDepthMask(GL_FALSE);
// Avoid ugly artifacts
glEnable(GL_POLYGON_OFFSET_FILL);
// Needed, as vertices in the back are extruded to infinity
glEnable(GL_DEPTH_CLAMP);
glBindVertexArray(g_vaoShadowVolume);
// Render the back faces ...
glCullFace(GL_FRONT);
glStencilFunc(GL_ALWAYS, 0x0, 0xff);
glStencilOp(GL_KEEP, GL_INCR, GL_KEEP);
glDrawElements(GL_TRIANGLES_ADJACENCY, g_numberIndices, GL_UNSIGNED_INT, 0);
// ... and then the front faces
glCullFace(GL_BACK);
glStencilFunc(GL_ALWAYS, 0x0, 0xff);
glStencilOp(GL_KEEP, GL_DECR, GL_KEEP);
glDrawElements(GL_TRIANGLES_ADJACENCY, g_numberIndices, GL_UNSIGNED_INT, 0);
// Reset
glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
glDepthMask(GL_TRUE);
glDisable(GL_POLYGON_OFFSET_FILL);
glDisable(GL_DEPTH_CLAMP);
// Draw shadow by blending a black, half transparent plane
glUseProgram(g_programShadowPlane.program);
glDisable(GL_DEPTH_TEST);
glEnable(GL_BLEND);
// Only render, where the stencil buffer is not 0
glStencilFunc(GL_NOTEQUAL, 0x0, 0xff);
glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
glBindVertexArray(g_vaoShadowPlane);
glDrawElements(GL_TRIANGLES, g_numberIndicesShadowPlane, GL_UNSIGNED_INT, 0);
glDisable(GL_BLEND);
glDisable(GL_STENCIL_TEST);
//
angle += 20.0f * time;
return GLUS_TRUE;
}
GLUSboolean update(GLUSfloat time)
{
static GLfloat angle = 0.0f;
GLfloat modelViewMatrix[16];
GLfloat viewMatrix[16];
GLfloat shadowProjectionMatrix[16];
GLfloat modelMatrix[16];
GLfloat normalMatrix[9];
// This shadow plane represents mathematically the background plane
GLfloat shadowPlane[4] = {0.0f, 0.0f, 1.0f, 5.0f};
glusMatrix4x4LookAtf(viewMatrix, g_cameraPosition[0], g_cameraPosition[1], g_cameraPosition[2], 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
//
// Render the scene.
//
glUseProgram(g_program.program);
glUniformMatrix4fv(g_viewMatrixLocation, 1, GL_FALSE, viewMatrix);
// Background Plane
glusMatrix4x4Identityf(modelMatrix);
glusMatrix4x4Translatef(modelMatrix, 0.0f, 0.0f, -5.0f);
glusMatrix4x4Multiplyf(modelViewMatrix, viewMatrix, modelMatrix);
glusMatrix4x4ExtractMatrix3x3f(normalMatrix, modelViewMatrix);
glUniformMatrix4fv(g_modelMatrixLocation, 1, GL_FALSE, modelMatrix);
glUniformMatrix3fv(g_normalMatrixLocation, 1, GL_FALSE, normalMatrix);
glUniform4f(g_colorLocation, 0.0f, 0.5f, 0.0f, 1.0f);
glBindVertexArray(g_vaoBackground);
glDrawElements(GL_TRIANGLES, g_numberIndicesBackground, GL_UNSIGNED_INT, 0);
//
// Render the planar shadow
//
glUseProgram(g_programShadow.program);
glUniformMatrix4fv(g_viewMatrixShadowLocation, 1, GL_FALSE, viewMatrix);
// Torus projected as a shadow
glusMatrix4x4PlanarShadowDirectionalLightf(shadowProjectionMatrix, shadowPlane, g_lightDirection);
glUniformMatrix4fv(g_shadowProjectionMatrixShadowLocation, 1, GL_FALSE, shadowProjectionMatrix);
glusMatrix4x4Identityf(modelMatrix);
glusMatrix4x4RotateRzRxRyf(modelMatrix, 0.0f, 0.0f, angle);
glUniformMatrix4fv(g_modelMatrixShadowLocation, 1, GL_FALSE, modelMatrix);
glBindVertexArray(g_vaoShadow);
// Overwrite the background plane
glDisable(GL_DEPTH_TEST);
glDrawElements(GL_TRIANGLES, g_numberIndicesTorus, GL_UNSIGNED_INT, 0);
glEnable(GL_DEPTH_TEST);
// Torus with color
glUseProgram(g_program.program);
glusMatrix4x4Multiplyf(modelViewMatrix, viewMatrix, modelMatrix);
glusMatrix4x4ExtractMatrix3x3f(normalMatrix, modelViewMatrix);
glUniformMatrix4fv(g_modelMatrixLocation, 1, GL_FALSE, modelMatrix);
glUniformMatrix3fv(g_normalMatrixLocation, 1, GL_FALSE, normalMatrix);
glUniform4f(g_colorLocation, 0.33f, 0.0f, 0.5f, 1.0f);
glBindVertexArray(g_vao);
glDrawElements(GL_TRIANGLES, g_numberIndicesTorus, GL_UNSIGNED_INT, 0);
//
angle += 20.0f * time;
return GLUS_TRUE;
}
GLUSboolean update(GLUSfloat time)
{
static GLfloat angle = 0.0f;
GLfloat shadowMatrix[16];
GLfloat modelViewMatrix[16];
GLfloat viewMatrix[16];
GLfloat modelMatrix[16];
GLfloat normalMatrix[9];
// Rendering into the shadow texture.
glBindTexture(GL_TEXTURE_2D, 0);
// Setup for the framebuffer.
glBindFramebuffer(GL_FRAMEBUFFER, g_fbo);
glViewport(0, 0, g_shadowTextureSize, g_shadowTextureSize);
glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
glusMatrix4x4LookAtf(viewMatrix, g_lightPosition[0], g_lightPosition[1], g_lightPosition[2], 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);
glusMatrix4x4Multiplyf(shadowMatrix, g_shadowMatrix, viewMatrix);
glClear(GL_DEPTH_BUFFER_BIT);
glUseProgram(g_programShadow.program);
// Render the torus.
glusMatrix4x4Identityf(modelMatrix);
glusMatrix4x4RotateRzRxRyf(modelMatrix, 0.0f, 0.0f, angle);
glusMatrix4x4Multiplyf(modelViewMatrix, viewMatrix, modelMatrix);
glUniformMatrix4fv(g_modelViewMatrixShadowLocation, 1, GL_FALSE, modelViewMatrix);
glBindVertexArray(g_vaoShadow);
glEnable(GL_POLYGON_OFFSET_FILL);
glFrontFace(GL_CW);
glDrawElements(GL_TRIANGLES, g_numberIndicesSphere, GL_UNSIGNED_INT, 0);
glDisable(GL_POLYGON_OFFSET_FILL);
glFrontFace(GL_CCW);
// Revert for the scene.
glBindFramebuffer(GL_FRAMEBUFFER, 0);
glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
glViewport(0, 0, g_width, g_height);
glBindTexture(GL_TEXTURE_2D, g_shadowTexture);
//
// Render the scene.
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glUseProgram(g_program.program);
glusMatrix4x4LookAtf(viewMatrix, g_cameraPosition[0], g_cameraPosition[1], g_cameraPosition[2], 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);
glUniformMatrix4fv(g_viewMatrixLocation, 1, GL_FALSE, viewMatrix);
glUniformMatrix4fv(g_shadowMatrixLocation, 1, GL_FALSE, shadowMatrix);
// Plane
glusMatrix4x4Identityf(modelMatrix);
glusMatrix4x4Translatef(modelMatrix, 0.0f, 0.0f, -5.0f);
glusMatrix4x4Multiplyf(modelViewMatrix, viewMatrix, modelMatrix);
glusMatrix4x4ExtractMatrix3x3f(normalMatrix, modelViewMatrix);
glUniformMatrix4fv(g_modelMatrixLocation, 1, GL_FALSE, modelMatrix);
glUniformMatrix3fv(g_normalMatrixLocation, 1, GL_FALSE, normalMatrix);
glUniform4f(g_colorLocation, 0.0f, 0.5f, 0.0f, 1.0f);
glBindVertexArray(g_vaoBackground);
glDrawElements(GL_TRIANGLES, g_numberIndicesBackground, GL_UNSIGNED_INT, 0);
// Torus
glusMatrix4x4Identityf(modelMatrix);
glusMatrix4x4RotateRzRxRyf(modelMatrix, 0.0f, 0.0f, angle);
glusMatrix4x4Multiplyf(modelViewMatrix, viewMatrix, modelMatrix);
glusMatrix4x4ExtractMatrix3x3f(normalMatrix, modelViewMatrix);
glUniformMatrix4fv(g_modelMatrixLocation, 1, GL_FALSE, modelMatrix);
glUniformMatrix3fv(g_normalMatrixLocation, 1, GL_FALSE, normalMatrix);
glUniform4f(g_colorLocation, 0.33f, 0.0f, 0.5f, 1.0f);
glBindVertexArray(g_vao);
glDrawElements(GL_TRIANGLES, g_numberIndicesSphere, GL_UNSIGNED_INT, 0);
//
angle += 20.0f * time;
return GLUS_TRUE;
}
GLUSboolean update(GLUSfloat time)
{
static GLfloat angle = 0.0f;
GLfloat depthPassMatrix[16];
GLfloat modelViewMatrix[16];
GLfloat viewMatrix[16];
GLfloat modelMatrix[16];
GLfloat normalMatrix[9];
// Rendering into the depth pass texture.
glBindTexture(GL_TEXTURE_2D, 0);
// Setup for the framebuffer.
glBindFramebuffer(GL_FRAMEBUFFER, g_fbo);
glViewport(0, 0, g_depthPassTextureSize, g_depthPassTextureSize);
glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
glusMatrix4x4LookAtf(viewMatrix, g_lightPosition[0], g_lightPosition[1], g_lightPosition[2], 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);
glusMatrix4x4Multiplyf(depthPassMatrix, g_depthPassMatrix, viewMatrix);
glClear(GL_DEPTH_BUFFER_BIT);
glUseProgram(g_programDepthPass.program);
// Render the Dragon.
glusMatrix4x4Identityf(modelMatrix);
glusMatrix4x4RotateRzRxRyf(modelMatrix, 0.0f, 0.0f, angle);
// Upscaling a little bit avoids artifacts.
glusMatrix4x4Scalef(modelMatrix, 1.05f, 1.05f, 1.05f);
glusMatrix4x4Multiplyf(modelViewMatrix, viewMatrix, modelMatrix);
glUniformMatrix4fv(g_modelViewMatrixDepthPassLocation, 1, GL_FALSE, modelViewMatrix);
glBindVertexArray(g_vaoDepthPass);
glDrawArrays(GL_TRIANGLES, 0, g_numberVertices);
// Revert for the scene.
glBindFramebuffer(GL_FRAMEBUFFER, 0);
glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
glViewport(0, 0, g_width, g_height);
glBindTexture(GL_TEXTURE_2D, g_depthPassTexture);
//
// Render the scene.
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glUseProgram(g_program.program);
glusMatrix4x4LookAtf(viewMatrix, g_cameraPosition[0], g_cameraPosition[1], g_cameraPosition[2], 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);
glUniformMatrix4fv(g_viewMatrixLocation, 1, GL_FALSE, viewMatrix);
glUniformMatrix4fv(g_depthPassMatrixLocation, 1, GL_FALSE, depthPassMatrix);
// Dragon
glusMatrix4x4Identityf(modelMatrix);
glusMatrix4x4RotateRzRxRyf(modelMatrix, 0.0f, 0.0f, angle);
glusMatrix4x4Multiplyf(modelViewMatrix, viewMatrix, modelMatrix);
glusMatrix4x4ExtractMatrix3x3f(normalMatrix, modelViewMatrix);
glUniformMatrix4fv(g_modelMatrixLocation, 1, GL_FALSE, modelMatrix);
glUniformMatrix3fv(g_normalMatrixLocation, 1, GL_FALSE, normalMatrix);
glUniform4f(g_diffuseColorLocation, 0.8f, 0.0f, 0.0f, 1.0f);
glUniform4f(g_scatterColorLocation, 0.8f, 0.8f, 0.0f, 1.0f);
glUniform2f(g_nearFarLocation, g_near, g_far);
glUniform1f(g_wrapLocation, g_wrap);
glUniform1f(g_scatterWidthLocation, g_scatterWidth);
glUniform1f(g_scatterFalloffLocation, g_scatterFalloff);
glBindVertexArray(g_vao);
glDrawArrays(GL_TRIANGLES, 0, g_numberVertices);
//
angle += 20.0f * time;
return GLUS_TRUE;
}