#include "R3DScrollFog.h" #include "Graphics/Shader.h" #include "Mat4.h" namespace New3D { static const char *vertexShaderFog = R"glsl( uniform mat4 mvp; void main(void) { gl_Position = mvp * gl_Vertex; }; )glsl"; static const char *fragmentShaderFog = R"glsl( uniform float fogAttenuation; uniform float fogAmbient; uniform vec4 fogColour; uniform vec3 spotFogColor; uniform vec4 spotEllipse; // Spotlight on fog float ellipse; vec2 position, size; vec3 lSpotFogColor; // Scroll fog float lfogAttenuation; vec3 lFogColor; vec4 scrollFog; void main() { // Scroll fog base color lFogColor = fogColour.rgb * fogAmbient; // Spotlight on fog (area) position = spotEllipse.xy; size = spotEllipse.zw; ellipse = length((gl_FragCoord.xy - position) / size); ellipse = pow(ellipse, 2.0); // decay rate = square of distance from center ellipse = 1.0 - ellipse; // invert ellipse = max(0.0, ellipse); // clamp // Spotlight on fog (color) lSpotFogColor = mix(spotFogColor * ellipse * fogColour.rgb, vec3(0.0), fogAttenuation); // Scroll fog density scrollFog = vec4(lFogColor + lSpotFogColor, fogColour.a); // Final Color gl_FragColor = scrollFog; }; )glsl"; R3DScrollFog::R3DScrollFog() { //default coordinates are NDC -1,1 etc m_triangles[0].p1.Set(-1,-1, 0); m_triangles[0].p2.Set(-1, 1, 0); m_triangles[0].p3.Set( 1, 1, 0); m_triangles[1].p1.Set(-1,-1, 0); m_triangles[1].p2.Set( 1, 1, 0); m_triangles[1].p3.Set( 1,-1, 0); m_shaderProgram = 0; m_vertexShader = 0; m_fragmentShader = 0; AllocResources(); } R3DScrollFog::~R3DScrollFog() { DeallocResources(); } void R3DScrollFog::DrawScrollFog(float rgba[4], float attenuation, float ambient, float *spotRGB, float *spotEllipse) { //======= Mat4 mvp; //======= // yeah this would have been much easier with immediate mode and fixed function .. >_< // some ogl states glDepthMask (GL_FALSE); // disable z writes glDisable (GL_DEPTH_TEST); // disable depth testing glEnable (GL_BLEND); glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); m_vbo.Bind (true); glUseProgram (m_shaderProgram); glUniform4f (m_locFogColour, rgba[0], rgba[1], rgba[2], rgba[3]); glUniform1f (m_locFogAttenuation, attenuation); glUniform1f (m_locFogAmbient, ambient); glUniform3f (m_locSpotFogColor, spotRGB[0], spotRGB[1], spotRGB[2]); glUniform4f (m_locSpotEllipse, spotEllipse[0], spotEllipse[1], spotEllipse[2], spotEllipse[3]); glUniformMatrix4fv (m_locMVP, 1, GL_FALSE, mvp); glEnableClientState (GL_VERTEX_ARRAY); glVertexPointer (3, GL_FLOAT, sizeof(SFVertex), 0); glDrawArrays (GL_TRIANGLES, 0, 6); glDisableClientState(GL_VERTEX_ARRAY); glUseProgram (0); m_vbo.Bind (false); glDisable (GL_BLEND); glDepthMask (GL_TRUE); } void R3DScrollFog::AllocResources() { bool success = LoadShaderProgram(&m_shaderProgram, &m_vertexShader, &m_fragmentShader, std::string(), std::string(), vertexShaderFog, fragmentShaderFog); m_locMVP = glGetUniformLocation(m_shaderProgram, "mvp"); m_locFogColour = glGetUniformLocation(m_shaderProgram, "fogColour"); m_locFogAttenuation = glGetUniformLocation(m_shaderProgram, "fogAttenuation"); m_locFogAmbient = glGetUniformLocation(m_shaderProgram, "fogAmbient"); m_locSpotFogColor = glGetUniformLocation(m_shaderProgram, "spotFogColor"); m_locSpotEllipse = glGetUniformLocation(m_shaderProgram, "spotEllipse"); m_vbo.Create(GL_ARRAY_BUFFER, GL_STATIC_DRAW, sizeof(SFTriangle) * (2), m_triangles); } void R3DScrollFog::DeallocResources() { if (m_shaderProgram) { DestroyShaderProgram(m_shaderProgram, m_vertexShader, m_fragmentShader); } m_shaderProgram = 0; m_vertexShader = 0; m_fragmentShader = 0; m_vbo.Destroy(); } }