#define NQ 1
GLuint bbTexIds[NQ];
+// Stores attenuation ratio inside r channel
+// Should be highest value at center
void precalculateBillboardTextures() {
float data[32 * 32];
// TODO: properly calculate this instead of whatever this is
for (int j = 0; j < 32; j++)
for (int i = 0; i < 32; i++)
- data[i + j * 32] = fmin(1.f, 0.1f + 2.f * (distance(vec2(i, j), vec2(16, 16)) / 16));
+ data[i + j * 32] = fmin(1.f, 0.3f + 2.f * (distance(vec2(i, j), vec2(16, 16)) / 16));
glGenTextures(NQ, bbTexIds);
- /* GLuint captureFBO; */
- /* glGenFramebuffers(1, &captureFBO); */
for (int i = 0; i < NQ; i++) {
glBindTexture(GL_TEXTURE_2D, bbTexIds[i]);
- /* glTexImage2D(GL_TEXTURE_2D, 0, GL_R32F, 32, 32, 0, GL_RED, */
- /* GL_FLOAT, data); */
+ checkError();
+
glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, 32, 32, 0, GL_RED, GL_FLOAT, data);
glGenerateMipmap(GL_TEXTURE_2D); // required, otherwise texture is blank
bbColors.clear();
glDisable(GL_DEPTH_TEST);
+ // shaderOutput * 0 + buffer * shader alpha
glBlendFunc(GL_ZERO, GL_SRC_ALPHA);
glEnable(GL_BLEND);
sort(metaballs.begin(), metaballs.end(), [](Metaball &a, Metaball &b) {
return distance(sunPos, a.pos) < distance(sunPos, b.pos);
});
- /* GLuint fbo; */
- /* glGenFramebuffers(1, &fbo); */
- /* glBindFramebuffer(GL_FRAMEBUFFER, fbo); */
- /* glBindTexture(GL_TEXTURE_2D, attenuationTex); */
- /* glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, */
- /* GL_UNSIGNED_BYTE, NULL); */
- /* glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, */
- /* attenuationTex, 0); */
- /* assert(glCheckFramebufferStatus(GL_FRAMEBUFFER) == GL_FRAMEBUFFER_COMPLETE); */
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, bbTexIds[0]);
glUniform1i(glGetUniformLocation(bbProg, "tex"), 0);
-/* glClearColor(1, 1, 1, 1); */
-/* glClear(GL_COLOR_BUFFER_BIT); */
-
-
GLuint modelLoc = glGetUniformLocation(bbProg, "model");
for (auto k : metaballs) {
// Map the billboard texture with GL_MODULATE.
// i.e. multiply rather than add
- // TODO: FIX- this crashes with invalid operation
- /* glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); */
+ // but glTexEnv is for the old fixed function pipeline --
+ // need to just tell our fragment shader then to modulate
+ glUniform1i(glGetUniformLocation(bbProg, "modulate"), 1);
// Render the billboard.
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
pixel *= sunColor;
// Store the color into an array C[k] as the color of the billboard.
- fprintf(stderr, "pixel: ");
- dump(pixel);
bbColors.push_back(pixel);
}
- /* saveFBO(); */
+ saveFBO();
checkError();
-
- /* glDeleteFramebuffers(1, &fbo); */
- /* glBindFramebuffer(GL_FRAMEBUFFER, 0); // render to screen */
}
void renderObject() {}
glDisable(GL_DEPTH_TEST);
glEnable(GL_BLEND);
+ // shaderOutput * 1 + buffer * shader alpha
glBlendFunc(GL_ONE, GL_SRC_ALPHA);
for (int i = 0; i < metaballs.size(); i++) {
Metaball k = metaballs[i];
// Set the billboard color as C[n].
fprintf(stderr, "bbColors[i]: ");
dump(bbColors[i]);
- /* bbColors[i] = {0,0,0,0.5}; */
+ bbColors[i].w = 1;
glUniform4fv(glGetUniformLocation(bbProg, "color"), 1,
glm::value_ptr(bbColors[i]));
glBindTexture(GL_TEXTURE_2D, bbTexIds[0]);
glUniform1i(glGetUniformLocation(bbProg, "tex"), 0);
+ // Don't modulate it -- blend it
+ glUniform1i(glGetUniformLocation(bbProg, "modulate"), 0);
+
// Render the billboard with the blending function.
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
}