/**
* @brief Sorts Decals so that as many decals can be batched together as possible
*
* This uses the bitmaps in the definitions to determine if two decals can be rendered at the same time. Since we use
* texture arrays we can use the base frame for batching which increases the number of draw calls that can be batched together.
*
* @param left
* @param right
* @return
*/
bool decal_draw_list::sort_draws(const decal_draw_info& left, const decal_draw_info& right) {
auto left_diffuse_base = bm_get_base_frame(left.draw_mat.get_texture_map(TM_BASE_TYPE));
auto right_diffuse_base = bm_get_base_frame(right.draw_mat.get_texture_map(TM_BASE_TYPE));
if (left_diffuse_base != right_diffuse_base) {
return left_diffuse_base < right_diffuse_base;
}
auto left_normal_base = bm_get_base_frame(left.draw_mat.get_texture_map(TM_NORMAL_TYPE));
auto right_normal_base = bm_get_base_frame(left.draw_mat.get_texture_map(TM_NORMAL_TYPE));
return left_normal_base < right_normal_base;
}
void decal_draw_list::add_decal(int diffuse_bitmap,
int normal_bitmap,
float decal_timer,
const matrix4& transform,
float base_alpha) {
if (!check_box_in_view(transform)) {
// The decal box is not in view so we don't need to render it
return;
}
auto& aligner = _buffer->aligner();
auto info = aligner.addTypedElement<graphics::decal_info>();
info->model_matrix = transform;
// This is currently a constant but in the future this may be configurable by the decals table
info->normal_angle_cutoff = DECAL_ANGLE_CUTOFF;
info->angle_fade_start = DECAL_ANGLE_FADE_START;
info->alpha_scale = base_alpha;
matrix transform_rot;
vm_matrix4_get_orientation(&transform_rot, &transform);
// The decal shader works in view-space so the direction also has to be transformed into that space
vm_vec_transform(&info->decal_direction, &transform_rot.vec.fvec, &gr_view_matrix, false);
vm_inverse_matrix4(&info->model_matrix, &info->inv_model_matrix);
info->diffuse_index = bm_get_array_index(diffuse_bitmap);
info->normal_index = bm_get_array_index(normal_bitmap);
decal_draw_info current_draw;
current_draw.uniform_offset = aligner.getCurrentOffset();
material_set_decal(¤t_draw.draw_mat, bm_get_base_frame(diffuse_bitmap), bm_get_base_frame(normal_bitmap));
info->blend_mode = current_draw.draw_mat.get_blend_mode() == ALPHA_BLEND_ADDITIVE ? 1 : 0;
_draws.push_back(current_draw);
}
primitive_batch* batching_find_batch(int texture, batch_info::material_type material_id, primitive_type prim_type, bool thruster)
{
// Use the base texture for finding the batch item since all items can reuse the same texture array
auto base_tex = bm_get_base_frame(texture);
batch_info query(material_id, base_tex, prim_type, thruster);
SCP_map<batch_info, primitive_batch>::iterator iter = Batching_primitives.find(query);
if ( iter == Batching_primitives.end() ) {
primitive_batch* batch = &Batching_primitives[query];
*batch = primitive_batch(query);
return batch;
} else {
return &iter->second;
}
}
